1 Guile NEWS --- history of user-visible changes. -*- text -*-
2 Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
3 See the end for copying conditions.
5 Please send Guile bug reports to bug-guile@gnu.org.
7 Changes since Guile 1.4:
9 * Changes to the distribution
11 ** New modules (oop goops) etc
18 (oop goops active-slot)
19 (oop goops composite-slot)
21 plus some GOOPS utility modules have been added.
23 * Changes to the stand-alone interpreter
25 ** GOOPS has been merged into Guile
27 The Guile Object Oriented Programming System has been integrated into
32 (use-modules (oop goops))
34 access GOOPS bindings.
36 We're now ready to try some basic GOOPS functionality.
40 (define-method (+ (x <string>) (y <string>))
44 (+ "abc" "de") --> "abcde"
48 (define-class <2D-vector> ()
49 (x #:init-value 0 #:accessor x-component #:init-keyword #:x)
50 (y #:init-value 0 #:accessor y-component #:init-keyword #:y))
52 (define-method write ((obj <2D-vector>) port)
53 (display (format #f "<~S, ~S>" (x-component obj) (y-component obj))
56 (define v (make <2D-vector> #:x 3 #:y 4))
59 (define-method + ((x <2D-vector>) (y <2D-vector>))
61 #:x (+ (x-component x) (x-component y))
62 #:y (+ (y-component x) (y-component y))))
66 Asking for the type of an object
68 (class-of v) --> #<<class> <2D-vector> 40241ac0>
69 <2D-vector> --> #<<class> <2D-vector> 40241ac0>
70 (class-of 1) --> #<<class> <integer> 401b2a98>
71 <integer> --> #<<class> <integer> 401b2a98>
73 (is-a? v <2D-vector>) --> #t
75 See further in the GOOPS tutorial available in the guile-doc
76 distribution in info (goops.info) and texinfo formats.
78 ** It's now possible to create modules with controlled environments
82 (use-modules (ice-9 safe))
83 (define m (make-safe-module))
84 ;;; m will now be a module containing only a safe subset of R5RS
85 (eval-in-module '(+ 1 2) m) --> 3
86 (eval-in-module 'load m) --> ERROR: Unbound variable: load
88 * Changes to Scheme functions and syntax
90 ** Escape procedures created by call-with-current-continuation now
91 accept any number of arguments, as required by R5RS.
93 ** New function `make-object-property'
95 This function returns a new `procedure with setter' P that can be used
96 to attach a property to objects. When calling P as
100 where `obj' is any kind of object, it attaches `val' to `obj' in such
101 a way that it can be retrieved by calling P as
105 This function will replace procedure properties, symbol properties and
106 source properties eventually.
108 ** Module (ice-9 optargs) now uses keywords instead of `#&'.
110 Instead of #&optional, #&key, etc you should now use #:optional,
111 #:key, etc. Since #:optional is a keyword, you can write it as just
112 :optional when (read-set! keywords 'prefix) is active.
114 The old reader syntax `#&' is still supported, but deprecated. It
115 will be removed in the next release.
117 ** Backward incompatible change: eval EXP ENVIRONMENT-SPECIFIER
119 `eval' is now R5RS, that is it takes two arguments.
120 The second argument is an environment specifier, i.e. either
122 (scheme-report-environment 5)
124 (interaction-environment)
130 ** New define-module option: pure
132 Tells the module system not to include any bindings from the root
137 (define-module (totally-empty-module)
140 ** New define-module option: export NAME1 ...
142 Export names NAME1 ...
144 This option is required if you want to be able to export bindings from
145 a module which doesn't import one of `define-public' or `export'.
151 :use-module (ice-9 r5rs)
154 ;;; Note that we're pure R5RS below this point!
159 ** Deprecated: scm_make_shared_substring
161 Explicit shared substrings will disappear from Guile.
163 Instead, "normal" strings will be implemented using sharing
164 internally, combined with a copy-on-write strategy.
166 ** Deprecated: scm_read_only_string_p
168 The concept of read-only strings will disappear in next release of
171 ** Deprecated: scm_sloppy_memq, scm_sloppy_memv, scm_sloppy_member
173 Instead, use scm_c_memq or scm_memq, scm_memv, scm_member.
175 ** New function: port? X
177 Returns a boolean indicating whether X is a port. Equivalent to
178 `(or (input-port? X) (output-port? X))'.
180 ** New function: port-for-each proc
182 Apply PROC to each port in the Guile port table in turn. The
183 return value is unspecified.
185 ** New function: dup2 oldfd newfd
187 A simple wrapper for the `dup2' system call. Copies the file
188 descriptor OLDFD to descriptor number NEWFD, replacing the
189 previous meaning of NEWFD. Both OLDFD and NEWFD must be integers.
190 Unlike for dup->fdes or primitive-move->fdes, no attempt is made
191 to move away ports which are using NEWFD\n". The return value is
194 ** New function: close-fdes fd
196 A simple wrapper for the `close' system call. Close file
197 descriptor FD, which must be an integer. Unlike close (*note
198 close: Ports and File Descriptors.), the file descriptor will be
199 closed even if a port is using it. The return value is
202 ** Deprecated: close-all-ports-except. This was intended for closing
203 ports in a child process after a fork, but it has the undesirable side
204 effect of flushing buffers. port-for-each is more flexible.
206 ** The (ice-9 popen) module now attempts to set up file descriptors in
207 the child process from the current Scheme ports, instead of using the
208 current values of file descriptors 0, 1, and 2 in the parent process.
210 * Changes to the gh_ interface
212 * Changes to the scm_ interface
214 ** New function: scm_init_guile ()
216 In contrast to scm_boot_guile, scm_init_guile will return normally
217 after initializing Guile. It is not available on all systems, tho.
219 ** New functions: scm_primitive_make_property
220 scm_primitive_property_ref
221 scm_primitive_property_set_x
222 scm_primitive_property_del_x
224 These functions implement a new way to deal with object properties.
225 See libguile/properties.c for their documentation.
227 ** New function: scm_done_free (long size)
229 This function is the inverse of scm_done_malloc. Use it to report the
230 amount of smob memory you free. The previous method, which involved
231 calling scm_done_malloc with negative argument, was somewhat
232 unintuitive (and is still available, of course).
234 ** New function: scm_c_memq (SCM obj, SCM list)
236 This function provides a fast C level alternative for scm_memq for the case
237 that the list parameter is known to be a proper list. The function is a
238 replacement for scm_sloppy_memq, but is stricter in its requirements on its
239 list input parameter, since for anything else but a proper list the function's
240 behaviour is undefined - it may even crash or loop endlessly. Further, for
241 the case that the object is not found in the list, scm_c_memq returns #f which
242 is similar to scm_memq, but different from scm_sloppy_memq's behaviour.
244 ** New global variable scm_gc_running_p introduced.
246 Use this variable to find out if garbage collection is being executed. Up to
247 now applications have used scm_gc_heap_lock to test if garbage collection was
248 running, which also works because of the fact that up to know only the garbage
249 collector has set this variable. But, this is an implementation detail that
250 may change. Further, scm_gc_heap_lock is not set throughout gc, thus the use
251 of this variable is (and has been) not fully safe anyway.
253 ** New macros: SCM_BITVECTOR_MAX_LENGTH, SCM_UVECTOR_MAX_LENGTH
255 Use these instead of SCM_LENGTH_MAX.
257 ** New macros: SCM_CONTINUATION_LENGTH, SCM_CCLO_LENGTH, SCM_STACK_LENGTH,
258 SCM_STRING_LENGTH, SCM_SYMBOL_LENGTH, SCM_UVECTOR_LENGTH,
259 SCM_BITVECTOR_LENGTH, SCM_VECTOR_LENGTH.
261 Use these instead of SCM_LENGTH.
263 ** New macros: SCM_SET_CONTINUATION_LENGTH, SCM_SET_STRING_LENGTH,
264 SCM_SET_SYMBOL_LENGTH, SCM_SET_VECTOR_LENGTH, SCM_SET_UVECTOR_LENGTH,
265 SCM_SET_BITVECTOR_LENGTH
267 Use these instead of SCM_SETLENGTH
269 ** New macros: SCM_STRING_CHARS, SCM_SYMBOL_CHARS, SCM_CCLO_BASE,
270 SCM_VECTOR_BASE, SCM_UVECTOR_BASE, SCM_BITVECTOR_BASE, SCM_COMPLEX_MEM,
273 Use these instead of SCM_CHARS, SCM_UCHARS, SCM_ROCHARS, SCM_ROUCHARS or
276 ** New macros: SCM_SET_BIGNUM_BASE, SCM_SET_STRING_CHARS,
277 SCM_SET_SYMBOL_CHARS, SCM_SET_UVECTOR_BASE, SCM_SET_BITVECTOR_BASE,
280 Use these instead of SCM_SETCHARS.
282 ** New macro: SCM_BITVECTOR_P
284 ** New macro: SCM_STRING_COERCE_0TERMINATION_X
286 Use instead of SCM_COERCE_SUBSTR.
288 ** Deprecated macros: SCM_OUTOFRANGE, SCM_NALLOC, SCM_HUP_SIGNAL,
289 SCM_INT_SIGNAL, SCM_FPE_SIGNAL, SCM_BUS_SIGNAL, SCM_SEGV_SIGNAL,
290 SCM_ALRM_SIGNAL, SCM_GC_SIGNAL, SCM_TICK_SIGNAL, SCM_SIG_ORD,
291 SCM_ORD_SIG, SCM_NUM_SIGS, SCM_SYMBOL_SLOTS, SCM_SLOTS, SCM_SLOPPY_STRINGP,
292 SCM_VALIDATE_STRINGORSUBSTR, SCM_FREEP, SCM_NFREEP, SCM_CHARS, SCM_UCHARS,
293 SCM_VALIDATE_ROSTRING, SCM_VALIDATE_ROSTRING_COPY,
294 SCM_VALIDATE_NULLORROSTRING_COPY, SCM_ROLENGTH, SCM_LENGTH, SCM_HUGE_LENGTH,
295 SCM_SUBSTRP, SCM_SUBSTR_STR, SCM_SUBSTR_OFFSET, SCM_COERCE_SUBSTR,
296 SCM_ROSTRINGP, SCM_RWSTRINGP, SCM_VALIDATE_RWSTRING, SCM_ROCHARS,
297 SCM_ROUCHARS, SCM_SETLENGTH, SCM_SETCHARS, SCM_LENGTH_MAX, SCM_GC8MARKP,
298 SCM_SETGC8MARK, SCM_CLRGC8MARK, SCM_GCTYP16, SCM_GCCDR
300 Use SCM_ASSERT_RANGE or SCM_VALIDATE_XXX_RANGE instead of SCM_OUTOFRANGE.
301 Use scm_memory_error instead of SCM_NALLOC.
302 Use SCM_STRINGP instead of SCM_SLOPPY_STRINGP.
303 Use SCM_VALIDATE_STRING instead of SCM_VALIDATE_STRINGORSUBSTR.
304 Use SCM_FREE_CELL_P instead of SCM_FREEP/SCM_NFREEP
305 Use a type specific accessor macro instead of SCM_CHARS/SCM_UCHARS.
306 Use a type specific accessor instead of SCM(_|_RO|_HUGE_)LENGTH.
307 Use SCM_VALIDATE_(SYMBOL|STRING) instead of SCM_VALIDATE_ROSTRING.
308 Use SCM_STRING_COERCE_0TERMINATION_X instead of SCM_COERCE_SUBSTR.
309 Use SCM_STRINGP or SCM_SYMBOLP instead of SCM_ROSTRINGP.
310 Use SCM_STRINGP instead of SCM_RWSTRINGP.
311 Use SCM_VALIDATE_STRING instead of SCM_VALIDATE_RWSTRING.
312 Use SCM_STRING_CHARS instead of SCM_ROCHARS.
313 Use SCM_STRING_UCHARS instead of SCM_ROUCHARS.
314 Use a type specific setter macro instead of SCM_SETLENGTH.
315 Use a type specific setter macro instead of SCM_SETCHARS.
316 Use a type specific length macro instead of SCM_LENGTH_MAX.
317 Use SCM_GCMARKP instead of SCM_GC8MARKP.
318 Use SCM_SETGCMARK instead of SCM_SETGC8MARK.
319 Use SCM_CLRGCMARK instead of SCM_CLRGC8MARK.
320 Use SCM_TYP16 instead of SCM_GCTYP16.
321 Use SCM_CDR instead of SCM_GCCDR.
323 ** Removed function: scm_struct_init
325 ** Renamed function: scm_make_cont has been replaced by
326 scm_make_continuation, which has a different interface.
328 ** Deprecated function: scm_call_catching_errors
330 Use scm_catch or scm_lazy_catch from throw.[ch] instead.
332 ** Deprecated function: scm_strhash
334 Use scm_string_hash instead.
336 ** Deprecated function: scm_vector_set_length_x
338 Instead, create a fresh vector of the desired size and copy the contents.
340 ** scm_gensym has changed prototype
342 scm_gensym now only takes one argument.
344 ** New function: scm_gentemp (SCM prefix, SCM obarray)
346 The builtin `gentemp' has now become a primitive.
348 ** Deprecated type tags: scm_tc7_ssymbol, scm_tc7_msymbol, scm_tcs_symbols,
351 There is now only a single symbol type scm_tc7_symbol.
352 The tag scm_tc7_lvector was not used anyway.
355 Changes since Guile 1.3.4:
357 * Changes to the distribution
359 ** Trees from nightly snapshots and CVS now require you to run autogen.sh.
361 We've changed the way we handle generated files in the Guile source
362 repository. As a result, the procedure for building trees obtained
363 from the nightly FTP snapshots or via CVS has changed:
364 - You must have appropriate versions of autoconf, automake, and
365 libtool installed on your system. See README for info on how to
366 obtain these programs.
367 - Before configuring the tree, you must first run the script
368 `autogen.sh' at the top of the source tree.
370 The Guile repository used to contain not only source files, written by
371 humans, but also some generated files, like configure scripts and
372 Makefile.in files. Even though the contents of these files could be
373 derived mechanically from other files present, we thought it would
374 make the tree easier to build if we checked them into CVS.
376 However, this approach means that minor differences between
377 developer's installed tools and habits affected the whole team.
378 So we have removed the generated files from the repository, and
379 added the autogen.sh script, which will reconstruct them
383 ** configure now has experimental options to remove support for certain
386 --disable-arrays omit array and uniform array support
387 --disable-posix omit posix interfaces
388 --disable-networking omit networking interfaces
389 --disable-regex omit regular expression interfaces
391 These are likely to become separate modules some day.
393 ** New configure option --enable-debug-freelist
395 This enables a debugging version of SCM_NEWCELL(), and also registers
396 an extra primitive, the setter `gc-set-debug-check-freelist!'.
398 Configure with the --enable-debug-freelist option to enable
399 the gc-set-debug-check-freelist! primitive, and then use:
401 (gc-set-debug-check-freelist! #t) # turn on checking of the freelist
402 (gc-set-debug-check-freelist! #f) # turn off checking
404 Checking of the freelist forces a traversal of the freelist and
405 a garbage collection before each allocation of a cell. This can
406 slow down the interpreter dramatically, so the setter should be used to
407 turn on this extra processing only when necessary.
409 ** New configure option --enable-debug-malloc
411 Include code for debugging of calls to scm_must_malloc/realloc/free.
415 1. objects freed by scm_must_free has been mallocated by scm_must_malloc
416 2. objects reallocated by scm_must_realloc has been allocated by
418 3. reallocated objects are reallocated with the same what string
420 But, most importantly, it records the number of allocated objects of
421 each kind. This is useful when searching for memory leaks.
423 A Guile compiled with this option provides the primitive
424 `malloc-stats' which returns an alist with pairs of kind and the
425 number of objects of that kind.
427 ** All includes are now referenced relative to the root directory
429 Since some users have had problems with mixups between Guile and
430 system headers, we have decided to always refer to Guile headers via
431 their parent directories. This essentially creates a "private name
432 space" for Guile headers. This means that the compiler only is given
433 -I options for the root build and root source directory.
435 ** Header files kw.h and genio.h have been removed.
437 ** The module (ice-9 getopt-gnu-style) has been removed.
439 ** New module (ice-9 documentation)
441 Implements the interface to documentation strings associated with
444 * Changes to the stand-alone interpreter
446 ** New command line option --debug
448 Start Guile with debugging evaluator and backtraces enabled.
450 This is useful when debugging your .guile init file or scripts.
454 Usage: (help NAME) gives documentation about objects named NAME (a symbol)
455 (help REGEXP) ditto for objects with names matching REGEXP (a string)
456 (help ,EXPR) gives documentation for object returned by EXPR
457 (help) gives this text
459 `help' searches among bindings exported from loaded modules, while
460 `apropos' searches among bindings visible from the "current" module.
462 Examples: (help help)
464 (help "output-string")
466 ** `help' and `apropos' now prints full module names
468 ** Dynamic linking now uses libltdl from the libtool package.
470 The old system dependent code for doing dynamic linking has been
471 replaced with calls to the libltdl functions which do all the hairy
474 The major improvement is that you can now directly pass libtool
475 library names like "libfoo.la" to `dynamic-link' and `dynamic-link'
476 will be able to do the best shared library job you can get, via
479 The way dynamic libraries are found has changed and is not really
480 portable across platforms, probably. It is therefore recommended to
481 use absolute filenames when possible.
483 If you pass a filename without an extension to `dynamic-link', it will
484 try a few appropriate ones. Thus, the most platform ignorant way is
485 to specify a name like "libfoo", without any directories and
488 ** Guile COOP threads are now compatible with LinuxThreads
490 Previously, COOP threading wasn't possible in applications linked with
491 Linux POSIX threads due to their use of the stack pointer to find the
492 thread context. This has now been fixed with a workaround which uses
493 the pthreads to allocate the stack.
495 ** New primitives: `pkgdata-dir', `site-dir', `library-dir'
497 ** Positions of erring expression in scripts
499 With version 1.3.4, the location of the erring expression in Guile
500 scipts is no longer automatically reported. (This should have been
501 documented before the 1.3.4 release.)
503 You can get this information by enabling recording of positions of
504 source expressions and running the debugging evaluator. Put this at
505 the top of your script (or in your "site" file):
507 (read-enable 'positions)
508 (debug-enable 'debug)
510 ** Backtraces in scripts
512 It is now possible to get backtraces in scripts.
516 (debug-enable 'debug 'backtrace)
518 at the top of the script.
520 (The first options enables the debugging evaluator.
521 The second enables backtraces.)
523 ** Part of module system symbol lookup now implemented in C
525 The eval closure of most modules is now implemented in C. Since this
526 was one of the bottlenecks for loading speed, Guile now loads code
527 substantially faster than before.
529 ** Attempting to get the value of an unbound variable now produces
530 an exception with a key of 'unbound-variable instead of 'misc-error.
532 ** The initial default output port is now unbuffered if it's using a
533 tty device. Previously in this situation it was line-buffered.
535 ** gc-thunk is deprecated
537 gc-thunk will be removed in next release of Guile. It has been
538 replaced by after-gc-hook.
540 ** New hook: after-gc-hook
542 after-gc-hook takes over the role of gc-thunk. This hook is run at
543 the first SCM_TICK after a GC. (Thus, the code is run at the same
544 point during evaluation as signal handlers.)
546 Note that this hook should be used only for diagnostic and debugging
547 purposes. It is not certain that it will continue to be well-defined
548 when this hook is run in the future.
550 C programmers: Note the new C level hooks scm_before_gc_c_hook,
551 scm_before_sweep_c_hook, scm_after_gc_c_hook.
553 ** Improvements to garbage collector
555 Guile 1.4 has a new policy for triggering heap allocation and
556 determining the sizes of heap segments. It fixes a number of problems
559 1. The new policy can handle two separate pools of cells
560 (2-word/4-word) better. (The old policy would run wild, allocating
561 more and more memory for certain programs.)
563 2. The old code would sometimes allocate far too much heap so that the
564 Guile process became gigantic. The new code avoids this.
566 3. The old code would sometimes allocate too little so that few cells
567 were freed at GC so that, in turn, too much time was spent in GC.
569 4. The old code would often trigger heap allocation several times in a
570 row. (The new scheme predicts how large the segments needs to be
571 in order not to need further allocation.)
573 All in all, the new GC policy will make larger applications more
576 The new GC scheme also is prepared for POSIX threading. Threads can
577 allocate private pools of cells ("clusters") with just a single
578 function call. Allocation of single cells from such a cluster can
579 then proceed without any need of inter-thread synchronization.
581 ** New environment variables controlling GC parameters
583 GUILE_MAX_SEGMENT_SIZE Maximal segment size
586 Allocation of 2-word cell heaps:
588 GUILE_INIT_SEGMENT_SIZE_1 Size of initial heap segment in bytes
591 GUILE_MIN_YIELD_1 Minimum number of freed cells at each
592 GC in percent of total heap size
595 Allocation of 4-word cell heaps
596 (used for real numbers and misc other objects):
598 GUILE_INIT_SEGMENT_SIZE_2, GUILE_MIN_YIELD_2
600 (See entry "Way for application to customize GC parameters" under
601 section "Changes to the scm_ interface" below.)
603 ** Guile now implements reals using 4-word cells
605 This speeds up computation with reals. (They were earlier allocated
606 with `malloc'.) There is still some room for optimizations, however.
608 ** Some further steps toward POSIX thread support have been taken
610 *** Guile's critical sections (SCM_DEFER/ALLOW_INTS)
611 don't have much effect any longer, and many of them will be removed in
615 are only handled at the top of the evaluator loop, immediately after
616 I/O, and in scm_equalp.
618 *** The GC can allocate thread private pools of pairs.
620 * Changes to Scheme functions and syntax
622 ** close-input-port and close-output-port are now R5RS
624 These procedures have been turned into primitives and have R5RS behaviour.
626 ** New procedure: simple-format PORT MESSAGE ARG1 ...
628 (ice-9 boot) makes `format' an alias for `simple-format' until possibly
629 extended by the more sophisticated version in (ice-9 format)
631 (simple-format port message . args)
632 Write MESSAGE to DESTINATION, defaulting to `current-output-port'.
633 MESSAGE can contain ~A (was %s) and ~S (was %S) escapes. When printed,
634 the escapes are replaced with corresponding members of ARGS:
635 ~A formats using `display' and ~S formats using `write'.
636 If DESTINATION is #t, then use the `current-output-port',
637 if DESTINATION is #f, then return a string containing the formatted text.
638 Does not add a trailing newline."
640 ** string-ref: the second argument is no longer optional.
642 ** string, list->string: no longer accept strings in their arguments,
643 only characters, for compatibility with R5RS.
645 ** New procedure: port-closed? PORT
646 Returns #t if PORT is closed or #f if it is open.
650 The list* functionality is now provided by cons* (SRFI-1 compliant)
652 ** New procedure: cons* ARG1 ARG2 ... ARGn
654 Like `list', but the last arg provides the tail of the constructed list,
655 returning (cons ARG1 (cons ARG2 (cons ... ARGn))).
657 Requires at least one argument. If given one argument, that argument
658 is returned as result.
660 This function is called `list*' in some other Schemes and in Common LISP.
662 ** Removed deprecated: serial-map, serial-array-copy!, serial-array-map!
664 ** New procedure: object-documentation OBJECT
666 Returns the documentation string associated with OBJECT. The
667 procedure uses a caching mechanism so that subsequent lookups are
670 Exported by (ice-9 documentation).
672 ** module-name now returns full names of modules
674 Previously, only the last part of the name was returned (`session' for
675 `(ice-9 session)'). Ex: `(ice-9 session)'.
677 * Changes to the gh_ interface
679 ** Deprecated: gh_int2scmb
681 Use gh_bool2scm instead.
683 * Changes to the scm_ interface
685 ** Guile primitives now carry docstrings!
687 Thanks to Greg Badros!
689 ** Guile primitives are defined in a new way: SCM_DEFINE/SCM_DEFINE1/SCM_PROC
691 Now Guile primitives are defined using the SCM_DEFINE/SCM_DEFINE1/SCM_PROC
692 macros and must contain a docstring that is extracted into foo.doc using a new
693 guile-doc-snarf script (that uses guile-doc-snarf.awk).
695 However, a major overhaul of these macros is scheduled for the next release of
698 ** Guile primitives use a new technique for validation of arguments
700 SCM_VALIDATE_* macros are defined to ease the redundancy and improve
701 the readability of argument checking.
703 ** All (nearly?) K&R prototypes for functions replaced with ANSI C equivalents.
705 ** New macros: SCM_PACK, SCM_UNPACK
707 Compose/decompose an SCM value.
709 The SCM type is now treated as an abstract data type and may be defined as a
710 long, a void* or as a struct, depending on the architecture and compile time
711 options. This makes it easier to find several types of bugs, for example when
712 SCM values are treated as integers without conversion. Values of the SCM type
713 should be treated as "atomic" values. These macros are used when
714 composing/decomposing an SCM value, either because you want to access
715 individual bits, or because you want to treat it as an integer value.
717 E.g., in order to set bit 7 in an SCM value x, use the expression
719 SCM_PACK (SCM_UNPACK (x) | 0x80)
721 ** The name property of hooks is deprecated.
722 Thus, the use of SCM_HOOK_NAME and scm_make_hook_with_name is deprecated.
724 You can emulate this feature by using object properties.
726 ** Deprecated macros: SCM_INPORTP, SCM_OUTPORTP, SCM_CRDY, SCM_ICHRP,
727 SCM_ICHR, SCM_MAKICHR, SCM_SETJMPBUF, SCM_NSTRINGP, SCM_NRWSTRINGP,
730 These macros will be removed in a future release of Guile.
732 ** The following types, functions and macros from numbers.h are deprecated:
733 scm_dblproc, SCM_UNEGFIXABLE, SCM_FLOBUFLEN, SCM_INEXP, SCM_CPLXP, SCM_REAL,
734 SCM_IMAG, SCM_REALPART, scm_makdbl, SCM_SINGP, SCM_NUM2DBL, SCM_NO_BIGDIG
736 Further, it is recommended not to rely on implementation details for guile's
737 current implementation of bignums. It is planned to replace this
738 implementation with gmp in the future.
740 ** Port internals: the rw_random variable in the scm_port structure
741 must be set to non-zero in any random access port. In recent Guile
742 releases it was only set for bidirectional random-access ports.
744 ** Port internals: the seek ptob procedure is now responsible for
745 resetting the buffers if required. The change was made so that in the
746 special case of reading the current position (i.e., seek p 0 SEEK_CUR)
747 the fport and strport ptobs can avoid resetting the buffers,
748 in particular to avoid discarding unread chars. An existing port
749 type can be fixed by adding something like the following to the
750 beginning of the ptob seek procedure:
752 if (pt->rw_active == SCM_PORT_READ)
753 scm_end_input (object);
754 else if (pt->rw_active == SCM_PORT_WRITE)
755 ptob->flush (object);
757 although to actually avoid resetting the buffers and discard unread
758 chars requires further hacking that depends on the characteristics
761 ** Deprecated functions: scm_fseek, scm_tag
763 These functions are no longer used and will be removed in a future version.
765 ** The scm_sysmissing procedure is no longer used in libguile.
766 Unless it turns out to be unexpectedly useful to somebody, it will be
767 removed in a future version.
769 ** The format of error message strings has changed
771 The two C procedures: scm_display_error and scm_error, as well as the
772 primitive `scm-error', now use scm_simple_format to do their work.
773 This means that the message strings of all code must be updated to use
774 ~A where %s was used before, and ~S where %S was used before.
776 During the period when there still are a lot of old Guiles out there,
777 you might want to support both old and new versions of Guile.
779 There are basically two methods to achieve this. Both methods use
782 AC_CHECK_FUNCS(scm_simple_format)
784 in your configure.in.
786 Method 1: Use the string concatenation features of ANSI C's
791 #ifdef HAVE_SCM_SIMPLE_FORMAT
797 Then represent each of your error messages using a preprocessor macro:
799 #define E_SPIDER_ERROR "There's a spider in your " ## FMT_S ## "!!!"
803 (define fmt-s (if (defined? 'simple-format) "~S" "%S"))
804 (define make-message string-append)
806 (define e-spider-error (make-message "There's a spider in your " fmt-s "!!!"))
808 Method 2: Use the oldfmt function found in doc/oldfmt.c.
812 scm_misc_error ("picnic", scm_c_oldfmt0 ("There's a spider in your ~S!!!"),
817 (scm-error 'misc-error "picnic" (oldfmt "There's a spider in your ~S!!!")
821 ** Deprecated: coop_mutex_init, coop_condition_variable_init
823 Don't use the functions coop_mutex_init and
824 coop_condition_variable_init. They will change.
826 Use scm_mutex_init and scm_cond_init instead.
828 ** New function: int scm_cond_timedwait (scm_cond_t *COND, scm_mutex_t *MUTEX, const struct timespec *ABSTIME)
829 `scm_cond_timedwait' atomically unlocks MUTEX and waits on
830 COND, as `scm_cond_wait' does, but it also bounds the duration
831 of the wait. If COND has not been signaled before time ABSTIME,
832 the mutex MUTEX is re-acquired and `scm_cond_timedwait'
833 returns the error code `ETIMEDOUT'.
835 The ABSTIME parameter specifies an absolute time, with the same
836 origin as `time' and `gettimeofday': an ABSTIME of 0 corresponds
837 to 00:00:00 GMT, January 1, 1970.
839 ** New function: scm_cond_broadcast (scm_cond_t *COND)
840 `scm_cond_broadcast' restarts all the threads that are waiting
841 on the condition variable COND. Nothing happens if no threads are
844 ** New function: scm_key_create (scm_key_t *KEY, void (*destr_function) (void *))
845 `scm_key_create' allocates a new TSD key. The key is stored in
846 the location pointed to by KEY. There is no limit on the number
847 of keys allocated at a given time. The value initially associated
848 with the returned key is `NULL' in all currently executing threads.
850 The DESTR_FUNCTION argument, if not `NULL', specifies a destructor
851 function associated with the key. When a thread terminates,
852 DESTR_FUNCTION is called on the value associated with the key in
853 that thread. The DESTR_FUNCTION is not called if a key is deleted
854 with `scm_key_delete' or a value is changed with
855 `scm_setspecific'. The order in which destructor functions are
856 called at thread termination time is unspecified.
858 Destructors are not yet implemented.
860 ** New function: scm_setspecific (scm_key_t KEY, const void *POINTER)
861 `scm_setspecific' changes the value associated with KEY in the
862 calling thread, storing the given POINTER instead.
864 ** New function: scm_getspecific (scm_key_t KEY)
865 `scm_getspecific' returns the value currently associated with
866 KEY in the calling thread.
868 ** New function: scm_key_delete (scm_key_t KEY)
869 `scm_key_delete' deallocates a TSD key. It does not check
870 whether non-`NULL' values are associated with that key in the
871 currently executing threads, nor call the destructor function
872 associated with the key.
874 ** New function: scm_c_hook_init (scm_c_hook_t *HOOK, void *HOOK_DATA, scm_c_hook_type_t TYPE)
876 Initialize a C level hook HOOK with associated HOOK_DATA and type
877 TYPE. (See scm_c_hook_run ().)
879 ** New function: scm_c_hook_add (scm_c_hook_t *HOOK, scm_c_hook_function_t FUNC, void *FUNC_DATA, int APPENDP)
881 Add hook function FUNC with associated FUNC_DATA to HOOK. If APPENDP
882 is true, add it last, otherwise first. The same FUNC can be added
883 multiple times if FUNC_DATA differ and vice versa.
885 ** New function: scm_c_hook_remove (scm_c_hook_t *HOOK, scm_c_hook_function_t FUNC, void *FUNC_DATA)
887 Remove hook function FUNC with associated FUNC_DATA from HOOK. A
888 function is only removed if both FUNC and FUNC_DATA matches.
890 ** New function: void *scm_c_hook_run (scm_c_hook_t *HOOK, void *DATA)
892 Run hook HOOK passing DATA to the hook functions.
894 If TYPE is SCM_C_HOOK_NORMAL, all hook functions are run. The value
895 returned is undefined.
897 If TYPE is SCM_C_HOOK_OR, hook functions are run until a function
898 returns a non-NULL value. This value is returned as the result of
899 scm_c_hook_run. If all functions return NULL, NULL is returned.
901 If TYPE is SCM_C_HOOK_AND, hook functions are run until a function
902 returns a NULL value, and NULL is returned. If all functions returns
903 a non-NULL value, the last value is returned.
905 ** New C level GC hooks
907 Five new C level hooks has been added to the garbage collector.
912 are run before locking and after unlocking the heap. The system is
913 thus in a mode where evaluation can take place. (Except that
914 scm_before_gc_c_hook must not allocate new cells.)
916 scm_before_mark_c_hook
917 scm_before_sweep_c_hook
918 scm_after_sweep_c_hook
920 are run when the heap is locked. These are intended for extension of
921 the GC in a modular fashion. Examples are the weaks and guardians
924 ** Way for application to customize GC parameters
926 The application can set up other default values for the GC heap
927 allocation parameters
929 GUILE_INIT_HEAP_SIZE_1, GUILE_MIN_YIELD_1,
930 GUILE_INIT_HEAP_SIZE_2, GUILE_MIN_YIELD_2,
931 GUILE_MAX_SEGMENT_SIZE,
935 scm_default_init_heap_size_1, scm_default_min_yield_1,
936 scm_default_init_heap_size_2, scm_default_min_yield_2,
937 scm_default_max_segment_size
939 respectively before callong scm_boot_guile.
941 (See entry "New environment variables ..." in section
942 "Changes to the stand-alone interpreter" above.)
944 ** scm_protect_object/scm_unprotect_object now nest
946 This means that you can call scm_protect_object multiple times on an
947 object and count on the object being protected until
948 scm_unprotect_object has been call the same number of times.
950 The functions also have better time complexity.
952 Still, it is usually possible to structure the application in a way
953 that you don't need to use these functions. For example, if you use a
954 protected standard Guile list to keep track of live objects rather
955 than some custom data type, objects will die a natural death when they
956 are no longer needed.
958 ** Deprecated type tags: scm_tc16_flo, scm_tc_flo, scm_tc_dblr, scm_tc_dblc
960 Guile does not provide the float representation for inexact real numbers any
961 more. Now, only doubles are used to represent inexact real numbers. Further,
962 the tag names scm_tc_dblr and scm_tc_dblc have been changed to scm_tc16_real
963 and scm_tc16_complex, respectively.
965 ** Removed deprecated type scm_smobfuns
967 ** Removed deprecated function scm_newsmob
969 ** Warning: scm_make_smob_type_mfpe might become deprecated in a future release
971 There is an ongoing discussion among the developers whether to
972 deprecate `scm_make_smob_type_mfpe' or not. Please use the current
973 standard interface (scm_make_smob_type, scm_set_smob_XXX) in new code
974 until this issue has been settled.
976 ** Removed deprecated type tag scm_tc16_kw
978 ** Added type tag scm_tc16_keyword
980 (This was introduced already in release 1.3.4 but was not documented
983 ** gdb_print now prints "*** Guile not initialized ***" until Guile initialized
985 * Changes to system call interfaces:
987 ** The "select" procedure now tests port buffers for the ability to
988 provide input or accept output. Previously only the underlying file
989 descriptors were checked.
991 ** New variable PIPE_BUF: the maximum number of bytes that can be
992 atomically written to a pipe.
994 ** If a facility is not available on the system when Guile is
995 compiled, the corresponding primitive procedure will not be defined.
996 Previously it would have been defined but would throw a system-error
997 exception if called. Exception handlers which catch this case may
998 need minor modification: an error will be thrown with key
999 'unbound-variable instead of 'system-error. Alternatively it's
1000 now possible to use `defined?' to check whether the facility is
1003 ** Procedures which depend on the timezone should now give the correct
1004 result on systems which cache the TZ environment variable, even if TZ
1005 is changed without calling tzset.
1007 * Changes to the networking interfaces:
1009 ** New functions: htons, ntohs, htonl, ntohl: for converting short and
1010 long integers between network and host format. For now, it's not
1011 particularly convenient to do this kind of thing, but consider:
1013 (define write-network-long
1014 (lambda (value port)
1015 (let ((v (make-uniform-vector 1 1 0)))
1016 (uniform-vector-set! v 0 (htonl value))
1017 (uniform-vector-write v port))))
1019 (define read-network-long
1021 (let ((v (make-uniform-vector 1 1 0)))
1022 (uniform-vector-read! v port)
1023 (ntohl (uniform-vector-ref v 0)))))
1025 ** If inet-aton fails, it now throws an error with key 'misc-error
1026 instead of 'system-error, since errno is not relevant.
1028 ** Certain gethostbyname/gethostbyaddr failures now throw errors with
1029 specific keys instead of 'system-error. The latter is inappropriate
1030 since errno will not have been set. The keys are:
1031 'host-not-found, 'try-again, 'no-recovery and 'no-data.
1033 ** sethostent, setnetent, setprotoent, setservent: now take an
1034 optional argument STAYOPEN, which specifies whether the database
1035 remains open after a database entry is accessed randomly (e.g., using
1036 gethostbyname for the hosts database.) The default is #f. Previously
1040 Changes since Guile 1.3.2:
1042 * Changes to the stand-alone interpreter
1046 An initial version of the Guile debugger written by Chris Hanson has
1047 been added. The debugger is still under development but is included
1048 in the distribution anyway since it is already quite useful.
1054 after an error to enter the debugger. Type `help' inside the debugger
1055 for a description of available commands.
1057 If you prefer to have stack frames numbered and printed in
1058 anti-chronological order and prefer up in the stack to be down on the
1059 screen as is the case in gdb, you can put
1061 (debug-enable 'backwards)
1063 in your .guile startup file. (However, this means that Guile can't
1064 use indentation to indicate stack level.)
1066 The debugger is autoloaded into Guile at the first use.
1068 ** Further enhancements to backtraces
1070 There is a new debug option `width' which controls the maximum width
1071 on the screen of printed stack frames. Fancy printing parameters
1072 ("level" and "length" as in Common LISP) are adaptively adjusted for
1073 each stack frame to give maximum information while still fitting
1074 within the bounds. If the stack frame can't be made to fit by
1075 adjusting parameters, it is simply cut off at the end. This is marked
1078 ** Some modules are now only loaded when the repl is started
1080 The modules (ice-9 debug), (ice-9 session), (ice-9 threads) and (ice-9
1081 regex) are now loaded into (guile-user) only if the repl has been
1082 started. The effect is that the startup time for scripts has been
1083 reduced to 30% of what it was previously.
1085 Correctly written scripts load the modules they require at the top of
1086 the file and should not be affected by this change.
1088 ** Hooks are now represented as smobs
1090 * Changes to Scheme functions and syntax
1092 ** Readline support has changed again.
1094 The old (readline-activator) module is gone. Use (ice-9 readline)
1095 instead, which now contains all readline functionality. So the code
1096 to activate readline is now
1098 (use-modules (ice-9 readline))
1101 This should work at any time, including from the guile prompt.
1103 To avoid confusion about the terms of Guile's license, please only
1104 enable readline for your personal use; please don't make it the
1105 default for others. Here is why we make this rather odd-sounding
1108 Guile is normally licensed under a weakened form of the GNU General
1109 Public License, which allows you to link code with Guile without
1110 placing that code under the GPL. This exception is important to some
1113 However, since readline is distributed under the GNU General Public
1114 License, when you link Guile with readline, either statically or
1115 dynamically, you effectively change Guile's license to the strict GPL.
1116 Whenever you link any strictly GPL'd code into Guile, uses of Guile
1117 which are normally permitted become forbidden. This is a rather
1118 non-obvious consequence of the licensing terms.
1120 So, to make sure things remain clear, please let people choose for
1121 themselves whether to link GPL'd libraries like readline with Guile.
1123 ** regexp-substitute/global has changed slightly, but incompatibly.
1125 If you include a function in the item list, the string of the match
1126 object it receives is the same string passed to
1127 regexp-substitute/global, not some suffix of that string.
1128 Correspondingly, the match's positions are relative to the entire
1129 string, not the suffix.
1131 If the regexp can match the empty string, the way matches are chosen
1132 from the string has changed. regexp-substitute/global recognizes the
1133 same set of matches that list-matches does; see below.
1135 ** New function: list-matches REGEXP STRING [FLAGS]
1137 Return a list of match objects, one for every non-overlapping, maximal
1138 match of REGEXP in STRING. The matches appear in left-to-right order.
1139 list-matches only reports matches of the empty string if there are no
1140 other matches which begin on, end at, or include the empty match's
1143 If present, FLAGS is passed as the FLAGS argument to regexp-exec.
1145 ** New function: fold-matches REGEXP STRING INIT PROC [FLAGS]
1147 For each match of REGEXP in STRING, apply PROC to the match object,
1148 and the last value PROC returned, or INIT for the first call. Return
1149 the last value returned by PROC. We apply PROC to the matches as they
1150 appear from left to right.
1152 This function recognizes matches according to the same criteria as
1155 Thus, you could define list-matches like this:
1157 (define (list-matches regexp string . flags)
1158 (reverse! (apply fold-matches regexp string '() cons flags)))
1160 If present, FLAGS is passed as the FLAGS argument to regexp-exec.
1164 *** New function: hook? OBJ
1166 Return #t if OBJ is a hook, otherwise #f.
1168 *** New function: make-hook-with-name NAME [ARITY]
1170 Return a hook with name NAME and arity ARITY. The default value for
1171 ARITY is 0. The only effect of NAME is that it will appear when the
1172 hook object is printed to ease debugging.
1174 *** New function: hook-empty? HOOK
1176 Return #t if HOOK doesn't contain any procedures, otherwise #f.
1178 *** New function: hook->list HOOK
1180 Return a list of the procedures that are called when run-hook is
1183 ** `map' signals an error if its argument lists are not all the same length.
1185 This is the behavior required by R5RS, so this change is really a bug
1186 fix. But it seems to affect a lot of people's code, so we're
1187 mentioning it here anyway.
1189 ** Print-state handling has been made more transparent
1191 Under certain circumstances, ports are represented as a port with an
1192 associated print state. Earlier, this pair was represented as a pair
1193 (see "Some magic has been added to the printer" below). It is now
1194 indistinguishable (almost; see `get-print-state') from a port on the
1197 *** New function: port-with-print-state OUTPUT-PORT PRINT-STATE
1199 Return a new port with the associated print state PRINT-STATE.
1201 *** New function: get-print-state OUTPUT-PORT
1203 Return the print state associated with this port if it exists,
1204 otherwise return #f.
1206 *** New function: directory-stream? OBJECT
1208 Returns true iff OBJECT is a directory stream --- the sort of object
1209 returned by `opendir'.
1211 ** New function: using-readline?
1213 Return #t if readline is in use in the current repl.
1215 ** structs will be removed in 1.4
1217 Structs will be replaced in Guile 1.4. We will merge GOOPS into Guile
1218 and use GOOPS objects as the fundamental record type.
1220 * Changes to the scm_ interface
1222 ** structs will be removed in 1.4
1224 The entire current struct interface (struct.c, struct.h) will be
1225 replaced in Guile 1.4. We will merge GOOPS into libguile and use
1226 GOOPS objects as the fundamental record type.
1228 ** The internal representation of subr's has changed
1230 Instead of giving a hint to the subr name, the CAR field of the subr
1231 now contains an index to a subr entry in scm_subr_table.
1233 *** New variable: scm_subr_table
1235 An array of subr entries. A subr entry contains the name, properties
1236 and documentation associated with the subr. The properties and
1237 documentation slots are not yet used.
1239 ** A new scheme for "forwarding" calls to a builtin to a generic function
1241 It is now possible to extend the functionality of some Guile
1242 primitives by letting them defer a call to a GOOPS generic function on
1243 argument mismatch. This means that there is no loss of efficiency in
1248 (use-modules (oop goops)) ; Must be GOOPS version 0.2.
1249 (define-method + ((x <string>) (y <string>))
1250 (string-append x y))
1252 + will still be as efficient as usual in numerical calculations, but
1253 can also be used for concatenating strings.
1255 Who will be the first one to extend Guile's numerical tower to
1256 rationals? :) [OK, there a few other things to fix before this can
1257 be made in a clean way.]
1259 *** New snarf macros for defining primitives: SCM_GPROC, SCM_GPROC1
1261 New macro: SCM_GPROC (CNAME, SNAME, REQ, OPT, VAR, CFUNC, GENERIC)
1263 New macro: SCM_GPROC1 (CNAME, SNAME, TYPE, CFUNC, GENERIC)
1265 These do the same job as SCM_PROC and SCM_PROC1, but they also define
1266 a variable GENERIC which can be used by the dispatch macros below.
1268 [This is experimental code which may change soon.]
1270 *** New macros for forwarding control to a generic on arg type error
1272 New macro: SCM_WTA_DISPATCH_1 (GENERIC, ARG1, POS, SUBR)
1274 New macro: SCM_WTA_DISPATCH_2 (GENERIC, ARG1, ARG2, POS, SUBR)
1276 These correspond to the scm_wta function call, and have the same
1277 behaviour until the user has called the GOOPS primitive
1278 `enable-primitive-generic!'. After that, these macros will apply the
1279 generic function GENERIC to the argument(s) instead of calling
1282 [This is experimental code which may change soon.]
1284 *** New macros for argument testing with generic dispatch
1286 New macro: SCM_GASSERT1 (COND, GENERIC, ARG1, POS, SUBR)
1288 New macro: SCM_GASSERT2 (COND, GENERIC, ARG1, ARG2, POS, SUBR)
1290 These correspond to the SCM_ASSERT macro, but will defer control to
1291 GENERIC on error after `enable-primitive-generic!' has been called.
1293 [This is experimental code which may change soon.]
1295 ** New function: SCM scm_eval_body (SCM body, SCM env)
1297 Evaluates the body of a special form.
1299 ** The internal representation of struct's has changed
1301 Previously, four slots were allocated for the procedure(s) of entities
1302 and operators. The motivation for this representation had to do with
1303 the structure of the evaluator, the wish to support tail-recursive
1304 generic functions, and efficiency. Since the generic function
1305 dispatch mechanism has changed, there is no longer a need for such an
1306 expensive representation, and the representation has been simplified.
1308 This should not make any difference for most users.
1310 ** GOOPS support has been cleaned up.
1312 Some code has been moved from eval.c to objects.c and code in both of
1313 these compilation units has been cleaned up and better structured.
1315 *** New functions for applying generic functions
1317 New function: SCM scm_apply_generic (GENERIC, ARGS)
1318 New function: SCM scm_call_generic_0 (GENERIC)
1319 New function: SCM scm_call_generic_1 (GENERIC, ARG1)
1320 New function: SCM scm_call_generic_2 (GENERIC, ARG1, ARG2)
1321 New function: SCM scm_call_generic_3 (GENERIC, ARG1, ARG2, ARG3)
1323 ** Deprecated function: scm_make_named_hook
1325 It is now replaced by:
1327 ** New function: SCM scm_create_hook (const char *name, int arity)
1329 Creates a hook in the same way as make-hook above but also
1330 binds a variable named NAME to it.
1332 This is the typical way of creating a hook from C code.
1334 Currently, the variable is created in the "current" module.
1335 This might change when we get the new module system.
1337 [The behaviour is identical to scm_make_named_hook.]
1341 Changes since Guile 1.3:
1343 * Changes to mailing lists
1345 ** Some of the Guile mailing lists have moved to sourceware.cygnus.com.
1347 See the README file to find current addresses for all the Guile
1350 * Changes to the distribution
1352 ** Readline support is no longer included with Guile by default.
1354 Based on the different license terms of Guile and Readline, we
1355 concluded that Guile should not *by default* cause the linking of
1356 Readline into an application program. Readline support is now offered
1357 as a separate module, which is linked into an application only when
1358 you explicitly specify it.
1360 Although Guile is GNU software, its distribution terms add a special
1361 exception to the usual GNU General Public License (GPL). Guile's
1362 license includes a clause that allows you to link Guile with non-free
1363 programs. We add this exception so as not to put Guile at a
1364 disadvantage vis-a-vis other extensibility packages that support other
1367 In contrast, the GNU Readline library is distributed under the GNU
1368 General Public License pure and simple. This means that you may not
1369 link Readline, even dynamically, into an application unless it is
1370 distributed under a free software license that is compatible the GPL.
1372 Because of this difference in distribution terms, an application that
1373 can use Guile may not be able to use Readline. Now users will be
1374 explicitly offered two independent decisions about the use of these
1377 You can activate the readline support by issuing
1379 (use-modules (readline-activator))
1382 from your ".guile" file, for example.
1384 * Changes to the stand-alone interpreter
1386 ** All builtins now print as primitives.
1387 Previously builtin procedures not belonging to the fundamental subr
1388 types printed as #<compiled closure #<primitive-procedure gsubr-apply>>.
1389 Now, they print as #<primitive-procedure NAME>.
1391 ** Backtraces slightly more intelligible.
1392 gsubr-apply and macro transformer application frames no longer appear
1395 * Changes to Scheme functions and syntax
1397 ** Guile now correctly handles internal defines by rewriting them into
1398 their equivalent letrec. Previously, internal defines would
1399 incrementally add to the innermost environment, without checking
1400 whether the restrictions specified in RnRS were met. This lead to the
1401 correct behaviour when these restriction actually were met, but didn't
1402 catch all illegal uses. Such an illegal use could lead to crashes of
1403 the Guile interpreter or or other unwanted results. An example of
1404 incorrect internal defines that made Guile behave erratically:
1416 The problem with this example is that the definition of `c' uses the
1417 value of `b' directly. This confuses the meoization machine of Guile
1418 so that the second call of `b' (this time in a larger environment that
1419 also contains bindings for `c' and `d') refers to the binding of `c'
1420 instead of `a'. You could also make Guile crash with a variation on
1425 (define (b flag) (if flag a 1))
1426 (define c (1+ (b flag)))
1434 From now on, Guile will issue an `Unbound variable: b' error message
1439 A hook contains a list of functions which should be called on
1440 particular occasions in an existing program. Hooks are used for
1443 A window manager might have a hook before-window-map-hook. The window
1444 manager uses the function run-hooks to call all functions stored in
1445 before-window-map-hook each time a window is mapped. The user can
1446 store functions in the hook using add-hook!.
1448 In Guile, hooks are first class objects.
1450 *** New function: make-hook [N_ARGS]
1452 Return a hook for hook functions which can take N_ARGS arguments.
1453 The default value for N_ARGS is 0.
1455 (See also scm_make_named_hook below.)
1457 *** New function: add-hook! HOOK PROC [APPEND_P]
1459 Put PROC at the beginning of the list of functions stored in HOOK.
1460 If APPEND_P is supplied, and non-false, put PROC at the end instead.
1462 PROC must be able to take the number of arguments specified when the
1465 If PROC already exists in HOOK, then remove it first.
1467 *** New function: remove-hook! HOOK PROC
1469 Remove PROC from the list of functions in HOOK.
1471 *** New function: reset-hook! HOOK
1473 Clear the list of hook functions stored in HOOK.
1475 *** New function: run-hook HOOK ARG1 ...
1477 Run all hook functions stored in HOOK with arguments ARG1 ... .
1478 The number of arguments supplied must correspond to the number given
1479 when the hook was created.
1481 ** The function `dynamic-link' now takes optional keyword arguments.
1482 The only keyword argument that is currently defined is `:global
1483 BOOL'. With it, you can control whether the shared library will be
1484 linked in global mode or not. In global mode, the symbols from the
1485 linked library can be used to resolve references from other
1486 dynamically linked libraries. In non-global mode, the linked
1487 library is essentially invisible and can only be accessed via
1488 `dynamic-func', etc. The default is now to link in global mode.
1489 Previously, the default has been non-global mode.
1491 The `#:global' keyword is only effective on platforms that support
1492 the dlopen family of functions.
1494 ** New function `provided?'
1496 - Function: provided? FEATURE
1497 Return true iff FEATURE is supported by this installation of
1498 Guile. FEATURE must be a symbol naming a feature; the global
1499 variable `*features*' is a list of available features.
1501 ** Changes to the module (ice-9 expect):
1503 *** The expect-strings macro now matches `$' in a regular expression
1504 only at a line-break or end-of-file by default. Previously it would
1505 match the end of the string accumulated so far. The old behaviour
1506 can be obtained by setting the variable `expect-strings-exec-flags'
1509 *** The expect-strings macro now uses a variable `expect-strings-exec-flags'
1510 for the regexp-exec flags. If `regexp/noteol' is included, then `$'
1511 in a regular expression will still match before a line-break or
1512 end-of-file. The default is `regexp/noteol'.
1514 *** The expect-strings macro now uses a variable
1515 `expect-strings-compile-flags' for the flags to be supplied to
1516 `make-regexp'. The default is `regexp/newline', which was previously
1519 *** The expect macro now supplies two arguments to a match procedure:
1520 the current accumulated string and a flag to indicate whether
1521 end-of-file has been reached. Previously only the string was supplied.
1522 If end-of-file is reached, the match procedure will be called an
1523 additional time with the same accumulated string as the previous call
1524 but with the flag set.
1526 ** New module (ice-9 format), implementing the Common Lisp `format' function.
1528 This code, and the documentation for it that appears here, was
1529 borrowed from SLIB, with minor adaptations for Guile.
1531 - Function: format DESTINATION FORMAT-STRING . ARGUMENTS
1532 An almost complete implementation of Common LISP format description
1533 according to the CL reference book `Common LISP' from Guy L.
1534 Steele, Digital Press. Backward compatible to most of the
1535 available Scheme format implementations.
1537 Returns `#t', `#f' or a string; has side effect of printing
1538 according to FORMAT-STRING. If DESTINATION is `#t', the output is
1539 to the current output port and `#t' is returned. If DESTINATION
1540 is `#f', a formatted string is returned as the result of the call.
1541 NEW: If DESTINATION is a string, DESTINATION is regarded as the
1542 format string; FORMAT-STRING is then the first argument and the
1543 output is returned as a string. If DESTINATION is a number, the
1544 output is to the current error port if available by the
1545 implementation. Otherwise DESTINATION must be an output port and
1548 FORMAT-STRING must be a string. In case of a formatting error
1549 format returns `#f' and prints a message on the current output or
1550 error port. Characters are output as if the string were output by
1551 the `display' function with the exception of those prefixed by a
1552 tilde (~). For a detailed description of the FORMAT-STRING syntax
1553 please consult a Common LISP format reference manual. For a test
1554 suite to verify this format implementation load `formatst.scm'.
1555 Please send bug reports to `lutzeb@cs.tu-berlin.de'.
1557 Note: `format' is not reentrant, i.e. only one `format'-call may
1558 be executed at a time.
1561 *** Format Specification (Format version 3.0)
1563 Please consult a Common LISP format reference manual for a detailed
1564 description of the format string syntax. For a demonstration of the
1565 implemented directives see `formatst.scm'.
1567 This implementation supports directive parameters and modifiers (`:'
1568 and `@' characters). Multiple parameters must be separated by a comma
1569 (`,'). Parameters can be numerical parameters (positive or negative),
1570 character parameters (prefixed by a quote character (`''), variable
1571 parameters (`v'), number of rest arguments parameter (`#'), empty and
1572 default parameters. Directive characters are case independent. The
1573 general form of a directive is:
1575 DIRECTIVE ::= ~{DIRECTIVE-PARAMETER,}[:][@]DIRECTIVE-CHARACTER
1577 DIRECTIVE-PARAMETER ::= [ [-|+]{0-9}+ | 'CHARACTER | v | # ]
1579 *** Implemented CL Format Control Directives
1581 Documentation syntax: Uppercase characters represent the
1582 corresponding control directive characters. Lowercase characters
1583 represent control directive parameter descriptions.
1586 Any (print as `display' does).
1590 `~MINCOL,COLINC,MINPAD,PADCHARA'
1594 S-expression (print as `write' does).
1598 `~MINCOL,COLINC,MINPAD,PADCHARS'
1604 print number sign always.
1607 print comma separated.
1609 `~MINCOL,PADCHAR,COMMACHARD'
1615 print number sign always.
1618 print comma separated.
1620 `~MINCOL,PADCHAR,COMMACHARX'
1626 print number sign always.
1629 print comma separated.
1631 `~MINCOL,PADCHAR,COMMACHARO'
1637 print number sign always.
1640 print comma separated.
1642 `~MINCOL,PADCHAR,COMMACHARB'
1647 `~N,MINCOL,PADCHAR,COMMACHARR'
1651 print a number as a Roman numeral.
1654 print a number as an "old fashioned" Roman numeral.
1657 print a number as an ordinal English number.
1660 print a number as a cardinal English number.
1665 prints `y' and `ies'.
1668 as `~P but jumps 1 argument backward.'
1671 as `~@P but jumps 1 argument backward.'
1676 prints a character as the reader can understand it (i.e. `#\'
1680 prints a character as emacs does (eg. `^C' for ASCII 03).
1683 Fixed-format floating-point (prints a flonum like MMM.NNN).
1684 `~WIDTH,DIGITS,SCALE,OVERFLOWCHAR,PADCHARF'
1686 If the number is positive a plus sign is printed.
1689 Exponential floating-point (prints a flonum like MMM.NNN`E'EE).
1690 `~WIDTH,DIGITS,EXPONENTDIGITS,SCALE,OVERFLOWCHAR,PADCHAR,EXPONENTCHARE'
1692 If the number is positive a plus sign is printed.
1695 General floating-point (prints a flonum either fixed or
1697 `~WIDTH,DIGITS,EXPONENTDIGITS,SCALE,OVERFLOWCHAR,PADCHAR,EXPONENTCHARG'
1699 If the number is positive a plus sign is printed.
1702 Dollars floating-point (prints a flonum in fixed with signs
1704 `~DIGITS,SCALE,WIDTH,PADCHAR$'
1706 If the number is positive a plus sign is printed.
1709 A sign is always printed and appears before the padding.
1712 The sign appears before the padding.
1720 print newline if not at the beginning of the output line.
1722 prints `~&' and then N-1 newlines.
1727 print N page separators.
1737 newline is ignored, white space left.
1740 newline is left, white space ignored.
1745 relative tabulation.
1751 Indirection (expects indirect arguments as a list).
1753 extracts indirect arguments from format arguments.
1756 Case conversion (converts by `string-downcase').
1758 converts by `string-capitalize'.
1761 converts by `string-capitalize-first'.
1764 converts by `string-upcase'.
1767 Argument Jumping (jumps 1 argument forward).
1769 jumps N arguments forward.
1772 jumps 1 argument backward.
1775 jumps N arguments backward.
1778 jumps to the 0th argument.
1781 jumps to the Nth argument (beginning from 0)
1783 `~[STR0~;STR1~;...~;STRN~]'
1784 Conditional Expression (numerical clause conditional).
1786 take argument from N.
1789 true test conditional.
1792 if-else-then conditional.
1798 default clause follows.
1801 Iteration (args come from the next argument (a list)).
1803 at most N iterations.
1806 args from next arg (a list of lists).
1809 args from the rest of arguments.
1812 args from the rest args (lists).
1823 aborts if N <= M <= K
1825 *** Not Implemented CL Format Control Directives
1828 print `#f' as an empty list (see below).
1831 print `#f' as an empty list (see below).
1837 (sorry I don't understand its semantics completely)
1839 *** Extended, Replaced and Additional Control Directives
1841 `~MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHD'
1842 `~MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHX'
1843 `~MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHO'
1844 `~MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHB'
1845 `~N,MINCOL,PADCHAR,COMMACHAR,COMMAWIDTHR'
1846 COMMAWIDTH is the number of characters between two comma
1850 print a R4RS complex number as `~F~@Fi' with passed parameters for
1854 Pretty print formatting of an argument for scheme code lists.
1860 Flushes the output if format DESTINATION is a port.
1863 Print a `#\space' character
1865 print N `#\space' characters.
1868 Print a `#\tab' character
1870 print N `#\tab' characters.
1873 Takes N as an integer representation for a character. No arguments
1874 are consumed. N is converted to a character by `integer->char'. N
1875 must be a positive decimal number.
1878 Print out readproof. Prints out internal objects represented as
1879 `#<...>' as strings `"#<...>"' so that the format output can always
1880 be processed by `read'.
1883 Print out readproof. Prints out internal objects represented as
1884 `#<...>' as strings `"#<...>"' so that the format output can always
1885 be processed by `read'.
1888 Prints information and a copyright notice on the format
1891 prints format version.
1894 may also print number strings, i.e. passing a number as a string
1895 and format it accordingly.
1897 *** Configuration Variables
1899 The format module exports some configuration variables to suit the
1900 systems and users needs. There should be no modification necessary for
1901 the configuration that comes with Guile. Format detects automatically
1902 if the running scheme system implements floating point numbers and
1905 format:symbol-case-conv
1906 Symbols are converted by `symbol->string' so the case type of the
1907 printed symbols is implementation dependent.
1908 `format:symbol-case-conv' is a one arg closure which is either
1909 `#f' (no conversion), `string-upcase', `string-downcase' or
1910 `string-capitalize'. (default `#f')
1912 format:iobj-case-conv
1913 As FORMAT:SYMBOL-CASE-CONV but applies for the representation of
1914 implementation internal objects. (default `#f')
1917 The character prefixing the exponent value in `~E' printing.
1920 *** Compatibility With Other Format Implementations
1926 Downward compatible except for padding support and `~A', `~S',
1927 `~P', `~X' uppercase printing. SLIB format 1.4 uses C-style
1928 `printf' padding support which is completely replaced by the CL
1929 `format' padding style.
1932 Downward compatible except for `~', which is not documented
1933 (ignores all characters inside the format string up to a newline
1934 character). (7.1 implements `~a', `~s', ~NEWLINE, `~~', `~%',
1935 numerical and variable parameters and `:/@' modifiers in the CL
1939 Downward compatible except for `~A' and `~S' which print in
1940 uppercase. (Elk implements `~a', `~s', `~~', and `~%' (no
1941 directive parameters or modifiers)).
1944 Downward compatible except for an optional destination parameter:
1945 S2C accepts a format call without a destination which returns a
1946 formatted string. This is equivalent to a #f destination in S2C.
1947 (S2C implements `~a', `~s', `~c', `~%', and `~~' (no directive
1948 parameters or modifiers)).
1951 ** Changes to string-handling functions.
1953 These functions were added to support the (ice-9 format) module, above.
1955 *** New function: string-upcase STRING
1956 *** New function: string-downcase STRING
1958 These are non-destructive versions of the existing string-upcase! and
1959 string-downcase! functions.
1961 *** New function: string-capitalize! STRING
1962 *** New function: string-capitalize STRING
1964 These functions convert the first letter of each word in the string to
1967 (string-capitalize "howdy there")
1970 As with the other functions, string-capitalize! modifies the string in
1971 place, while string-capitalize returns a modified copy of its argument.
1973 *** New function: string-ci->symbol STRING
1975 Return a symbol whose name is STRING, but having the same case as if
1976 the symbol had be read by `read'.
1978 Guile can be configured to be sensitive or insensitive to case
1979 differences in Scheme identifiers. If Guile is case-insensitive, all
1980 symbols are converted to lower case on input. The `string-ci->symbol'
1981 function returns a symbol whose name in STRING, transformed as Guile
1982 would if STRING were input.
1984 *** New function: substring-move! STRING1 START END STRING2 START
1986 Copy the substring of STRING1 from START (inclusive) to END
1987 (exclusive) to STRING2 at START. STRING1 and STRING2 may be the same
1988 string, and the source and destination areas may overlap; in all
1989 cases, the function behaves as if all the characters were copied
1992 *** Extended functions: substring-move-left! substring-move-right!
1994 These functions now correctly copy arbitrarily overlapping substrings;
1995 they are both synonyms for substring-move!.
1998 ** New module (ice-9 getopt-long), with the function `getopt-long'.
2000 getopt-long is a function for parsing command-line arguments in a
2001 manner consistent with other GNU programs.
2003 (getopt-long ARGS GRAMMAR)
2004 Parse the arguments ARGS according to the argument list grammar GRAMMAR.
2006 ARGS should be a list of strings. Its first element should be the
2007 name of the program; subsequent elements should be the arguments
2008 that were passed to the program on the command line. The
2009 `program-arguments' procedure returns a list of this form.
2011 GRAMMAR is a list of the form:
2012 ((OPTION (PROPERTY VALUE) ...) ...)
2014 Each OPTION should be a symbol. `getopt-long' will accept a
2015 command-line option named `--OPTION'.
2016 Each option can have the following (PROPERTY VALUE) pairs:
2018 (single-char CHAR) --- Accept `-CHAR' as a single-character
2019 equivalent to `--OPTION'. This is how to specify traditional
2021 (required? BOOL) --- If BOOL is true, the option is required.
2022 getopt-long will raise an error if it is not found in ARGS.
2023 (value BOOL) --- If BOOL is #t, the option accepts a value; if
2024 it is #f, it does not; and if it is the symbol
2025 `optional', the option may appear in ARGS with or
2027 (predicate FUNC) --- If the option accepts a value (i.e. you
2028 specified `(value #t)' for this option), then getopt
2029 will apply FUNC to the value, and throw an exception
2030 if it returns #f. FUNC should be a procedure which
2031 accepts a string and returns a boolean value; you may
2032 need to use quasiquotes to get it into GRAMMAR.
2034 The (PROPERTY VALUE) pairs may occur in any order, but each
2035 property may occur only once. By default, options do not have
2036 single-character equivalents, are not required, and do not take
2039 In ARGS, single-character options may be combined, in the usual
2040 Unix fashion: ("-x" "-y") is equivalent to ("-xy"). If an option
2041 accepts values, then it must be the last option in the
2042 combination; the value is the next argument. So, for example, using
2043 the following grammar:
2044 ((apples (single-char #\a))
2045 (blimps (single-char #\b) (value #t))
2046 (catalexis (single-char #\c) (value #t)))
2047 the following argument lists would be acceptable:
2048 ("-a" "-b" "bang" "-c" "couth") ("bang" and "couth" are the values
2049 for "blimps" and "catalexis")
2050 ("-ab" "bang" "-c" "couth") (same)
2051 ("-ac" "couth" "-b" "bang") (same)
2052 ("-abc" "couth" "bang") (an error, since `-b' is not the
2053 last option in its combination)
2055 If an option's value is optional, then `getopt-long' decides
2056 whether it has a value by looking at what follows it in ARGS. If
2057 the next element is a string, and it does not appear to be an
2058 option itself, then that string is the option's value.
2060 The value of a long option can appear as the next element in ARGS,
2061 or it can follow the option name, separated by an `=' character.
2062 Thus, using the same grammar as above, the following argument lists
2064 ("--apples" "Braeburn" "--blimps" "Goodyear")
2065 ("--apples=Braeburn" "--blimps" "Goodyear")
2066 ("--blimps" "Goodyear" "--apples=Braeburn")
2068 If the option "--" appears in ARGS, argument parsing stops there;
2069 subsequent arguments are returned as ordinary arguments, even if
2070 they resemble options. So, in the argument list:
2071 ("--apples" "Granny Smith" "--" "--blimp" "Goodyear")
2072 `getopt-long' will recognize the `apples' option as having the
2073 value "Granny Smith", but it will not recognize the `blimp'
2074 option; it will return the strings "--blimp" and "Goodyear" as
2075 ordinary argument strings.
2077 The `getopt-long' function returns the parsed argument list as an
2078 assocation list, mapping option names --- the symbols from GRAMMAR
2079 --- onto their values, or #t if the option does not accept a value.
2080 Unused options do not appear in the alist.
2082 All arguments that are not the value of any option are returned
2083 as a list, associated with the empty list.
2085 `getopt-long' throws an exception if:
2086 - it finds an unrecognized option in ARGS
2087 - a required option is omitted
2088 - an option that requires an argument doesn't get one
2089 - an option that doesn't accept an argument does get one (this can
2090 only happen using the long option `--opt=value' syntax)
2091 - an option predicate fails
2096 `((lockfile-dir (required? #t)
2099 (predicate ,file-is-directory?))
2100 (verbose (required? #f)
2103 (x-includes (single-char #\x))
2104 (rnet-server (single-char #\y)
2105 (predicate ,string?))))
2107 (getopt-long '("my-prog" "-vk" "/tmp" "foo1" "--x-includes=/usr/include"
2108 "--rnet-server=lamprod" "--" "-fred" "foo2" "foo3")
2110 => ((() "foo1" "-fred" "foo2" "foo3")
2111 (rnet-server . "lamprod")
2112 (x-includes . "/usr/include")
2113 (lockfile-dir . "/tmp")
2116 ** The (ice-9 getopt-gnu-style) module is obsolete; use (ice-9 getopt-long).
2118 It will be removed in a few releases.
2120 ** New syntax: lambda*
2121 ** New syntax: define*
2122 ** New syntax: define*-public
2123 ** New syntax: defmacro*
2124 ** New syntax: defmacro*-public
2125 Guile now supports optional arguments.
2127 `lambda*', `define*', `define*-public', `defmacro*' and
2128 `defmacro*-public' are identical to the non-* versions except that
2129 they use an extended type of parameter list that has the following BNF
2130 syntax (parentheses are literal, square brackets indicate grouping,
2131 and `*', `+' and `?' have the usual meaning):
2133 ext-param-list ::= ( [identifier]* [#&optional [ext-var-decl]+]?
2134 [#&key [ext-var-decl]+ [#&allow-other-keys]?]?
2135 [[#&rest identifier]|[. identifier]]? ) | [identifier]
2137 ext-var-decl ::= identifier | ( identifier expression )
2139 The semantics are best illustrated with the following documentation
2140 and examples for `lambda*':
2143 lambda extended for optional and keyword arguments
2145 lambda* creates a procedure that takes optional arguments. These
2146 are specified by putting them inside brackets at the end of the
2147 paramater list, but before any dotted rest argument. For example,
2148 (lambda* (a b #&optional c d . e) '())
2149 creates a procedure with fixed arguments a and b, optional arguments c
2150 and d, and rest argument e. If the optional arguments are omitted
2151 in a call, the variables for them are unbound in the procedure. This
2152 can be checked with the bound? macro.
2154 lambda* can also take keyword arguments. For example, a procedure
2156 (lambda* (#&key xyzzy larch) '())
2157 can be called with any of the argument lists (#:xyzzy 11)
2158 (#:larch 13) (#:larch 42 #:xyzzy 19) (). Whichever arguments
2159 are given as keywords are bound to values.
2161 Optional and keyword arguments can also be given default values
2162 which they take on when they are not present in a call, by giving a
2163 two-item list in place of an optional argument, for example in:
2164 (lambda* (foo #&optional (bar 42) #&key (baz 73)) (list foo bar baz))
2165 foo is a fixed argument, bar is an optional argument with default
2166 value 42, and baz is a keyword argument with default value 73.
2167 Default value expressions are not evaluated unless they are needed
2168 and until the procedure is called.
2170 lambda* now supports two more special parameter list keywords.
2172 lambda*-defined procedures now throw an error by default if a
2173 keyword other than one of those specified is found in the actual
2174 passed arguments. However, specifying #&allow-other-keys
2175 immediately after the kyword argument declarations restores the
2176 previous behavior of ignoring unknown keywords. lambda* also now
2177 guarantees that if the same keyword is passed more than once, the
2178 last one passed is the one that takes effect. For example,
2179 ((lambda* (#&key (heads 0) (tails 0)) (display (list heads tails)))
2180 #:heads 37 #:tails 42 #:heads 99)
2181 would result in (99 47) being displayed.
2183 #&rest is also now provided as a synonym for the dotted syntax rest
2184 argument. The argument lists (a . b) and (a #&rest b) are equivalent in
2185 all respects to lambda*. This is provided for more similarity to DSSSL,
2186 MIT-Scheme and Kawa among others, as well as for refugees from other
2189 Further documentation may be found in the optargs.scm file itself.
2191 The optional argument module also exports the macros `let-optional',
2192 `let-optional*', `let-keywords', `let-keywords*' and `bound?'. These
2193 are not documented here because they may be removed in the future, but
2194 full documentation is still available in optargs.scm.
2196 ** New syntax: and-let*
2197 Guile now supports the `and-let*' form, described in the draft SRFI-2.
2199 Syntax: (land* (<clause> ...) <body> ...)
2200 Each <clause> should have one of the following forms:
2201 (<variable> <expression>)
2204 Each <variable> or <bound-variable> should be an identifier. Each
2205 <expression> should be a valid expression. The <body> should be a
2206 possibly empty sequence of expressions, like the <body> of a
2209 Semantics: A LAND* expression is evaluated by evaluating the
2210 <expression> or <bound-variable> of each of the <clause>s from
2211 left to right. The value of the first <expression> or
2212 <bound-variable> that evaluates to a false value is returned; the
2213 remaining <expression>s and <bound-variable>s are not evaluated.
2214 The <body> forms are evaluated iff all the <expression>s and
2215 <bound-variable>s evaluate to true values.
2217 The <expression>s and the <body> are evaluated in an environment
2218 binding each <variable> of the preceding (<variable> <expression>)
2219 clauses to the value of the <expression>. Later bindings
2220 shadow earlier bindings.
2222 Guile's and-let* macro was contributed by Michael Livshin.
2224 ** New sorting functions
2226 *** New function: sorted? SEQUENCE LESS?
2227 Returns `#t' when the sequence argument is in non-decreasing order
2228 according to LESS? (that is, there is no adjacent pair `... x y
2229 ...' for which `(less? y x)').
2231 Returns `#f' when the sequence contains at least one out-of-order
2232 pair. It is an error if the sequence is neither a list nor a
2235 *** New function: merge LIST1 LIST2 LESS?
2236 LIST1 and LIST2 are sorted lists.
2237 Returns the sorted list of all elements in LIST1 and LIST2.
2239 Assume that the elements a and b1 in LIST1 and b2 in LIST2 are "equal"
2240 in the sense that (LESS? x y) --> #f for x, y in {a, b1, b2},
2241 and that a < b1 in LIST1. Then a < b1 < b2 in the result.
2242 (Here "<" should read "comes before".)
2244 *** New procedure: merge! LIST1 LIST2 LESS?
2245 Merges two lists, re-using the pairs of LIST1 and LIST2 to build
2246 the result. If the code is compiled, and LESS? constructs no new
2247 pairs, no pairs at all will be allocated. The first pair of the
2248 result will be either the first pair of LIST1 or the first pair of
2251 *** New function: sort SEQUENCE LESS?
2252 Accepts either a list or a vector, and returns a new sequence
2253 which is sorted. The new sequence is the same type as the input.
2254 Always `(sorted? (sort sequence less?) less?)'. The original
2255 sequence is not altered in any way. The new sequence shares its
2256 elements with the old one; no elements are copied.
2258 *** New procedure: sort! SEQUENCE LESS
2259 Returns its sorted result in the original boxes. No new storage is
2260 allocated at all. Proper usage: (set! slist (sort! slist <))
2262 *** New function: stable-sort SEQUENCE LESS?
2263 Similar to `sort' but stable. That is, if "equal" elements are
2264 ordered a < b in the original sequence, they will have the same order
2267 *** New function: stable-sort! SEQUENCE LESS?
2268 Similar to `sort!' but stable.
2269 Uses temporary storage when sorting vectors.
2271 *** New functions: sort-list, sort-list!
2272 Added for compatibility with scsh.
2274 ** New built-in random number support
2276 *** New function: random N [STATE]
2277 Accepts a positive integer or real N and returns a number of the
2278 same type between zero (inclusive) and N (exclusive). The values
2279 returned have a uniform distribution.
2281 The optional argument STATE must be of the type produced by
2282 `copy-random-state' or `seed->random-state'. It defaults to the value
2283 of the variable `*random-state*'. This object is used to maintain the
2284 state of the pseudo-random-number generator and is altered as a side
2285 effect of the `random' operation.
2287 *** New variable: *random-state*
2288 Holds a data structure that encodes the internal state of the
2289 random-number generator that `random' uses by default. The nature
2290 of this data structure is implementation-dependent. It may be
2291 printed out and successfully read back in, but may or may not
2292 function correctly as a random-number state object in another
2295 *** New function: copy-random-state [STATE]
2296 Returns a new object of type suitable for use as the value of the
2297 variable `*random-state*' and as a second argument to `random'.
2298 If argument STATE is given, a copy of it is returned. Otherwise a
2299 copy of `*random-state*' is returned.
2301 *** New function: seed->random-state SEED
2302 Returns a new object of type suitable for use as the value of the
2303 variable `*random-state*' and as a second argument to `random'.
2304 SEED is a string or a number. A new state is generated and
2305 initialized using SEED.
2307 *** New function: random:uniform [STATE]
2308 Returns an uniformly distributed inexact real random number in the
2309 range between 0 and 1.
2311 *** New procedure: random:solid-sphere! VECT [STATE]
2312 Fills VECT with inexact real random numbers the sum of whose
2313 squares is less than 1.0. Thinking of VECT as coordinates in
2314 space of dimension N = `(vector-length VECT)', the coordinates are
2315 uniformly distributed within the unit N-shere. The sum of the
2316 squares of the numbers is returned. VECT can be either a vector
2317 or a uniform vector of doubles.
2319 *** New procedure: random:hollow-sphere! VECT [STATE]
2320 Fills VECT with inexact real random numbers the sum of whose squares
2321 is equal to 1.0. Thinking of VECT as coordinates in space of
2322 dimension n = `(vector-length VECT)', the coordinates are uniformly
2323 distributed over the surface of the unit n-shere. VECT can be either
2324 a vector or a uniform vector of doubles.
2326 *** New function: random:normal [STATE]
2327 Returns an inexact real in a normal distribution with mean 0 and
2328 standard deviation 1. For a normal distribution with mean M and
2329 standard deviation D use `(+ M (* D (random:normal)))'.
2331 *** New procedure: random:normal-vector! VECT [STATE]
2332 Fills VECT with inexact real random numbers which are independent and
2333 standard normally distributed (i.e., with mean 0 and variance 1).
2334 VECT can be either a vector or a uniform vector of doubles.
2336 *** New function: random:exp STATE
2337 Returns an inexact real in an exponential distribution with mean 1.
2338 For an exponential distribution with mean U use (* U (random:exp)).
2340 ** The range of logand, logior, logxor, logtest, and logbit? have changed.
2342 These functions now operate on numbers in the range of a C unsigned
2345 These functions used to operate on numbers in the range of a C signed
2346 long; however, this seems inappropriate, because Guile integers don't
2349 ** New function: make-guardian
2350 This is an implementation of guardians as described in
2351 R. Kent Dybvig, Carl Bruggeman, and David Eby (1993) "Guardians in a
2352 Generation-Based Garbage Collector" ACM SIGPLAN Conference on
2353 Programming Language Design and Implementation, June 1993
2354 ftp://ftp.cs.indiana.edu/pub/scheme-repository/doc/pubs/guardians.ps.gz
2356 ** New functions: delq1!, delv1!, delete1!
2357 These procedures behave similar to delq! and friends but delete only
2358 one object if at all.
2360 ** New function: unread-string STRING PORT
2361 Unread STRING to PORT, that is, push it back onto the port so that
2362 next read operation will work on the pushed back characters.
2364 ** unread-char can now be called multiple times
2365 If unread-char is called multiple times, the unread characters will be
2366 read again in last-in first-out order.
2368 ** the procedures uniform-array-read! and uniform-array-write! now
2369 work on any kind of port, not just ports which are open on a file.
2371 ** Now 'l' in a port mode requests line buffering.
2373 ** The procedure truncate-file now works on string ports as well
2374 as file ports. If the size argument is omitted, the current
2375 file position is used.
2377 ** new procedure: seek PORT/FDES OFFSET WHENCE
2378 The arguments are the same as for the old fseek procedure, but it
2379 works on string ports as well as random-access file ports.
2381 ** the fseek procedure now works on string ports, since it has been
2382 redefined using seek.
2384 ** the setvbuf procedure now uses a default size if mode is _IOFBF and
2385 size is not supplied.
2387 ** the newline procedure no longer flushes the port if it's not
2388 line-buffered: previously it did if it was the current output port.
2390 ** open-pipe and close-pipe are no longer primitive procedures, but
2391 an emulation can be obtained using `(use-modules (ice-9 popen))'.
2393 ** the freopen procedure has been removed.
2395 ** new procedure: drain-input PORT
2396 Drains PORT's read buffers (including any pushed-back characters)
2397 and returns the contents as a single string.
2399 ** New function: map-in-order PROC LIST1 LIST2 ...
2400 Version of `map' which guarantees that the procedure is applied to the
2401 lists in serial order.
2403 ** Renamed `serial-array-copy!' and `serial-array-map!' to
2404 `array-copy-in-order!' and `array-map-in-order!'. The old names are
2405 now obsolete and will go away in release 1.5.
2407 ** New syntax: collect BODY1 ...
2408 Version of `begin' which returns a list of the results of the body
2409 forms instead of the result of the last body form. In contrast to
2410 `begin', `collect' allows an empty body.
2412 ** New functions: read-history FILENAME, write-history FILENAME
2413 Read/write command line history from/to file. Returns #t on success
2414 and #f if an error occured.
2416 ** `ls' and `lls' in module (ice-9 ls) now handle no arguments.
2418 These procedures return a list of definitions available in the specified
2419 argument, a relative module reference. In the case of no argument,
2420 `(current-module)' is now consulted for definitions to return, instead
2421 of simply returning #f, the former behavior.
2423 ** The #/ syntax for lists is no longer supported.
2425 Earlier versions of Scheme accepted this syntax, but printed a
2428 ** Guile no longer consults the SCHEME_LOAD_PATH environment variable.
2430 Instead, you should set GUILE_LOAD_PATH to tell Guile where to find
2433 * Changes to the gh_ interface
2437 Now takes a second argument which is the result array. If this
2438 pointer is NULL, a new array is malloced (the old behaviour).
2440 ** gh_chars2byvect, gh_shorts2svect, gh_floats2fvect, gh_scm2chars,
2441 gh_scm2shorts, gh_scm2longs, gh_scm2floats
2445 * Changes to the scm_ interface
2447 ** Function: scm_make_named_hook (char* name, int n_args)
2449 Creates a hook in the same way as make-hook above but also
2450 binds a variable named NAME to it.
2452 This is the typical way of creating a hook from C code.
2454 Currently, the variable is created in the "current" module. This
2455 might change when we get the new module system.
2457 ** The smob interface
2459 The interface for creating smobs has changed. For documentation, see
2460 data-rep.info (made from guile-core/doc/data-rep.texi).
2462 *** Deprecated function: SCM scm_newsmob (scm_smobfuns *)
2464 >>> This function will be removed in 1.3.4. <<<
2468 *** Function: SCM scm_make_smob_type (const char *name, scm_sizet size)
2469 This function adds a new smob type, named NAME, with instance size
2470 SIZE to the system. The return value is a tag that is used in
2471 creating instances of the type. If SIZE is 0, then no memory will
2472 be allocated when instances of the smob are created, and nothing
2473 will be freed by the default free function.
2475 *** Function: void scm_set_smob_mark (long tc, SCM (*mark) (SCM))
2476 This function sets the smob marking procedure for the smob type
2477 specified by the tag TC. TC is the tag returned by
2478 `scm_make_smob_type'.
2480 *** Function: void scm_set_smob_free (long tc, SCM (*mark) (SCM))
2481 This function sets the smob freeing procedure for the smob type
2482 specified by the tag TC. TC is the tag returned by
2483 `scm_make_smob_type'.
2485 *** Function: void scm_set_smob_print (tc, print)
2487 - Function: void scm_set_smob_print (long tc,
2488 scm_sizet (*print) (SCM,
2492 This function sets the smob printing procedure for the smob type
2493 specified by the tag TC. TC is the tag returned by
2494 `scm_make_smob_type'.
2496 *** Function: void scm_set_smob_equalp (long tc, SCM (*equalp) (SCM, SCM))
2497 This function sets the smob equality-testing predicate for the
2498 smob type specified by the tag TC. TC is the tag returned by
2499 `scm_make_smob_type'.
2501 *** Macro: void SCM_NEWSMOB (SCM var, long tc, void *data)
2502 Make VALUE contain a smob instance of the type with type code TC and
2503 smob data DATA. VALUE must be previously declared as C type `SCM'.
2505 *** Macro: fn_returns SCM_RETURN_NEWSMOB (long tc, void *data)
2506 This macro expands to a block of code that creates a smob instance
2507 of the type with type code TC and smob data DATA, and returns that
2508 `SCM' value. It should be the last piece of code in a block.
2510 ** The interfaces for using I/O ports and implementing port types
2511 (ptobs) have changed significantly. The new interface is based on
2512 shared access to buffers and a new set of ptob procedures.
2514 *** scm_newptob has been removed
2518 *** Function: SCM scm_make_port_type (type_name, fill_buffer, write_flush)
2520 - Function: SCM scm_make_port_type (char *type_name,
2521 int (*fill_buffer) (SCM port),
2522 void (*write_flush) (SCM port));
2524 Similarly to the new smob interface, there is a set of function
2525 setters by which the user can customize the behaviour of his port
2526 type. See ports.h (scm_set_port_XXX).
2528 ** scm_strport_to_string: New function: creates a new string from
2529 a string port's buffer.
2531 ** Plug in interface for random number generators
2532 The variable `scm_the_rng' in random.c contains a value and three
2533 function pointers which together define the current random number
2534 generator being used by the Scheme level interface and the random
2535 number library functions.
2537 The user is free to replace the default generator with the generator
2540 *** Variable: size_t scm_the_rng.rstate_size
2541 The size of the random state type used by the current RNG
2544 *** Function: unsigned long scm_the_rng.random_bits (scm_rstate *STATE)
2545 Given the random STATE, return 32 random bits.
2547 *** Function: void scm_the_rng.init_rstate (scm_rstate *STATE, chars *S, int N)
2548 Seed random state STATE using string S of length N.
2550 *** Function: scm_rstate *scm_the_rng.copy_rstate (scm_rstate *STATE)
2551 Given random state STATE, return a malloced copy.
2554 The default RNG is the MWC (Multiply With Carry) random number
2555 generator described by George Marsaglia at the Department of
2556 Statistics and Supercomputer Computations Research Institute, The
2557 Florida State University (http://stat.fsu.edu/~geo).
2559 It uses 64 bits, has a period of 4578426017172946943 (4.6e18), and
2560 passes all tests in the DIEHARD test suite
2561 (http://stat.fsu.edu/~geo/diehard.html). The generation of 32 bits
2562 costs one multiply and one add on platforms which either supports long
2563 longs (gcc does this on most systems) or have 64 bit longs. The cost
2564 is four multiply on other systems but this can be optimized by writing
2565 scm_i_uniform32 in assembler.
2567 These functions are provided through the scm_the_rng interface for use
2568 by libguile and the application.
2570 *** Function: unsigned long scm_i_uniform32 (scm_i_rstate *STATE)
2571 Given the random STATE, return 32 random bits.
2572 Don't use this function directly. Instead go through the plugin
2573 interface (see "Plug in interface" above).
2575 *** Function: void scm_i_init_rstate (scm_i_rstate *STATE, char *SEED, int N)
2576 Initialize STATE using SEED of length N.
2578 *** Function: scm_i_rstate *scm_i_copy_rstate (scm_i_rstate *STATE)
2579 Return a malloc:ed copy of STATE. This function can easily be re-used
2580 in the interfaces to other RNGs.
2582 ** Random number library functions
2583 These functions use the current RNG through the scm_the_rng interface.
2584 It might be a good idea to use these functions from your C code so
2585 that only one random generator is used by all code in your program.
2587 The default random state is stored in:
2589 *** Variable: SCM scm_var_random_state
2590 Contains the vcell of the Scheme variable "*random-state*" which is
2591 used as default state by all random number functions in the Scheme
2596 double x = scm_c_uniform01 (SCM_RSTATE (SCM_CDR (scm_var_random_state)));
2598 *** Function: scm_rstate *scm_c_default_rstate (void)
2599 This is a convenience function which returns the value of
2600 scm_var_random_state. An error message is generated if this value
2601 isn't a random state.
2603 *** Function: scm_rstate *scm_c_make_rstate (char *SEED, int LENGTH)
2604 Make a new random state from the string SEED of length LENGTH.
2606 It is generally not a good idea to use multiple random states in a
2607 program. While subsequent random numbers generated from one random
2608 state are guaranteed to be reasonably independent, there is no such
2609 guarantee for numbers generated from different random states.
2611 *** Macro: unsigned long scm_c_uniform32 (scm_rstate *STATE)
2612 Return 32 random bits.
2614 *** Function: double scm_c_uniform01 (scm_rstate *STATE)
2615 Return a sample from the uniform(0,1) distribution.
2617 *** Function: double scm_c_normal01 (scm_rstate *STATE)
2618 Return a sample from the normal(0,1) distribution.
2620 *** Function: double scm_c_exp1 (scm_rstate *STATE)
2621 Return a sample from the exp(1) distribution.
2623 *** Function: unsigned long scm_c_random (scm_rstate *STATE, unsigned long M)
2624 Return a sample from the discrete uniform(0,M) distribution.
2626 *** Function: SCM scm_c_random_bignum (scm_rstate *STATE, SCM M)
2627 Return a sample from the discrete uniform(0,M) distribution.
2628 M must be a bignum object. The returned value may be an INUM.
2632 Changes in Guile 1.3 (released Monday, October 19, 1998):
2634 * Changes to the distribution
2636 ** We renamed the SCHEME_LOAD_PATH environment variable to GUILE_LOAD_PATH.
2637 To avoid conflicts, programs should name environment variables after
2638 themselves, except when there's a common practice establishing some
2641 For now, Guile supports both GUILE_LOAD_PATH and SCHEME_LOAD_PATH,
2642 giving the former precedence, and printing a warning message if the
2643 latter is set. Guile 1.4 will not recognize SCHEME_LOAD_PATH at all.
2645 ** The header files related to multi-byte characters have been removed.
2646 They were: libguile/extchrs.h and libguile/mbstrings.h. Any C code
2647 which referred to these explicitly will probably need to be rewritten,
2648 since the support for the variant string types has been removed; see
2651 ** The header files append.h and sequences.h have been removed. These
2652 files implemented non-R4RS operations which would encourage
2653 non-portable programming style and less easy-to-read code.
2655 * Changes to the stand-alone interpreter
2657 ** New procedures have been added to implement a "batch mode":
2659 *** Function: batch-mode?
2661 Returns a boolean indicating whether the interpreter is in batch
2664 *** Function: set-batch-mode?! ARG
2666 If ARG is true, switches the interpreter to batch mode. The `#f'
2667 case has not been implemented.
2669 ** Guile now provides full command-line editing, when run interactively.
2670 To use this feature, you must have the readline library installed.
2671 The Guile build process will notice it, and automatically include
2674 The readline library is available via anonymous FTP from any GNU
2675 mirror site; the canonical location is "ftp://prep.ai.mit.edu/pub/gnu".
2677 ** the-last-stack is now a fluid.
2679 * Changes to the procedure for linking libguile with your programs
2681 ** You can now use the `guile-config' utility to build programs that use Guile.
2683 Guile now includes a command-line utility called `guile-config', which
2684 can provide information about how to compile and link programs that
2687 *** `guile-config compile' prints any C compiler flags needed to use Guile.
2688 You should include this command's output on the command line you use
2689 to compile C or C++ code that #includes the Guile header files. It's
2690 usually just a `-I' flag to help the compiler find the Guile headers.
2693 *** `guile-config link' prints any linker flags necessary to link with Guile.
2695 This command writes to its standard output a list of flags which you
2696 must pass to the linker to link your code against the Guile library.
2697 The flags include '-lguile' itself, any other libraries the Guile
2698 library depends upon, and any `-L' flags needed to help the linker
2699 find those libraries.
2701 For example, here is a Makefile rule that builds a program named 'foo'
2702 from the object files ${FOO_OBJECTS}, and links them against Guile:
2705 ${CC} ${CFLAGS} ${FOO_OBJECTS} `guile-config link` -o foo
2707 Previous Guile releases recommended that you use autoconf to detect
2708 which of a predefined set of libraries were present on your system.
2709 It is more robust to use `guile-config', since it records exactly which
2710 libraries the installed Guile library requires.
2712 This was originally called `build-guile', but was renamed to
2713 `guile-config' before Guile 1.3 was released, to be consistent with
2714 the analogous script for the GTK+ GUI toolkit, which is called
2718 ** Use the GUILE_FLAGS macro in your configure.in file to find Guile.
2720 If you are using the GNU autoconf package to configure your program,
2721 you can use the GUILE_FLAGS autoconf macro to call `guile-config'
2722 (described above) and gather the necessary values for use in your
2725 The GUILE_FLAGS macro expands to configure script code which runs the
2726 `guile-config' script, to find out where Guile's header files and
2727 libraries are installed. It sets two variables, marked for
2728 substitution, as by AC_SUBST.
2730 GUILE_CFLAGS --- flags to pass to a C or C++ compiler to build
2731 code that uses Guile header files. This is almost always just a
2734 GUILE_LDFLAGS --- flags to pass to the linker to link a
2735 program against Guile. This includes `-lguile' for the Guile
2736 library itself, any libraries that Guile itself requires (like
2737 -lqthreads), and so on. It may also include a -L flag to tell the
2738 compiler where to find the libraries.
2740 GUILE_FLAGS is defined in the file guile.m4, in the top-level
2741 directory of the Guile distribution. You can copy it into your
2742 package's aclocal.m4 file, and then use it in your configure.in file.
2744 If you are using the `aclocal' program, distributed with GNU automake,
2745 to maintain your aclocal.m4 file, the Guile installation process
2746 installs guile.m4 where aclocal will find it. All you need to do is
2747 use GUILE_FLAGS in your configure.in file, and then run `aclocal';
2748 this will copy the definition of GUILE_FLAGS into your aclocal.m4
2752 * Changes to Scheme functions and syntax
2754 ** Multi-byte strings have been removed, as have multi-byte and wide
2755 ports. We felt that these were the wrong approach to
2756 internationalization support.
2758 ** New function: readline [PROMPT]
2759 Read a line from the terminal, and allow the user to edit it,
2760 prompting with PROMPT. READLINE provides a large set of Emacs-like
2761 editing commands, lets the user recall previously typed lines, and
2762 works on almost every kind of terminal, including dumb terminals.
2764 READLINE assumes that the cursor is at the beginning of the line when
2765 it is invoked. Thus, you can't print a prompt yourself, and then call
2766 READLINE; you need to package up your prompt as a string, pass it to
2767 the function, and let READLINE print the prompt itself. This is
2768 because READLINE needs to know the prompt's screen width.
2770 For Guile to provide this function, you must have the readline
2771 library, version 2.1 or later, installed on your system. Readline is
2772 available via anonymous FTP from prep.ai.mit.edu in pub/gnu, or from
2773 any GNU mirror site.
2775 See also ADD-HISTORY function.
2777 ** New function: add-history STRING
2778 Add STRING as the most recent line in the history used by the READLINE
2779 command. READLINE does not add lines to the history itself; you must
2780 call ADD-HISTORY to make previous input available to the user.
2782 ** The behavior of the read-line function has changed.
2784 This function now uses standard C library functions to read the line,
2785 for speed. This means that it doesn not respect the value of
2786 scm-line-incrementors; it assumes that lines are delimited with
2789 (Note that this is read-line, the function that reads a line of text
2790 from a port, not readline, the function that reads a line from a
2791 terminal, providing full editing capabilities.)
2793 ** New module (ice-9 getopt-gnu-style): Parse command-line arguments.
2795 This module provides some simple argument parsing. It exports one
2798 Function: getopt-gnu-style ARG-LS
2799 Parse a list of program arguments into an alist of option
2802 Each item in the list of program arguments is examined to see if
2803 it meets the syntax of a GNU long-named option. An argument like
2804 `--MUMBLE' produces an element of the form (MUMBLE . #t) in the
2805 returned alist, where MUMBLE is a keyword object with the same
2806 name as the argument. An argument like `--MUMBLE=FROB' produces
2807 an element of the form (MUMBLE . FROB), where FROB is a string.
2809 As a special case, the returned alist also contains a pair whose
2810 car is the symbol `rest'. The cdr of this pair is a list
2811 containing all the items in the argument list that are not options
2812 of the form mentioned above.
2814 The argument `--' is treated specially: all items in the argument
2815 list appearing after such an argument are not examined, and are
2816 returned in the special `rest' list.
2818 This function does not parse normal single-character switches.
2819 You will need to parse them out of the `rest' list yourself.
2821 ** The read syntax for byte vectors and short vectors has changed.
2823 Instead of #bytes(...), write #y(...).
2825 Instead of #short(...), write #h(...).
2827 This may seem nutty, but, like the other uniform vectors, byte vectors
2828 and short vectors want to have the same print and read syntax (and,
2829 more basic, want to have read syntax!). Changing the read syntax to
2830 use multiple characters after the hash sign breaks with the
2831 conventions used in R5RS and the conventions used for the other
2832 uniform vectors. It also introduces complexity in the current reader,
2833 both on the C and Scheme levels. (The Right solution is probably to
2834 change the syntax and prototypes for uniform vectors entirely.)
2837 ** The new module (ice-9 session) provides useful interactive functions.
2839 *** New procedure: (apropos REGEXP OPTION ...)
2841 Display a list of top-level variables whose names match REGEXP, and
2842 the modules they are imported from. Each OPTION should be one of the
2845 value --- Show the value of each matching variable.
2846 shadow --- Show bindings shadowed by subsequently imported modules.
2847 full --- Same as both `shadow' and `value'.
2851 guile> (apropos "trace" 'full)
2852 debug: trace #<procedure trace args>
2853 debug: untrace #<procedure untrace args>
2854 the-scm-module: display-backtrace #<compiled-closure #<primitive-procedure gsubr-apply>>
2855 the-scm-module: before-backtrace-hook ()
2856 the-scm-module: backtrace #<primitive-procedure backtrace>
2857 the-scm-module: after-backtrace-hook ()
2858 the-scm-module: has-shown-backtrace-hint? #f
2861 ** There are new functions and syntax for working with macros.
2863 Guile implements macros as a special object type. Any variable whose
2864 top-level binding is a macro object acts as a macro. The macro object
2865 specifies how the expression should be transformed before evaluation.
2867 *** Macro objects now print in a reasonable way, resembling procedures.
2869 *** New function: (macro? OBJ)
2870 True iff OBJ is a macro object.
2872 *** New function: (primitive-macro? OBJ)
2873 Like (macro? OBJ), but true only if OBJ is one of the Guile primitive
2874 macro transformers, implemented in eval.c rather than Scheme code.
2876 Why do we have this function?
2877 - For symmetry with procedure? and primitive-procedure?,
2878 - to allow custom print procedures to tell whether a macro is
2879 primitive, and display it differently, and
2880 - to allow compilers and user-written evaluators to distinguish
2881 builtin special forms from user-defined ones, which could be
2884 *** New function: (macro-type OBJ)
2885 Return a value indicating what kind of macro OBJ is. Possible return
2888 The symbol `syntax' --- a macro created by procedure->syntax.
2889 The symbol `macro' --- a macro created by procedure->macro.
2890 The symbol `macro!' --- a macro created by procedure->memoizing-macro.
2891 The boolean #f --- if OBJ is not a macro object.
2893 *** New function: (macro-name MACRO)
2894 Return the name of the macro object MACRO's procedure, as returned by
2897 *** New function: (macro-transformer MACRO)
2898 Return the transformer procedure for MACRO.
2900 *** New syntax: (use-syntax MODULE ... TRANSFORMER)
2902 Specify a new macro expander to use in the current module. Each
2903 MODULE is a module name, with the same meaning as in the `use-modules'
2904 form; each named module's exported bindings are added to the current
2905 top-level environment. TRANSFORMER is an expression evaluated in the
2906 resulting environment which must yield a procedure to use as the
2907 module's eval transformer: every expression evaluated in this module
2908 is passed to this function, and the result passed to the Guile
2911 *** macro-eval! is removed. Use local-eval instead.
2913 ** Some magic has been added to the printer to better handle user
2914 written printing routines (like record printers, closure printers).
2916 The problem is that these user written routines must have access to
2917 the current `print-state' to be able to handle fancy things like
2918 detection of circular references. These print-states have to be
2919 passed to the builtin printing routines (display, write, etc) to
2920 properly continue the print chain.
2922 We didn't want to change all existing print code so that it
2923 explicitly passes thru a print state in addition to a port. Instead,
2924 we extented the possible values that the builtin printing routines
2925 accept as a `port'. In addition to a normal port, they now also take
2926 a pair of a normal port and a print-state. Printing will go to the
2927 port and the print-state will be used to control the detection of
2928 circular references, etc. If the builtin function does not care for a
2929 print-state, it is simply ignored.
2931 User written callbacks are now called with such a pair as their
2932 `port', but because every function now accepts this pair as a PORT
2933 argument, you don't have to worry about that. In fact, it is probably
2934 safest to not check for these pairs.
2936 However, it is sometimes necessary to continue a print chain on a
2937 different port, for example to get a intermediate string
2938 representation of the printed value, mangle that string somehow, and
2939 then to finally print the mangled string. Use the new function
2941 inherit-print-state OLD-PORT NEW-PORT
2943 for this. It constructs a new `port' that prints to NEW-PORT but
2944 inherits the print-state of OLD-PORT.
2946 ** struct-vtable-offset renamed to vtable-offset-user
2948 ** New constants: vtable-index-layout, vtable-index-vtable, vtable-index-printer
2950 ** There is now a third optional argument to make-vtable-vtable
2951 (and fourth to make-struct) when constructing new types (vtables).
2952 This argument initializes field vtable-index-printer of the vtable.
2954 ** The detection of circular references has been extended to structs.
2955 That is, a structure that -- in the process of being printed -- prints
2956 itself does not lead to infinite recursion.
2958 ** There is now some basic support for fluids. Please read
2959 "libguile/fluid.h" to find out more. It is accessible from Scheme with
2960 the following functions and macros:
2962 Function: make-fluid
2964 Create a new fluid object. Fluids are not special variables or
2965 some other extension to the semantics of Scheme, but rather
2966 ordinary Scheme objects. You can store them into variables (that
2967 are still lexically scoped, of course) or into any other place you
2968 like. Every fluid has a initial value of `#f'.
2970 Function: fluid? OBJ
2972 Test whether OBJ is a fluid.
2974 Function: fluid-ref FLUID
2975 Function: fluid-set! FLUID VAL
2977 Access/modify the fluid FLUID. Modifications are only visible
2978 within the current dynamic root (that includes threads).
2980 Function: with-fluids* FLUIDS VALUES THUNK
2982 FLUIDS is a list of fluids and VALUES a corresponding list of
2983 values for these fluids. Before THUNK gets called the values are
2984 installed in the fluids and the old values of the fluids are
2985 saved in the VALUES list. When the flow of control leaves THUNK
2986 or reenters it, the values get swapped again. You might think of
2987 this as a `safe-fluid-excursion'. Note that the VALUES list is
2988 modified by `with-fluids*'.
2990 Macro: with-fluids ((FLUID VALUE) ...) FORM ...
2992 The same as `with-fluids*' but with a different syntax. It looks
2993 just like `let', but both FLUID and VALUE are evaluated. Remember,
2994 fluids are not special variables but ordinary objects. FLUID
2995 should evaluate to a fluid.
2997 ** Changes to system call interfaces:
2999 *** close-port, close-input-port and close-output-port now return a
3000 boolean instead of an `unspecified' object. #t means that the port
3001 was successfully closed, while #f means it was already closed. It is
3002 also now possible for these procedures to raise an exception if an
3003 error occurs (some errors from write can be delayed until close.)
3005 *** the first argument to chmod, fcntl, ftell and fseek can now be a
3008 *** the third argument to fcntl is now optional.
3010 *** the first argument to chown can now be a file descriptor or a port.
3012 *** the argument to stat can now be a port.
3014 *** The following new procedures have been added (most use scsh
3017 *** procedure: close PORT/FD
3018 Similar to close-port (*note close-port: Closing Ports.), but also
3019 works on file descriptors. A side effect of closing a file
3020 descriptor is that any ports using that file descriptor are moved
3021 to a different file descriptor and have their revealed counts set
3024 *** procedure: port->fdes PORT
3025 Returns the integer file descriptor underlying PORT. As a side
3026 effect the revealed count of PORT is incremented.
3028 *** procedure: fdes->ports FDES
3029 Returns a list of existing ports which have FDES as an underlying
3030 file descriptor, without changing their revealed counts.
3032 *** procedure: fdes->inport FDES
3033 Returns an existing input port which has FDES as its underlying
3034 file descriptor, if one exists, and increments its revealed count.
3035 Otherwise, returns a new input port with a revealed count of 1.
3037 *** procedure: fdes->outport FDES
3038 Returns an existing output port which has FDES as its underlying
3039 file descriptor, if one exists, and increments its revealed count.
3040 Otherwise, returns a new output port with a revealed count of 1.
3042 The next group of procedures perform a `dup2' system call, if NEWFD
3043 (an integer) is supplied, otherwise a `dup'. The file descriptor to be
3044 duplicated can be supplied as an integer or contained in a port. The
3045 type of value returned varies depending on which procedure is used.
3047 All procedures also have the side effect when performing `dup2' that
3048 any ports using NEWFD are moved to a different file descriptor and have
3049 their revealed counts set to zero.
3051 *** procedure: dup->fdes PORT/FD [NEWFD]
3052 Returns an integer file descriptor.
3054 *** procedure: dup->inport PORT/FD [NEWFD]
3055 Returns a new input port using the new file descriptor.
3057 *** procedure: dup->outport PORT/FD [NEWFD]
3058 Returns a new output port using the new file descriptor.
3060 *** procedure: dup PORT/FD [NEWFD]
3061 Returns a new port if PORT/FD is a port, with the same mode as the
3062 supplied port, otherwise returns an integer file descriptor.
3064 *** procedure: dup->port PORT/FD MODE [NEWFD]
3065 Returns a new port using the new file descriptor. MODE supplies a
3066 mode string for the port (*note open-file: File Ports.).
3068 *** procedure: setenv NAME VALUE
3069 Modifies the environment of the current process, which is also the
3070 default environment inherited by child processes.
3072 If VALUE is `#f', then NAME is removed from the environment.
3073 Otherwise, the string NAME=VALUE is added to the environment,
3074 replacing any existing string with name matching NAME.
3076 The return value is unspecified.
3078 *** procedure: truncate-file OBJ SIZE
3079 Truncates the file referred to by OBJ to at most SIZE bytes. OBJ
3080 can be a string containing a file name or an integer file
3081 descriptor or port open for output on the file. The underlying
3082 system calls are `truncate' and `ftruncate'.
3084 The return value is unspecified.
3086 *** procedure: setvbuf PORT MODE [SIZE]
3087 Set the buffering mode for PORT. MODE can be:
3095 block buffered, using a newly allocated buffer of SIZE bytes.
3096 However if SIZE is zero or unspecified, the port will be made
3099 This procedure should not be used after I/O has been performed with
3102 Ports are usually block buffered by default, with a default buffer
3103 size. Procedures e.g., *Note open-file: File Ports, which accept a
3104 mode string allow `0' to be added to request an unbuffered port.
3106 *** procedure: fsync PORT/FD
3107 Copies any unwritten data for the specified output file descriptor
3108 to disk. If PORT/FD is a port, its buffer is flushed before the
3109 underlying file descriptor is fsync'd. The return value is
3112 *** procedure: open-fdes PATH FLAGS [MODES]
3113 Similar to `open' but returns a file descriptor instead of a port.
3115 *** procedure: execle PATH ENV [ARG] ...
3116 Similar to `execl', but the environment of the new process is
3117 specified by ENV, which must be a list of strings as returned by
3118 the `environ' procedure.
3120 This procedure is currently implemented using the `execve' system
3121 call, but we call it `execle' because of its Scheme calling
3124 *** procedure: strerror ERRNO
3125 Returns the Unix error message corresponding to ERRNO, an integer.
3127 *** procedure: primitive-exit [STATUS]
3128 Terminate the current process without unwinding the Scheme stack.
3129 This is would typically be useful after a fork. The exit status
3130 is STATUS if supplied, otherwise zero.
3132 *** procedure: times
3133 Returns an object with information about real and processor time.
3134 The following procedures accept such an object as an argument and
3135 return a selected component:
3138 The current real time, expressed as time units relative to an
3142 The CPU time units used by the calling process.
3145 The CPU time units used by the system on behalf of the
3149 The CPU time units used by terminated child processes of the
3150 calling process, whose status has been collected (e.g., using
3154 Similarly, the CPU times units used by the system on behalf of
3155 terminated child processes.
3157 ** Removed: list-length
3158 ** Removed: list-append, list-append!
3159 ** Removed: list-reverse, list-reverse!
3161 ** array-map renamed to array-map!
3163 ** serial-array-map renamed to serial-array-map!
3165 ** catch doesn't take #f as first argument any longer
3167 Previously, it was possible to pass #f instead of a key to `catch'.
3168 That would cause `catch' to pass a jump buffer object to the procedure
3169 passed as second argument. The procedure could then use this jump
3170 buffer objekt as an argument to throw.
3172 This mechanism has been removed since its utility doesn't motivate the
3173 extra complexity it introduces.
3175 ** The `#/' notation for lists now provokes a warning message from Guile.
3176 This syntax will be removed from Guile in the near future.
3178 To disable the warning message, set the GUILE_HUSH environment
3179 variable to any non-empty value.
3181 ** The newline character now prints as `#\newline', following the
3182 normal Scheme notation, not `#\nl'.
3184 * Changes to the gh_ interface
3186 ** The gh_enter function now takes care of loading the Guile startup files.
3187 gh_enter works by calling scm_boot_guile; see the remarks below.
3189 ** Function: void gh_write (SCM x)
3191 Write the printed representation of the scheme object x to the current
3192 output port. Corresponds to the scheme level `write'.
3194 ** gh_list_length renamed to gh_length.
3196 ** vector handling routines
3198 Several major changes. In particular, gh_vector() now resembles
3199 (vector ...) (with a caveat -- see manual), and gh_make_vector() now
3200 exists and behaves like (make-vector ...). gh_vset() and gh_vref()
3201 have been renamed gh_vector_set_x() and gh_vector_ref(). Some missing
3202 vector-related gh_ functions have been implemented.
3204 ** pair and list routines
3206 Implemented several of the R4RS pair and list functions that were
3209 ** gh_scm2doubles, gh_doubles2scm, gh_doubles2dvect
3211 New function. Converts double arrays back and forth between Scheme
3214 * Changes to the scm_ interface
3216 ** The function scm_boot_guile now takes care of loading the startup files.
3218 Guile's primary initialization function, scm_boot_guile, now takes
3219 care of loading `boot-9.scm', in the `ice-9' module, to initialize
3220 Guile, define the module system, and put together some standard
3221 bindings. It also loads `init.scm', which is intended to hold
3222 site-specific initialization code.
3224 Since Guile cannot operate properly until boot-9.scm is loaded, there
3225 is no reason to separate loading boot-9.scm from Guile's other
3226 initialization processes.
3228 This job used to be done by scm_compile_shell_switches, which didn't
3229 make much sense; in particular, it meant that people using Guile for
3230 non-shell-like applications had to jump through hoops to get Guile
3231 initialized properly.
3233 ** The function scm_compile_shell_switches no longer loads the startup files.
3234 Now, Guile always loads the startup files, whenever it is initialized;
3235 see the notes above for scm_boot_guile and scm_load_startup_files.
3237 ** Function: scm_load_startup_files
3238 This new function takes care of loading Guile's initialization file
3239 (`boot-9.scm'), and the site initialization file, `init.scm'. Since
3240 this is always called by the Guile initialization process, it's
3241 probably not too useful to call this yourself, but it's there anyway.
3243 ** The semantics of smob marking have changed slightly.
3245 The smob marking function (the `mark' member of the scm_smobfuns
3246 structure) is no longer responsible for setting the mark bit on the
3247 smob. The generic smob handling code in the garbage collector will
3248 set this bit. The mark function need only ensure that any other
3249 objects the smob refers to get marked.
3251 Note that this change means that the smob's GC8MARK bit is typically
3252 already set upon entry to the mark function. Thus, marking functions
3253 which look like this:
3256 if (SCM_GC8MARKP (ptr))
3258 SCM_SETGC8MARK (ptr);
3259 ... mark objects to which the smob refers ...
3262 are now incorrect, since they will return early, and fail to mark any
3263 other objects the smob refers to. Some code in the Guile library used
3266 ** The semantics of the I/O port functions in scm_ptobfuns have changed.
3268 If you have implemented your own I/O port type, by writing the
3269 functions required by the scm_ptobfuns and then calling scm_newptob,
3270 you will need to change your functions slightly.
3272 The functions in a scm_ptobfuns structure now expect the port itself
3273 as their argument; they used to expect the `stream' member of the
3274 port's scm_port_table structure. This allows functions in an
3275 scm_ptobfuns structure to easily access the port's cell (and any flags
3276 it its CAR), and the port's scm_port_table structure.
3278 Guile now passes the I/O port itself as the `port' argument in the
3279 following scm_ptobfuns functions:
3281 int (*free) (SCM port);
3282 int (*fputc) (int, SCM port);
3283 int (*fputs) (char *, SCM port);
3284 scm_sizet (*fwrite) SCM_P ((char *ptr,
3288 int (*fflush) (SCM port);
3289 int (*fgetc) (SCM port);
3290 int (*fclose) (SCM port);
3292 The interfaces to the `mark', `print', `equalp', and `fgets' methods
3295 If you have existing code which defines its own port types, it is easy
3296 to convert your code to the new interface; simply apply SCM_STREAM to
3297 the port argument to yield the value you code used to expect.
3299 Note that since both the port and the stream have the same type in the
3300 C code --- they are both SCM values --- the C compiler will not remind
3301 you if you forget to update your scm_ptobfuns functions.
3304 ** Function: int scm_internal_select (int fds,
3308 struct timeval *timeout);
3310 This is a replacement for the `select' function provided by the OS.
3311 It enables I/O blocking and sleeping to happen for one cooperative
3312 thread without blocking other threads. It also avoids busy-loops in
3313 these situations. It is intended that all I/O blocking and sleeping
3314 will finally go through this function. Currently, this function is
3315 only available on systems providing `gettimeofday' and `select'.
3317 ** Function: SCM scm_internal_stack_catch (SCM tag,
3318 scm_catch_body_t body,
3320 scm_catch_handler_t handler,
3323 A new sibling to the other two C level `catch' functions
3324 scm_internal_catch and scm_internal_lazy_catch. Use it if you want
3325 the stack to be saved automatically into the variable `the-last-stack'
3326 (scm_the_last_stack_var) on error. This is necessary if you want to
3327 use advanced error reporting, such as calling scm_display_error and
3328 scm_display_backtrace. (They both take a stack object as argument.)
3330 ** Function: SCM scm_spawn_thread (scm_catch_body_t body,
3332 scm_catch_handler_t handler,
3335 Spawns a new thread. It does a job similar to
3336 scm_call_with_new_thread but takes arguments more suitable when
3337 spawning threads from application C code.
3339 ** The hook scm_error_callback has been removed. It was originally
3340 intended as a way for the user to install his own error handler. But
3341 that method works badly since it intervenes between throw and catch,
3342 thereby changing the semantics of expressions like (catch #t ...).
3343 The correct way to do it is to use one of the C level catch functions
3344 in throw.c: scm_internal_catch/lazy_catch/stack_catch.
3346 ** Removed functions:
3348 scm_obj_length, scm_list_length, scm_list_append, scm_list_append_x,
3349 scm_list_reverse, scm_list_reverse_x
3351 ** New macros: SCM_LISTn where n is one of the integers 0-9.
3353 These can be used for pretty list creation from C. The idea is taken
3354 from Erick Gallesio's STk.
3356 ** scm_array_map renamed to scm_array_map_x
3358 ** mbstrings are now removed
3360 This means that the type codes scm_tc7_mb_string and
3361 scm_tc7_mb_substring has been removed.
3363 ** scm_gen_putc, scm_gen_puts, scm_gen_write, and scm_gen_getc have changed.
3365 Since we no longer support multi-byte strings, these I/O functions
3366 have been simplified, and renamed. Here are their old names, and
3367 their new names and arguments:
3369 scm_gen_putc -> void scm_putc (int c, SCM port);
3370 scm_gen_puts -> void scm_puts (char *s, SCM port);
3371 scm_gen_write -> void scm_lfwrite (char *ptr, scm_sizet size, SCM port);
3372 scm_gen_getc -> void scm_getc (SCM port);
3375 ** The macros SCM_TYP7D and SCM_TYP7SD has been removed.
3377 ** The macro SCM_TYP7S has taken the role of the old SCM_TYP7D
3379 SCM_TYP7S now masks away the bit which distinguishes substrings from
3382 ** scm_catch_body_t: Backward incompatible change!
3384 Body functions to scm_internal_catch and friends do not any longer
3385 take a second argument. This is because it is no longer possible to
3386 pass a #f arg to catch.
3388 ** Calls to scm_protect_object and scm_unprotect now nest properly.
3390 The function scm_protect_object protects its argument from being freed
3391 by the garbage collector. scm_unprotect_object removes that
3394 These functions now nest properly. That is, for every object O, there
3395 is a counter which scm_protect_object(O) increments and
3396 scm_unprotect_object(O) decrements, if the counter is greater than
3397 zero. Every object's counter is zero when it is first created. If an
3398 object's counter is greater than zero, the garbage collector will not
3399 reclaim its storage.
3401 This allows you to use scm_protect_object in your code without
3402 worrying that some other function you call will call
3403 scm_unprotect_object, and allow it to be freed. Assuming that the
3404 functions you call are well-behaved, and unprotect only those objects
3405 they protect, you can follow the same rule and have confidence that
3406 objects will be freed only at appropriate times.
3409 Changes in Guile 1.2 (released Tuesday, June 24 1997):
3411 * Changes to the distribution
3413 ** Nightly snapshots are now available from ftp.red-bean.com.
3414 The old server, ftp.cyclic.com, has been relinquished to its rightful
3417 Nightly snapshots of the Guile development sources are now available via
3418 anonymous FTP from ftp.red-bean.com, as /pub/guile/guile-snap.tar.gz.
3420 Via the web, that's: ftp://ftp.red-bean.com/pub/guile/guile-snap.tar.gz
3421 For getit, that's: ftp.red-bean.com:/pub/guile/guile-snap.tar.gz
3423 ** To run Guile without installing it, the procedure has changed a bit.
3425 If you used a separate build directory to compile Guile, you'll need
3426 to include the build directory in SCHEME_LOAD_PATH, as well as the
3427 source directory. See the `INSTALL' file for examples.
3429 * Changes to the procedure for linking libguile with your programs
3431 ** The standard Guile load path for Scheme code now includes
3432 $(datadir)/guile (usually /usr/local/share/guile). This means that
3433 you can install your own Scheme files there, and Guile will find them.
3434 (Previous versions of Guile only checked a directory whose name
3435 contained the Guile version number, so you had to re-install or move
3436 your Scheme sources each time you installed a fresh version of Guile.)
3438 The load path also includes $(datadir)/guile/site; we recommend
3439 putting individual Scheme files there. If you want to install a
3440 package with multiple source files, create a directory for them under
3443 ** Guile 1.2 will now use the Rx regular expression library, if it is
3444 installed on your system. When you are linking libguile into your own
3445 programs, this means you will have to link against -lguile, -lqt (if
3446 you configured Guile with thread support), and -lrx.
3448 If you are using autoconf to generate configuration scripts for your
3449 application, the following lines should suffice to add the appropriate
3450 libraries to your link command:
3452 ### Find Rx, quickthreads and libguile.
3453 AC_CHECK_LIB(rx, main)
3454 AC_CHECK_LIB(qt, main)
3455 AC_CHECK_LIB(guile, scm_shell)
3457 The Guile 1.2 distribution does not contain sources for the Rx
3458 library, as Guile 1.0 did. If you want to use Rx, you'll need to
3459 retrieve it from a GNU FTP site and install it separately.
3461 * Changes to Scheme functions and syntax
3463 ** The dynamic linking features of Guile are now enabled by default.
3464 You can disable them by giving the `--disable-dynamic-linking' option
3467 (dynamic-link FILENAME)
3469 Find the object file denoted by FILENAME (a string) and link it
3470 into the running Guile application. When everything works out,
3471 return a Scheme object suitable for representing the linked object
3472 file. Otherwise an error is thrown. How object files are
3473 searched is system dependent.
3475 (dynamic-object? VAL)
3477 Determine whether VAL represents a dynamically linked object file.
3479 (dynamic-unlink DYNOBJ)
3481 Unlink the indicated object file from the application. DYNOBJ
3482 should be one of the values returned by `dynamic-link'.
3484 (dynamic-func FUNCTION DYNOBJ)
3486 Search the C function indicated by FUNCTION (a string or symbol)
3487 in DYNOBJ and return some Scheme object that can later be used
3488 with `dynamic-call' to actually call this function. Right now,
3489 these Scheme objects are formed by casting the address of the
3490 function to `long' and converting this number to its Scheme
3493 (dynamic-call FUNCTION DYNOBJ)
3495 Call the C function indicated by FUNCTION and DYNOBJ. The
3496 function is passed no arguments and its return value is ignored.
3497 When FUNCTION is something returned by `dynamic-func', call that
3498 function and ignore DYNOBJ. When FUNCTION is a string (or symbol,
3499 etc.), look it up in DYNOBJ; this is equivalent to
3501 (dynamic-call (dynamic-func FUNCTION DYNOBJ) #f)
3503 Interrupts are deferred while the C function is executing (with
3504 SCM_DEFER_INTS/SCM_ALLOW_INTS).
3506 (dynamic-args-call FUNCTION DYNOBJ ARGS)
3508 Call the C function indicated by FUNCTION and DYNOBJ, but pass it
3509 some arguments and return its return value. The C function is
3510 expected to take two arguments and return an `int', just like
3513 int c_func (int argc, char **argv);
3515 ARGS must be a list of strings and is converted into an array of
3516 `char *'. The array is passed in ARGV and its size in ARGC. The
3517 return value is converted to a Scheme number and returned from the
3518 call to `dynamic-args-call'.
3520 When dynamic linking is disabled or not supported on your system,
3521 the above functions throw errors, but they are still available.
3523 Here is a small example that works on GNU/Linux:
3525 (define libc-obj (dynamic-link "libc.so"))
3526 (dynamic-args-call 'rand libc-obj '())
3528 See the file `libguile/DYNAMIC-LINKING' for additional comments.
3530 ** The #/ syntax for module names is depreciated, and will be removed
3531 in a future version of Guile. Instead of
3539 The latter syntax is more consistent with existing Lisp practice.
3541 ** Guile now does fancier printing of structures. Structures are the
3542 underlying implementation for records, which in turn are used to
3543 implement modules, so all of these object now print differently and in
3544 a more informative way.
3546 The Scheme printer will examine the builtin variable *struct-printer*
3547 whenever it needs to print a structure object. When this variable is
3548 not `#f' it is deemed to be a procedure and will be applied to the
3549 structure object and the output port. When *struct-printer* is `#f'
3550 or the procedure return `#f' the structure object will be printed in
3551 the boring #<struct 80458270> form.
3553 This hook is used by some routines in ice-9/boot-9.scm to implement
3554 type specific printing routines. Please read the comments there about
3557 One of the more specific uses of structs are records. The printing
3558 procedure that could be passed to MAKE-RECORD-TYPE is now actually
3559 called. It should behave like a *struct-printer* procedure (described
3562 ** Guile now supports a new R4RS-compliant syntax for keywords. A
3563 token of the form #:NAME, where NAME has the same syntax as a Scheme
3564 symbol, is the external representation of the keyword named NAME.
3565 Keyword objects print using this syntax as well, so values containing
3566 keyword objects can be read back into Guile. When used in an
3567 expression, keywords are self-quoting objects.
3569 Guile suports this read syntax, and uses this print syntax, regardless
3570 of the current setting of the `keyword' read option. The `keyword'
3571 read option only controls whether Guile recognizes the `:NAME' syntax,
3572 which is incompatible with R4RS. (R4RS says such token represent
3575 ** Guile has regular expression support again. Guile 1.0 included
3576 functions for matching regular expressions, based on the Rx library.
3577 In Guile 1.1, the Guile/Rx interface was removed to simplify the
3578 distribution, and thus Guile had no regular expression support. Guile
3579 1.2 again supports the most commonly used functions, and supports all
3580 of SCSH's regular expression functions.
3582 If your system does not include a POSIX regular expression library,
3583 and you have not linked Guile with a third-party regexp library such as
3584 Rx, these functions will not be available. You can tell whether your
3585 Guile installation includes regular expression support by checking
3586 whether the `*features*' list includes the `regex' symbol.
3588 *** regexp functions
3590 By default, Guile supports POSIX extended regular expressions. That
3591 means that the characters `(', `)', `+' and `?' are special, and must
3592 be escaped if you wish to match the literal characters.
3594 This regular expression interface was modeled after that implemented
3595 by SCSH, the Scheme Shell. It is intended to be upwardly compatible
3596 with SCSH regular expressions.
3598 **** Function: string-match PATTERN STR [START]
3599 Compile the string PATTERN into a regular expression and compare
3600 it with STR. The optional numeric argument START specifies the
3601 position of STR at which to begin matching.
3603 `string-match' returns a "match structure" which describes what,
3604 if anything, was matched by the regular expression. *Note Match
3605 Structures::. If STR does not match PATTERN at all,
3606 `string-match' returns `#f'.
3608 Each time `string-match' is called, it must compile its PATTERN
3609 argument into a regular expression structure. This operation is
3610 expensive, which makes `string-match' inefficient if the same regular
3611 expression is used several times (for example, in a loop). For better
3612 performance, you can compile a regular expression in advance and then
3613 match strings against the compiled regexp.
3615 **** Function: make-regexp STR [FLAGS]
3616 Compile the regular expression described by STR, and return the
3617 compiled regexp structure. If STR does not describe a legal
3618 regular expression, `make-regexp' throws a
3619 `regular-expression-syntax' error.
3621 FLAGS may be the bitwise-or of one or more of the following:
3623 **** Constant: regexp/extended
3624 Use POSIX Extended Regular Expression syntax when interpreting
3625 STR. If not set, POSIX Basic Regular Expression syntax is used.
3626 If the FLAGS argument is omitted, we assume regexp/extended.
3628 **** Constant: regexp/icase
3629 Do not differentiate case. Subsequent searches using the
3630 returned regular expression will be case insensitive.
3632 **** Constant: regexp/newline
3633 Match-any-character operators don't match a newline.
3635 A non-matching list ([^...]) not containing a newline matches a
3638 Match-beginning-of-line operator (^) matches the empty string
3639 immediately after a newline, regardless of whether the FLAGS
3640 passed to regexp-exec contain regexp/notbol.
3642 Match-end-of-line operator ($) matches the empty string
3643 immediately before a newline, regardless of whether the FLAGS
3644 passed to regexp-exec contain regexp/noteol.
3646 **** Function: regexp-exec REGEXP STR [START [FLAGS]]
3647 Match the compiled regular expression REGEXP against `str'. If
3648 the optional integer START argument is provided, begin matching
3649 from that position in the string. Return a match structure
3650 describing the results of the match, or `#f' if no match could be
3653 FLAGS may be the bitwise-or of one or more of the following:
3655 **** Constant: regexp/notbol
3656 The match-beginning-of-line operator always fails to match (but
3657 see the compilation flag regexp/newline above) This flag may be
3658 used when different portions of a string are passed to
3659 regexp-exec and the beginning of the string should not be
3660 interpreted as the beginning of the line.
3662 **** Constant: regexp/noteol
3663 The match-end-of-line operator always fails to match (but see the
3664 compilation flag regexp/newline above)
3666 **** Function: regexp? OBJ
3667 Return `#t' if OBJ is a compiled regular expression, or `#f'
3670 Regular expressions are commonly used to find patterns in one string
3671 and replace them with the contents of another string.
3673 **** Function: regexp-substitute PORT MATCH [ITEM...]
3674 Write to the output port PORT selected contents of the match
3675 structure MATCH. Each ITEM specifies what should be written, and
3676 may be one of the following arguments:
3678 * A string. String arguments are written out verbatim.
3680 * An integer. The submatch with that number is written.
3682 * The symbol `pre'. The portion of the matched string preceding
3683 the regexp match is written.
3685 * The symbol `post'. The portion of the matched string
3686 following the regexp match is written.
3688 PORT may be `#f', in which case nothing is written; instead,
3689 `regexp-substitute' constructs a string from the specified ITEMs
3692 **** Function: regexp-substitute/global PORT REGEXP TARGET [ITEM...]
3693 Similar to `regexp-substitute', but can be used to perform global
3694 substitutions on STR. Instead of taking a match structure as an
3695 argument, `regexp-substitute/global' takes two string arguments: a
3696 REGEXP string describing a regular expression, and a TARGET string
3697 which should be matched against this regular expression.
3699 Each ITEM behaves as in REGEXP-SUBSTITUTE, with the following
3702 * A function may be supplied. When this function is called, it
3703 will be passed one argument: a match structure for a given
3704 regular expression match. It should return a string to be
3705 written out to PORT.
3707 * The `post' symbol causes `regexp-substitute/global' to recurse
3708 on the unmatched portion of STR. This *must* be supplied in
3709 order to perform global search-and-replace on STR; if it is
3710 not present among the ITEMs, then `regexp-substitute/global'
3711 will return after processing a single match.
3713 *** Match Structures
3715 A "match structure" is the object returned by `string-match' and
3716 `regexp-exec'. It describes which portion of a string, if any, matched
3717 the given regular expression. Match structures include: a reference to
3718 the string that was checked for matches; the starting and ending
3719 positions of the regexp match; and, if the regexp included any
3720 parenthesized subexpressions, the starting and ending positions of each
3723 In each of the regexp match functions described below, the `match'
3724 argument must be a match structure returned by a previous call to
3725 `string-match' or `regexp-exec'. Most of these functions return some
3726 information about the original target string that was matched against a
3727 regular expression; we will call that string TARGET for easy reference.
3729 **** Function: regexp-match? OBJ
3730 Return `#t' if OBJ is a match structure returned by a previous
3731 call to `regexp-exec', or `#f' otherwise.
3733 **** Function: match:substring MATCH [N]
3734 Return the portion of TARGET matched by subexpression number N.
3735 Submatch 0 (the default) represents the entire regexp match. If
3736 the regular expression as a whole matched, but the subexpression
3737 number N did not match, return `#f'.
3739 **** Function: match:start MATCH [N]
3740 Return the starting position of submatch number N.
3742 **** Function: match:end MATCH [N]
3743 Return the ending position of submatch number N.
3745 **** Function: match:prefix MATCH
3746 Return the unmatched portion of TARGET preceding the regexp match.
3748 **** Function: match:suffix MATCH
3749 Return the unmatched portion of TARGET following the regexp match.
3751 **** Function: match:count MATCH
3752 Return the number of parenthesized subexpressions from MATCH.
3753 Note that the entire regular expression match itself counts as a
3754 subexpression, and failed submatches are included in the count.
3756 **** Function: match:string MATCH
3757 Return the original TARGET string.
3759 *** Backslash Escapes
3761 Sometimes you will want a regexp to match characters like `*' or `$'
3762 exactly. For example, to check whether a particular string represents
3763 a menu entry from an Info node, it would be useful to match it against
3764 a regexp like `^* [^:]*::'. However, this won't work; because the
3765 asterisk is a metacharacter, it won't match the `*' at the beginning of
3766 the string. In this case, we want to make the first asterisk un-magic.
3768 You can do this by preceding the metacharacter with a backslash
3769 character `\'. (This is also called "quoting" the metacharacter, and
3770 is known as a "backslash escape".) When Guile sees a backslash in a
3771 regular expression, it considers the following glyph to be an ordinary
3772 character, no matter what special meaning it would ordinarily have.
3773 Therefore, we can make the above example work by changing the regexp to
3774 `^\* [^:]*::'. The `\*' sequence tells the regular expression engine
3775 to match only a single asterisk in the target string.
3777 Since the backslash is itself a metacharacter, you may force a
3778 regexp to match a backslash in the target string by preceding the
3779 backslash with itself. For example, to find variable references in a
3780 TeX program, you might want to find occurrences of the string `\let\'
3781 followed by any number of alphabetic characters. The regular expression
3782 `\\let\\[A-Za-z]*' would do this: the double backslashes in the regexp
3783 each match a single backslash in the target string.
3785 **** Function: regexp-quote STR
3786 Quote each special character found in STR with a backslash, and
3787 return the resulting string.
3789 *Very important:* Using backslash escapes in Guile source code (as
3790 in Emacs Lisp or C) can be tricky, because the backslash character has
3791 special meaning for the Guile reader. For example, if Guile encounters
3792 the character sequence `\n' in the middle of a string while processing
3793 Scheme code, it replaces those characters with a newline character.
3794 Similarly, the character sequence `\t' is replaced by a horizontal tab.
3795 Several of these "escape sequences" are processed by the Guile reader
3796 before your code is executed. Unrecognized escape sequences are
3797 ignored: if the characters `\*' appear in a string, they will be
3798 translated to the single character `*'.
3800 This translation is obviously undesirable for regular expressions,
3801 since we want to be able to include backslashes in a string in order to
3802 escape regexp metacharacters. Therefore, to make sure that a backslash
3803 is preserved in a string in your Guile program, you must use *two*
3804 consecutive backslashes:
3806 (define Info-menu-entry-pattern (make-regexp "^\\* [^:]*"))
3808 The string in this example is preprocessed by the Guile reader before
3809 any code is executed. The resulting argument to `make-regexp' is the
3810 string `^\* [^:]*', which is what we really want.
3812 This also means that in order to write a regular expression that
3813 matches a single backslash character, the regular expression string in
3814 the source code must include *four* backslashes. Each consecutive pair
3815 of backslashes gets translated by the Guile reader to a single
3816 backslash, and the resulting double-backslash is interpreted by the
3817 regexp engine as matching a single backslash character. Hence:
3819 (define tex-variable-pattern (make-regexp "\\\\let\\\\=[A-Za-z]*"))
3821 The reason for the unwieldiness of this syntax is historical. Both
3822 regular expression pattern matchers and Unix string processing systems
3823 have traditionally used backslashes with the special meanings described
3824 above. The POSIX regular expression specification and ANSI C standard
3825 both require these semantics. Attempting to abandon either convention
3826 would cause other kinds of compatibility problems, possibly more severe
3827 ones. Therefore, without extending the Scheme reader to support
3828 strings with different quoting conventions (an ungainly and confusing
3829 extension when implemented in other languages), we must adhere to this
3830 cumbersome escape syntax.
3832 * Changes to the gh_ interface
3834 * Changes to the scm_ interface
3836 * Changes to system call interfaces:
3838 ** The value returned by `raise' is now unspecified. It throws an exception
3841 *** A new procedure `sigaction' can be used to install signal handlers
3843 (sigaction signum [action] [flags])
3845 signum is the signal number, which can be specified using the value
3848 If action is omitted, sigaction returns a pair: the CAR is the current
3849 signal hander, which will be either an integer with the value SIG_DFL
3850 (default action) or SIG_IGN (ignore), or the Scheme procedure which
3851 handles the signal, or #f if a non-Scheme procedure handles the
3852 signal. The CDR contains the current sigaction flags for the handler.
3854 If action is provided, it is installed as the new handler for signum.
3855 action can be a Scheme procedure taking one argument, or the value of
3856 SIG_DFL (default action) or SIG_IGN (ignore), or #f to restore
3857 whatever signal handler was installed before sigaction was first used.
3858 Flags can optionally be specified for the new handler (SA_RESTART is
3859 always used if the system provides it, so need not be specified.) The
3860 return value is a pair with information about the old handler as
3863 This interface does not provide access to the "signal blocking"
3864 facility. Maybe this is not needed, since the thread support may
3865 provide solutions to the problem of consistent access to data
3868 *** A new procedure `flush-all-ports' is equivalent to running
3869 `force-output' on every port open for output.
3871 ** Guile now provides information on how it was built, via the new
3872 global variable, %guile-build-info. This variable records the values
3873 of the standard GNU makefile directory variables as an assocation
3874 list, mapping variable names (symbols) onto directory paths (strings).
3875 For example, to find out where the Guile link libraries were
3876 installed, you can say:
3878 guile -c "(display (assq-ref %guile-build-info 'libdir)) (newline)"
3881 * Changes to the scm_ interface
3883 ** The new function scm_handle_by_message_noexit is just like the
3884 existing scm_handle_by_message function, except that it doesn't call
3885 exit to terminate the process. Instead, it prints a message and just
3886 returns #f. This might be a more appropriate catch-all handler for
3887 new dynamic roots and threads.
3890 Changes in Guile 1.1 (released Friday, May 16 1997):
3892 * Changes to the distribution.
3894 The Guile 1.0 distribution has been split up into several smaller
3896 guile-core --- the Guile interpreter itself.
3897 guile-tcltk --- the interface between the Guile interpreter and
3898 Tcl/Tk; Tcl is an interpreter for a stringy language, and Tk
3899 is a toolkit for building graphical user interfaces.
3900 guile-rgx-ctax --- the interface between Guile and the Rx regular
3901 expression matcher, and the translator for the Ctax
3902 programming language. These are packaged together because the
3903 Ctax translator uses Rx to parse Ctax source code.
3905 This NEWS file describes the changes made to guile-core since the 1.0
3908 We no longer distribute the documentation, since it was either out of
3909 date, or incomplete. As soon as we have current documentation, we
3914 * Changes to the stand-alone interpreter
3916 ** guile now accepts command-line arguments compatible with SCSH, Olin
3917 Shivers' Scheme Shell.
3919 In general, arguments are evaluated from left to right, but there are
3920 exceptions. The following switches stop argument processing, and
3921 stash all remaining command-line arguments as the value returned by
3922 the (command-line) function.
3923 -s SCRIPT load Scheme source code from FILE, and exit
3924 -c EXPR evalute Scheme expression EXPR, and exit
3925 -- stop scanning arguments; run interactively
3927 The switches below are processed as they are encountered.
3928 -l FILE load Scheme source code from FILE
3929 -e FUNCTION after reading script, apply FUNCTION to
3930 command line arguments
3931 -ds do -s script at this point
3932 --emacs enable Emacs protocol (experimental)
3933 -h, --help display this help and exit
3934 -v, --version display version information and exit
3935 \ read arguments from following script lines
3937 So, for example, here is a Guile script named `ekko' (thanks, Olin)
3938 which re-implements the traditional "echo" command:
3940 #!/usr/local/bin/guile -s
3943 (map (lambda (arg) (display arg) (display " "))
3947 (main (command-line))
3949 Suppose we invoke this script as follows:
3951 ekko a speckled gecko
3953 Through the magic of Unix script processing (triggered by the `#!'
3954 token at the top of the file), /usr/local/bin/guile receives the
3955 following list of command-line arguments:
3957 ("-s" "./ekko" "a" "speckled" "gecko")
3959 Unix inserts the name of the script after the argument specified on
3960 the first line of the file (in this case, "-s"), and then follows that
3961 with the arguments given to the script. Guile loads the script, which
3962 defines the `main' function, and then applies it to the list of
3963 remaining command-line arguments, ("a" "speckled" "gecko").
3965 In Unix, the first line of a script file must take the following form:
3967 #!INTERPRETER ARGUMENT
3969 where INTERPRETER is the absolute filename of the interpreter
3970 executable, and ARGUMENT is a single command-line argument to pass to
3973 You may only pass one argument to the interpreter, and its length is
3974 limited. These restrictions can be annoying to work around, so Guile
3975 provides a general mechanism (borrowed from, and compatible with,
3976 SCSH) for circumventing them.
3978 If the ARGUMENT in a Guile script is a single backslash character,
3979 `\', Guile will open the script file, parse arguments from its second
3980 and subsequent lines, and replace the `\' with them. So, for example,
3981 here is another implementation of the `ekko' script:
3983 #!/usr/local/bin/guile \
3987 (for-each (lambda (arg) (display arg) (display " "))
3991 If the user invokes this script as follows:
3993 ekko a speckled gecko
3995 Unix expands this into
3997 /usr/local/bin/guile \ ekko a speckled gecko
3999 When Guile sees the `\' argument, it replaces it with the arguments
4000 read from the second line of the script, producing:
4002 /usr/local/bin/guile -e main -s ekko a speckled gecko
4004 This tells Guile to load the `ekko' script, and apply the function
4005 `main' to the argument list ("a" "speckled" "gecko").
4007 Here is how Guile parses the command-line arguments:
4008 - Each space character terminates an argument. This means that two
4009 spaces in a row introduce an empty-string argument.
4010 - The tab character is not permitted (unless you quote it with the
4011 backslash character, as described below), to avoid confusion.
4012 - The newline character terminates the sequence of arguments, and will
4013 also terminate a final non-empty argument. (However, a newline
4014 following a space will not introduce a final empty-string argument;
4015 it only terminates the argument list.)
4016 - The backslash character is the escape character. It escapes
4017 backslash, space, tab, and newline. The ANSI C escape sequences
4018 like \n and \t are also supported. These produce argument
4019 constituents; the two-character combination \n doesn't act like a
4020 terminating newline. The escape sequence \NNN for exactly three
4021 octal digits reads as the character whose ASCII code is NNN. As
4022 above, characters produced this way are argument constituents.
4023 Backslash followed by other characters is not allowed.
4025 * Changes to the procedure for linking libguile with your programs
4027 ** Guile now builds and installs a shared guile library, if your
4028 system support shared libraries. (It still builds a static library on
4029 all systems.) Guile automatically detects whether your system
4030 supports shared libraries. To prevent Guile from buildisg shared
4031 libraries, pass the `--disable-shared' flag to the configure script.
4033 Guile takes longer to compile when it builds shared libraries, because
4034 it must compile every file twice --- once to produce position-
4035 independent object code, and once to produce normal object code.
4037 ** The libthreads library has been merged into libguile.
4039 To link a program against Guile, you now need only link against
4040 -lguile and -lqt; -lthreads is no longer needed. If you are using
4041 autoconf to generate configuration scripts for your application, the
4042 following lines should suffice to add the appropriate libraries to
4045 ### Find quickthreads and libguile.
4046 AC_CHECK_LIB(qt, main)
4047 AC_CHECK_LIB(guile, scm_shell)
4049 * Changes to Scheme functions
4051 ** Guile Scheme's special syntax for keyword objects is now optional,
4052 and disabled by default.
4054 The syntax variation from R4RS made it difficult to port some
4055 interesting packages to Guile. The routines which accepted keyword
4056 arguments (mostly in the module system) have been modified to also
4057 accept symbols whose names begin with `:'.
4059 To change the keyword syntax, you must first import the (ice-9 debug)
4061 (use-modules (ice-9 debug))
4063 Then you can enable the keyword syntax as follows:
4064 (read-set! keywords 'prefix)
4066 To disable keyword syntax, do this:
4067 (read-set! keywords #f)
4069 ** Many more primitive functions accept shared substrings as
4070 arguments. In the past, these functions required normal, mutable
4071 strings as arguments, although they never made use of this
4074 ** The uniform array functions now operate on byte vectors. These
4075 functions are `array-fill!', `serial-array-copy!', `array-copy!',
4076 `serial-array-map', `array-map', `array-for-each', and
4079 ** The new functions `trace' and `untrace' implement simple debugging
4080 support for Scheme functions.
4082 The `trace' function accepts any number of procedures as arguments,
4083 and tells the Guile interpreter to display each procedure's name and
4084 arguments each time the procedure is invoked. When invoked with no
4085 arguments, `trace' returns the list of procedures currently being
4088 The `untrace' function accepts any number of procedures as arguments,
4089 and tells the Guile interpreter not to trace them any more. When
4090 invoked with no arguments, `untrace' untraces all curretly traced
4093 The tracing in Guile has an advantage over most other systems: we
4094 don't create new procedure objects, but mark the procedure objects
4095 themselves. This means that anonymous and internal procedures can be
4098 ** The function `assert-repl-prompt' has been renamed to
4099 `set-repl-prompt!'. It takes one argument, PROMPT.
4100 - If PROMPT is #f, the Guile read-eval-print loop will not prompt.
4101 - If PROMPT is a string, we use it as a prompt.
4102 - If PROMPT is a procedure accepting no arguments, we call it, and
4103 display the result as a prompt.
4104 - Otherwise, we display "> ".
4106 ** The new function `eval-string' reads Scheme expressions from a
4107 string and evaluates them, returning the value of the last expression
4108 in the string. If the string contains no expressions, it returns an
4111 ** The new function `thunk?' returns true iff its argument is a
4112 procedure of zero arguments.
4114 ** `defined?' is now a builtin function, instead of syntax. This
4115 means that its argument should be quoted. It returns #t iff its
4116 argument is bound in the current module.
4118 ** The new syntax `use-modules' allows you to add new modules to your
4119 environment without re-typing a complete `define-module' form. It
4120 accepts any number of module names as arguments, and imports their
4121 public bindings into the current module.
4123 ** The new function (module-defined? NAME MODULE) returns true iff
4124 NAME, a symbol, is defined in MODULE, a module object.
4126 ** The new function `builtin-bindings' creates and returns a hash
4127 table containing copies of all the root module's bindings.
4129 ** The new function `builtin-weak-bindings' does the same as
4130 `builtin-bindings', but creates a doubly-weak hash table.
4132 ** The `equal?' function now considers variable objects to be
4133 equivalent if they have the same name and the same value.
4135 ** The new function `command-line' returns the command-line arguments
4136 given to Guile, as a list of strings.
4138 When using guile as a script interpreter, `command-line' returns the
4139 script's arguments; those processed by the interpreter (like `-s' or
4140 `-c') are omitted. (In other words, you get the normal, expected
4141 behavior.) Any application that uses scm_shell to process its
4142 command-line arguments gets this behavior as well.
4144 ** The new function `load-user-init' looks for a file called `.guile'
4145 in the user's home directory, and loads it if it exists. This is
4146 mostly for use by the code generated by scm_compile_shell_switches,
4147 but we thought it might also be useful in other circumstances.
4149 ** The new function `log10' returns the base-10 logarithm of its
4152 ** Changes to I/O functions
4154 *** The functions `read', `primitive-load', `read-and-eval!', and
4155 `primitive-load-path' no longer take optional arguments controlling
4156 case insensitivity and a `#' parser.
4158 Case sensitivity is now controlled by a read option called
4159 `case-insensitive'. The user can add new `#' syntaxes with the
4160 `read-hash-extend' function (see below).
4162 *** The new function `read-hash-extend' allows the user to change the
4163 syntax of Guile Scheme in a somewhat controlled way.
4165 (read-hash-extend CHAR PROC)
4166 When parsing S-expressions, if we read a `#' character followed by
4167 the character CHAR, use PROC to parse an object from the stream.
4168 If PROC is #f, remove any parsing procedure registered for CHAR.
4170 The reader applies PROC to two arguments: CHAR and an input port.
4172 *** The new functions read-delimited and read-delimited! provide a
4173 general mechanism for doing delimited input on streams.
4175 (read-delimited DELIMS [PORT HANDLE-DELIM])
4176 Read until we encounter one of the characters in DELIMS (a string),
4177 or end-of-file. PORT is the input port to read from; it defaults to
4178 the current input port. The HANDLE-DELIM parameter determines how
4179 the terminating character is handled; it should be one of the
4182 'trim omit delimiter from result
4183 'peek leave delimiter character in input stream
4184 'concat append delimiter character to returned value
4185 'split return a pair: (RESULT . TERMINATOR)
4187 HANDLE-DELIM defaults to 'peek.
4189 (read-delimited! DELIMS BUF [PORT HANDLE-DELIM START END])
4190 A side-effecting variant of `read-delimited'.
4192 The data is written into the string BUF at the indices in the
4193 half-open interval [START, END); the default interval is the whole
4194 string: START = 0 and END = (string-length BUF). The values of
4195 START and END must specify a well-defined interval in BUF, i.e.
4196 0 <= START <= END <= (string-length BUF).
4198 It returns NBYTES, the number of bytes read. If the buffer filled
4199 up without a delimiter character being found, it returns #f. If the
4200 port is at EOF when the read starts, it returns the EOF object.
4202 If an integer is returned (i.e., the read is successfully terminated
4203 by reading a delimiter character), then the HANDLE-DELIM parameter
4204 determines how to handle the terminating character. It is described
4205 above, and defaults to 'peek.
4207 (The descriptions of these functions were borrowed from the SCSH
4208 manual, by Olin Shivers and Brian Carlstrom.)
4210 *** The `%read-delimited!' function is the primitive used to implement
4211 `read-delimited' and `read-delimited!'.
4213 (%read-delimited! DELIMS BUF GOBBLE? [PORT START END])
4215 This returns a pair of values: (TERMINATOR . NUM-READ).
4216 - TERMINATOR describes why the read was terminated. If it is a
4217 character or the eof object, then that is the value that terminated
4218 the read. If it is #f, the function filled the buffer without finding
4219 a delimiting character.
4220 - NUM-READ is the number of characters read into BUF.
4222 If the read is successfully terminated by reading a delimiter
4223 character, then the gobble? parameter determines what to do with the
4224 terminating character. If true, the character is removed from the
4225 input stream; if false, the character is left in the input stream
4226 where a subsequent read operation will retrieve it. In either case,
4227 the character is also the first value returned by the procedure call.
4229 (The descriptions of this function was borrowed from the SCSH manual,
4230 by Olin Shivers and Brian Carlstrom.)
4232 *** The `read-line' and `read-line!' functions have changed; they now
4233 trim the terminator by default; previously they appended it to the
4234 returned string. For the old behavior, use (read-line PORT 'concat).
4236 *** The functions `uniform-array-read!' and `uniform-array-write!' now
4237 take new optional START and END arguments, specifying the region of
4238 the array to read and write.
4240 *** The `ungetc-char-ready?' function has been removed. We feel it's
4241 inappropriate for an interface to expose implementation details this
4244 ** Changes to the Unix library and system call interface
4246 *** The new fcntl function provides access to the Unix `fcntl' system
4249 (fcntl PORT COMMAND VALUE)
4250 Apply COMMAND to PORT's file descriptor, with VALUE as an argument.
4251 Values for COMMAND are:
4253 F_DUPFD duplicate a file descriptor
4254 F_GETFD read the descriptor's close-on-exec flag
4255 F_SETFD set the descriptor's close-on-exec flag to VALUE
4256 F_GETFL read the descriptor's flags, as set on open
4257 F_SETFL set the descriptor's flags, as set on open to VALUE
4258 F_GETOWN return the process ID of a socket's owner, for SIGIO
4259 F_SETOWN set the process that owns a socket to VALUE, for SIGIO
4260 FD_CLOEXEC not sure what this is
4262 For details, see the documentation for the fcntl system call.
4264 *** The arguments to `select' have changed, for compatibility with
4265 SCSH. The TIMEOUT parameter may now be non-integral, yielding the
4266 expected behavior. The MILLISECONDS parameter has been changed to
4267 MICROSECONDS, to more closely resemble the underlying system call.
4268 The RVEC, WVEC, and EVEC arguments can now be vectors; the type of the
4269 corresponding return set will be the same.
4271 *** The arguments to the `mknod' system call have changed. They are
4274 (mknod PATH TYPE PERMS DEV)
4275 Create a new file (`node') in the file system. PATH is the name of
4276 the file to create. TYPE is the kind of file to create; it should
4277 be 'fifo, 'block-special, or 'char-special. PERMS specifies the
4278 permission bits to give the newly created file. If TYPE is
4279 'block-special or 'char-special, DEV specifies which device the
4280 special file refers to; its interpretation depends on the kind of
4281 special file being created.
4283 *** The `fork' function has been renamed to `primitive-fork', to avoid
4284 clashing with various SCSH forks.
4286 *** The `recv' and `recvfrom' functions have been renamed to `recv!'
4287 and `recvfrom!'. They no longer accept a size for a second argument;
4288 you must pass a string to hold the received value. They no longer
4289 return the buffer. Instead, `recv' returns the length of the message
4290 received, and `recvfrom' returns a pair containing the packet's length
4291 and originating address.
4293 *** The file descriptor datatype has been removed, as have the
4294 `read-fd', `write-fd', `close', `lseek', and `dup' functions.
4295 We plan to replace these functions with a SCSH-compatible interface.
4297 *** The `create' function has been removed; it's just a special case
4300 *** There are new functions to break down process termination status
4301 values. In the descriptions below, STATUS is a value returned by
4304 (status:exit-val STATUS)
4305 If the child process exited normally, this function returns the exit
4306 code for the child process (i.e., the value passed to exit, or
4307 returned from main). If the child process did not exit normally,
4308 this function returns #f.
4310 (status:stop-sig STATUS)
4311 If the child process was suspended by a signal, this function
4312 returns the signal that suspended the child. Otherwise, it returns
4315 (status:term-sig STATUS)
4316 If the child process terminated abnormally, this function returns
4317 the signal that terminated the child. Otherwise, this function
4320 POSIX promises that exactly one of these functions will return true on
4321 a valid STATUS value.
4323 These functions are compatible with SCSH.
4325 *** There are new accessors and setters for the broken-out time vectors
4326 returned by `localtime', `gmtime', and that ilk. They are:
4328 Component Accessor Setter
4329 ========================= ============ ============
4330 seconds tm:sec set-tm:sec
4331 minutes tm:min set-tm:min
4332 hours tm:hour set-tm:hour
4333 day of the month tm:mday set-tm:mday
4334 month tm:mon set-tm:mon
4335 year tm:year set-tm:year
4336 day of the week tm:wday set-tm:wday
4337 day in the year tm:yday set-tm:yday
4338 daylight saving time tm:isdst set-tm:isdst
4339 GMT offset, seconds tm:gmtoff set-tm:gmtoff
4340 name of time zone tm:zone set-tm:zone
4342 *** There are new accessors for the vectors returned by `uname',
4343 describing the host system:
4346 ============================================== ================
4347 name of the operating system implementation utsname:sysname
4348 network name of this machine utsname:nodename
4349 release level of the operating system utsname:release
4350 version level of the operating system utsname:version
4351 machine hardware platform utsname:machine
4353 *** There are new accessors for the vectors returned by `getpw',
4354 `getpwnam', `getpwuid', and `getpwent', describing entries from the
4355 system's user database:
4358 ====================== =================
4359 user name passwd:name
4360 user password passwd:passwd
4363 real name passwd:gecos
4364 home directory passwd:dir
4365 shell program passwd:shell
4367 *** There are new accessors for the vectors returned by `getgr',
4368 `getgrnam', `getgrgid', and `getgrent', describing entries from the
4369 system's group database:
4372 ======================= ============
4373 group name group:name
4374 group password group:passwd
4376 group members group:mem
4378 *** There are new accessors for the vectors returned by `gethost',
4379 `gethostbyaddr', `gethostbyname', and `gethostent', describing
4383 ========================= ===============
4384 official name of host hostent:name
4385 alias list hostent:aliases
4386 host address type hostent:addrtype
4387 length of address hostent:length
4388 list of addresses hostent:addr-list
4390 *** There are new accessors for the vectors returned by `getnet',
4391 `getnetbyaddr', `getnetbyname', and `getnetent', describing internet
4395 ========================= ===============
4396 official name of net netent:name
4397 alias list netent:aliases
4398 net number type netent:addrtype
4399 net number netent:net
4401 *** There are new accessors for the vectors returned by `getproto',
4402 `getprotobyname', `getprotobynumber', and `getprotoent', describing
4406 ========================= ===============
4407 official protocol name protoent:name
4408 alias list protoent:aliases
4409 protocol number protoent:proto
4411 *** There are new accessors for the vectors returned by `getserv',
4412 `getservbyname', `getservbyport', and `getservent', describing
4416 ========================= ===============
4417 official service name servent:name
4418 alias list servent:aliases
4419 port number servent:port
4420 protocol to use servent:proto
4422 *** There are new accessors for the sockaddr structures returned by
4423 `accept', `getsockname', `getpeername', `recvfrom!':
4426 ======================================== ===============
4427 address format (`family') sockaddr:fam
4428 path, for file domain addresses sockaddr:path
4429 address, for internet domain addresses sockaddr:addr
4430 TCP or UDP port, for internet sockaddr:port
4432 *** The `getpwent', `getgrent', `gethostent', `getnetent',
4433 `getprotoent', and `getservent' functions now return #f at the end of
4434 the user database. (They used to throw an exception.)
4436 Note that calling MUMBLEent function is equivalent to calling the
4437 corresponding MUMBLE function with no arguments.
4439 *** The `setpwent', `setgrent', `sethostent', `setnetent',
4440 `setprotoent', and `setservent' routines now take no arguments.
4442 *** The `gethost', `getproto', `getnet', and `getserv' functions now
4443 provide more useful information when they throw an exception.
4445 *** The `lnaof' function has been renamed to `inet-lnaof'.
4447 *** Guile now claims to have the `current-time' feature.
4449 *** The `mktime' function now takes an optional second argument ZONE,
4450 giving the time zone to use for the conversion. ZONE should be a
4451 string, in the same format as expected for the "TZ" environment variable.
4453 *** The `strptime' function now returns a pair (TIME . COUNT), where
4454 TIME is the parsed time as a vector, and COUNT is the number of
4455 characters from the string left unparsed. This function used to
4456 return the remaining characters as a string.
4458 *** The `gettimeofday' function has replaced the old `time+ticks' function.
4459 The return value is now (SECONDS . MICROSECONDS); the fractional
4460 component is no longer expressed in "ticks".
4462 *** The `ticks/sec' constant has been removed, in light of the above change.
4464 * Changes to the gh_ interface
4466 ** gh_eval_str() now returns an SCM object which is the result of the
4469 ** gh_scm2str() now copies the Scheme data to a caller-provided C
4472 ** gh_scm2newstr() now makes a C array, copies the Scheme data to it,
4473 and returns the array
4475 ** gh_scm2str0() is gone: there is no need to distinguish
4476 null-terminated from non-null-terminated, since gh_scm2newstr() allows
4477 the user to interpret the data both ways.
4479 * Changes to the scm_ interface
4481 ** The new function scm_symbol_value0 provides an easy way to get a
4482 symbol's value from C code:
4484 SCM scm_symbol_value0 (char *NAME)
4485 Return the value of the symbol named by the null-terminated string
4486 NAME in the current module. If the symbol named NAME is unbound in
4487 the current module, return SCM_UNDEFINED.
4489 ** The new function scm_sysintern0 creates new top-level variables,
4490 without assigning them a value.
4492 SCM scm_sysintern0 (char *NAME)
4493 Create a new Scheme top-level variable named NAME. NAME is a
4494 null-terminated string. Return the variable's value cell.
4496 ** The function scm_internal_catch is the guts of catch. It handles
4497 all the mechanics of setting up a catch target, invoking the catch
4498 body, and perhaps invoking the handler if the body does a throw.
4500 The function is designed to be usable from C code, but is general
4501 enough to implement all the semantics Guile Scheme expects from throw.
4503 TAG is the catch tag. Typically, this is a symbol, but this function
4504 doesn't actually care about that.
4506 BODY is a pointer to a C function which runs the body of the catch;
4507 this is the code you can throw from. We call it like this:
4508 BODY (BODY_DATA, JMPBUF)
4510 BODY_DATA is just the BODY_DATA argument we received; we pass it
4511 through to BODY as its first argument. The caller can make
4512 BODY_DATA point to anything useful that BODY might need.
4513 JMPBUF is the Scheme jmpbuf object corresponding to this catch,
4514 which we have just created and initialized.
4516 HANDLER is a pointer to a C function to deal with a throw to TAG,
4517 should one occur. We call it like this:
4518 HANDLER (HANDLER_DATA, THROWN_TAG, THROW_ARGS)
4520 HANDLER_DATA is the HANDLER_DATA argument we recevied; it's the
4521 same idea as BODY_DATA above.
4522 THROWN_TAG is the tag that the user threw to; usually this is
4523 TAG, but it could be something else if TAG was #t (i.e., a
4524 catch-all), or the user threw to a jmpbuf.
4525 THROW_ARGS is the list of arguments the user passed to the THROW
4528 BODY_DATA is just a pointer we pass through to BODY. HANDLER_DATA
4529 is just a pointer we pass through to HANDLER. We don't actually
4530 use either of those pointers otherwise ourselves. The idea is
4531 that, if our caller wants to communicate something to BODY or
4532 HANDLER, it can pass a pointer to it as MUMBLE_DATA, which BODY and
4533 HANDLER can then use. Think of it as a way to make BODY and
4534 HANDLER closures, not just functions; MUMBLE_DATA points to the
4537 Of course, it's up to the caller to make sure that any data a
4538 MUMBLE_DATA needs is protected from GC. A common way to do this is
4539 to make MUMBLE_DATA a pointer to data stored in an automatic
4540 structure variable; since the collector must scan the stack for
4541 references anyway, this assures that any references in MUMBLE_DATA
4544 ** The new function scm_internal_lazy_catch is exactly like
4545 scm_internal_catch, except:
4547 - It does not unwind the stack (this is the major difference).
4548 - If handler returns, its value is returned from the throw.
4549 - BODY always receives #f as its JMPBUF argument (since there's no
4550 jmpbuf associated with a lazy catch, because we don't unwind the
4553 ** scm_body_thunk is a new body function you can pass to
4554 scm_internal_catch if you want the body to be like Scheme's `catch'
4555 --- a thunk, or a function of one argument if the tag is #f.
4557 BODY_DATA is a pointer to a scm_body_thunk_data structure, which
4558 contains the Scheme procedure to invoke as the body, and the tag
4559 we're catching. If the tag is #f, then we pass JMPBUF (created by
4560 scm_internal_catch) to the body procedure; otherwise, the body gets
4563 ** scm_handle_by_proc is a new handler function you can pass to
4564 scm_internal_catch if you want the handler to act like Scheme's catch
4565 --- call a procedure with the tag and the throw arguments.
4567 If the user does a throw to this catch, this function runs a handler
4568 procedure written in Scheme. HANDLER_DATA is a pointer to an SCM
4569 variable holding the Scheme procedure object to invoke. It ought to
4570 be a pointer to an automatic variable (i.e., one living on the stack),
4571 or the procedure object should be otherwise protected from GC.
4573 ** scm_handle_by_message is a new handler function to use with
4574 `scm_internal_catch' if you want Guile to print a message and die.
4575 It's useful for dealing with throws to uncaught keys at the top level.
4577 HANDLER_DATA, if non-zero, is assumed to be a char * pointing to a
4578 message header to print; if zero, we use "guile" instead. That
4579 text is followed by a colon, then the message described by ARGS.
4581 ** The return type of scm_boot_guile is now void; the function does
4582 not return a value, and indeed, never returns at all.
4584 ** The new function scm_shell makes it easy for user applications to
4585 process command-line arguments in a way that is compatible with the
4586 stand-alone guile interpreter (which is in turn compatible with SCSH,
4589 To use the scm_shell function, first initialize any guile modules
4590 linked into your application, and then call scm_shell with the values
4591 of ARGC and ARGV your `main' function received. scm_shell will add
4592 any SCSH-style meta-arguments from the top of the script file to the
4593 argument vector, and then process the command-line arguments. This
4594 generally means loading a script file or starting up an interactive
4595 command interpreter. For details, see "Changes to the stand-alone
4598 ** The new functions scm_get_meta_args and scm_count_argv help you
4599 implement the SCSH-style meta-argument, `\'.
4601 char **scm_get_meta_args (int ARGC, char **ARGV)
4602 If the second element of ARGV is a string consisting of a single
4603 backslash character (i.e. "\\" in Scheme notation), open the file
4604 named by the following argument, parse arguments from it, and return
4605 the spliced command line. The returned array is terminated by a
4608 For details of argument parsing, see above, under "guile now accepts
4609 command-line arguments compatible with SCSH..."
4611 int scm_count_argv (char **ARGV)
4612 Count the arguments in ARGV, assuming it is terminated by a null
4615 For an example of how these functions might be used, see the source
4616 code for the function scm_shell in libguile/script.c.
4618 You will usually want to use scm_shell instead of calling this
4621 ** The new function scm_compile_shell_switches turns an array of
4622 command-line arguments into Scheme code to carry out the actions they
4623 describe. Given ARGC and ARGV, it returns a Scheme expression to
4624 evaluate, and calls scm_set_program_arguments to make any remaining
4625 command-line arguments available to the Scheme code. For example,
4626 given the following arguments:
4628 -e main -s ekko a speckled gecko
4630 scm_set_program_arguments will return the following expression:
4632 (begin (load "ekko") (main (command-line)) (quit))
4634 You will usually want to use scm_shell instead of calling this
4637 ** The function scm_shell_usage prints a usage message appropriate for
4638 an interpreter that uses scm_compile_shell_switches to handle its
4639 command-line arguments.
4641 void scm_shell_usage (int FATAL, char *MESSAGE)
4642 Print a usage message to the standard error output. If MESSAGE is
4643 non-zero, write it before the usage message, followed by a newline.
4644 If FATAL is non-zero, exit the process, using FATAL as the
4645 termination status. (If you want to be compatible with Guile,
4646 always use 1 as the exit status when terminating due to command-line
4649 You will usually want to use scm_shell instead of calling this
4652 ** scm_eval_0str now returns SCM_UNSPECIFIED if the string contains no
4653 expressions. It used to return SCM_EOL. Earth-shattering.
4655 ** The macros for declaring scheme objects in C code have been
4656 rearranged slightly. They are now:
4658 SCM_SYMBOL (C_NAME, SCHEME_NAME)
4659 Declare a static SCM variable named C_NAME, and initialize it to
4660 point to the Scheme symbol whose name is SCHEME_NAME. C_NAME should
4661 be a C identifier, and SCHEME_NAME should be a C string.
4663 SCM_GLOBAL_SYMBOL (C_NAME, SCHEME_NAME)
4664 Just like SCM_SYMBOL, but make C_NAME globally visible.
4666 SCM_VCELL (C_NAME, SCHEME_NAME)
4667 Create a global variable at the Scheme level named SCHEME_NAME.
4668 Declare a static SCM variable named C_NAME, and initialize it to
4669 point to the Scheme variable's value cell.
4671 SCM_GLOBAL_VCELL (C_NAME, SCHEME_NAME)
4672 Just like SCM_VCELL, but make C_NAME globally visible.
4674 The `guile-snarf' script writes initialization code for these macros
4675 to its standard output, given C source code as input.
4677 The SCM_GLOBAL macro is gone.
4679 ** The scm_read_line and scm_read_line_x functions have been replaced
4680 by Scheme code based on the %read-delimited! procedure (known to C
4681 code as scm_read_delimited_x). See its description above for more
4684 ** The function scm_sys_open has been renamed to scm_open. It now
4685 returns a port instead of an FD object.
4687 * The dynamic linking support has changed. For more information, see
4688 libguile/DYNAMIC-LINKING.
4693 User-visible changes from Thursday, September 5, 1996 until Guile 1.0
4696 * Changes to the 'guile' program:
4698 ** Guile now loads some new files when it starts up. Guile first
4699 searches the load path for init.scm, and loads it if found. Then, if
4700 Guile is not being used to execute a script, and the user's home
4701 directory contains a file named `.guile', Guile loads that.
4703 ** You can now use Guile as a shell script interpreter.
4705 To paraphrase the SCSH manual:
4707 When Unix tries to execute an executable file whose first two
4708 characters are the `#!', it treats the file not as machine code to
4709 be directly executed by the native processor, but as source code
4710 to be executed by some interpreter. The interpreter to use is
4711 specified immediately after the #! sequence on the first line of
4712 the source file. The kernel reads in the name of the interpreter,
4713 and executes that instead. It passes the interpreter the source
4714 filename as its first argument, with the original arguments
4715 following. Consult the Unix man page for the `exec' system call
4716 for more information.
4718 Now you can use Guile as an interpreter, using a mechanism which is a
4719 compatible subset of that provided by SCSH.
4721 Guile now recognizes a '-s' command line switch, whose argument is the
4722 name of a file of Scheme code to load. It also treats the two
4723 characters `#!' as the start of a comment, terminated by `!#'. Thus,
4724 to make a file of Scheme code directly executable by Unix, insert the
4725 following two lines at the top of the file:
4727 #!/usr/local/bin/guile -s
4730 Guile treats the argument of the `-s' command-line switch as the name
4731 of a file of Scheme code to load, and treats the sequence `#!' as the
4732 start of a block comment, terminated by `!#'.
4734 For example, here's a version of 'echo' written in Scheme:
4736 #!/usr/local/bin/guile -s
4738 (let loop ((args (cdr (program-arguments))))
4741 (display (car args))
4742 (if (pair? (cdr args))
4744 (loop (cdr args)))))
4747 Why does `#!' start a block comment terminated by `!#', instead of the
4748 end of the line? That is the notation SCSH uses, and although we
4749 don't yet support the other SCSH features that motivate that choice,
4750 we would like to be backward-compatible with any existing Guile
4751 scripts once we do. Furthermore, if the path to Guile on your system
4752 is too long for your kernel, you can start the script with this
4756 exec /really/long/path/to/guile -s "$0" ${1+"$@"}
4759 Note that some very old Unix systems don't support the `#!' syntax.
4762 ** You can now run Guile without installing it.
4764 Previous versions of the interactive Guile interpreter (`guile')
4765 couldn't start up unless Guile's Scheme library had been installed;
4766 they used the value of the environment variable `SCHEME_LOAD_PATH'
4767 later on in the startup process, but not to find the startup code
4768 itself. Now Guile uses `SCHEME_LOAD_PATH' in all searches for Scheme
4771 To run Guile without installing it, build it in the normal way, and
4772 then set the environment variable `SCHEME_LOAD_PATH' to a
4773 colon-separated list of directories, including the top-level directory
4774 of the Guile sources. For example, if you unpacked Guile so that the
4775 full filename of this NEWS file is /home/jimb/guile-1.0b3/NEWS, then
4778 export SCHEME_LOAD_PATH=/home/jimb/my-scheme:/home/jimb/guile-1.0b3
4781 ** Guile's read-eval-print loop no longer prints #<unspecified>
4782 results. If the user wants to see this, she can evaluate the
4783 expression (assert-repl-print-unspecified #t), perhaps in her startup
4786 ** Guile no longer shows backtraces by default when an error occurs;
4787 however, it does display a message saying how to get one, and how to
4788 request that they be displayed by default. After an error, evaluate
4790 to see a backtrace, and
4791 (debug-enable 'backtrace)
4792 to see them by default.
4796 * Changes to Guile Scheme:
4798 ** Guile now distinguishes between #f and the empty list.
4800 This is for compatibility with the IEEE standard, the (possibly)
4801 upcoming Revised^5 Report on Scheme, and many extant Scheme
4804 Guile used to have #f and '() denote the same object, to make Scheme's
4805 type system more compatible with Emacs Lisp's. However, the change
4806 caused too much trouble for Scheme programmers, and we found another
4807 way to reconcile Emacs Lisp with Scheme that didn't require this.
4810 ** Guile's delq, delv, delete functions, and their destructive
4811 counterparts, delq!, delv!, and delete!, now remove all matching
4812 elements from the list, not just the first. This matches the behavior
4813 of the corresponding Emacs Lisp functions, and (I believe) the Maclisp
4814 functions which inspired them.
4816 I recognize that this change may break code in subtle ways, but it
4817 seems best to make the change before the FSF's first Guile release,
4821 ** The compiled-library-path function has been deleted from libguile.
4823 ** The facilities for loading Scheme source files have changed.
4825 *** The variable %load-path now tells Guile which directories to search
4826 for Scheme code. Its value is a list of strings, each of which names
4829 *** The variable %load-extensions now tells Guile which extensions to
4830 try appending to a filename when searching the load path. Its value
4831 is a list of strings. Its default value is ("" ".scm").
4833 *** (%search-load-path FILENAME) searches the directories listed in the
4834 value of the %load-path variable for a Scheme file named FILENAME,
4835 with all the extensions listed in %load-extensions. If it finds a
4836 match, then it returns its full filename. If FILENAME is absolute, it
4837 returns it unchanged. Otherwise, it returns #f.
4839 %search-load-path will not return matches that refer to directories.
4841 *** (primitive-load FILENAME :optional CASE-INSENSITIVE-P SHARP)
4842 uses %seach-load-path to find a file named FILENAME, and loads it if
4843 it finds it. If it can't read FILENAME for any reason, it throws an
4846 The arguments CASE-INSENSITIVE-P and SHARP are interpreted as by the
4849 *** load uses the same searching semantics as primitive-load.
4851 *** The functions %try-load, try-load-with-path, %load, load-with-path,
4852 basic-try-load-with-path, basic-load-with-path, try-load-module-with-
4853 path, and load-module-with-path have been deleted. The functions
4854 above should serve their purposes.
4856 *** If the value of the variable %load-hook is a procedure,
4857 `primitive-load' applies its value to the name of the file being
4858 loaded (without the load path directory name prepended). If its value
4859 is #f, it is ignored. Otherwise, an error occurs.
4861 This is mostly useful for printing load notification messages.
4864 ** The function `eval!' is no longer accessible from the scheme level.
4865 We can't allow operations which introduce glocs into the scheme level,
4866 because Guile's type system can't handle these as data. Use `eval' or
4867 `read-and-eval!' (see below) as replacement.
4869 ** The new function read-and-eval! reads an expression from PORT,
4870 evaluates it, and returns the result. This is more efficient than
4871 simply calling `read' and `eval', since it is not necessary to make a
4872 copy of the expression for the evaluator to munge.
4874 Its optional arguments CASE_INSENSITIVE_P and SHARP are interpreted as
4875 for the `read' function.
4878 ** The function `int?' has been removed; its definition was identical
4879 to that of `integer?'.
4881 ** The functions `<?', `<?', `<=?', `=?', `>?', and `>=?'. Code should
4882 use the R4RS names for these functions.
4884 ** The function object-properties no longer returns the hash handle;
4885 it simply returns the object's property list.
4887 ** Many functions have been changed to throw errors, instead of
4888 returning #f on failure. The point of providing exception handling in
4889 the language is to simplify the logic of user code, but this is less
4890 useful if Guile's primitives don't throw exceptions.
4892 ** The function `fileno' has been renamed from `%fileno'.
4894 ** The function primitive-mode->fdes returns #t or #f now, not 1 or 0.
4897 * Changes to Guile's C interface:
4899 ** The library's initialization procedure has been simplified.
4900 scm_boot_guile now has the prototype:
4902 void scm_boot_guile (int ARGC,
4904 void (*main_func) (),
4907 scm_boot_guile calls MAIN_FUNC, passing it CLOSURE, ARGC, and ARGV.
4908 MAIN_FUNC should do all the work of the program (initializing other
4909 packages, reading user input, etc.) before returning. When MAIN_FUNC
4910 returns, call exit (0); this function never returns. If you want some
4911 other exit value, MAIN_FUNC may call exit itself.
4913 scm_boot_guile arranges for program-arguments to return the strings
4914 given by ARGC and ARGV. If MAIN_FUNC modifies ARGC/ARGV, should call
4915 scm_set_program_arguments with the final list, so Scheme code will
4916 know which arguments have been processed.
4918 scm_boot_guile establishes a catch-all catch handler which prints an
4919 error message and exits the process. This means that Guile exits in a
4920 coherent way when system errors occur and the user isn't prepared to
4921 handle it. If the user doesn't like this behavior, they can establish
4922 their own universal catcher in MAIN_FUNC to shadow this one.
4924 Why must the caller do all the real work from MAIN_FUNC? The garbage
4925 collector assumes that all local variables of type SCM will be above
4926 scm_boot_guile's stack frame on the stack. If you try to manipulate
4927 SCM values after this function returns, it's the luck of the draw
4928 whether the GC will be able to find the objects you allocate. So,
4929 scm_boot_guile function exits, rather than returning, to discourage
4930 people from making that mistake.
4932 The IN, OUT, and ERR arguments were removed; there are other
4933 convenient ways to override these when desired.
4935 The RESULT argument was deleted; this function should never return.
4937 The BOOT_CMD argument was deleted; the MAIN_FUNC argument is more
4941 ** Guile's header files should no longer conflict with your system's
4944 In order to compile code which #included <libguile.h>, previous
4945 versions of Guile required you to add a directory containing all the
4946 Guile header files to your #include path. This was a problem, since
4947 Guile's header files have names which conflict with many systems'
4950 Now only <libguile.h> need appear in your #include path; you must
4951 refer to all Guile's other header files as <libguile/mumble.h>.
4952 Guile's installation procedure puts libguile.h in $(includedir), and
4953 the rest in $(includedir)/libguile.
4956 ** Two new C functions, scm_protect_object and scm_unprotect_object,
4957 have been added to the Guile library.
4959 scm_protect_object (OBJ) protects OBJ from the garbage collector.
4960 OBJ will not be freed, even if all other references are dropped,
4961 until someone does scm_unprotect_object (OBJ). Both functions
4964 Note that calls to scm_protect_object do not nest. You can call
4965 scm_protect_object any number of times on a given object, and the
4966 next call to scm_unprotect_object will unprotect it completely.
4968 Basically, scm_protect_object and scm_unprotect_object just
4969 maintain a list of references to things. Since the GC knows about
4970 this list, all objects it mentions stay alive. scm_protect_object
4971 adds its argument to the list; scm_unprotect_object remove its
4972 argument from the list.
4975 ** scm_eval_0str now returns the value of the last expression
4978 ** The new function scm_read_0str reads an s-expression from a
4979 null-terminated string, and returns it.
4981 ** The new function `scm_stdio_to_port' converts a STDIO file pointer
4982 to a Scheme port object.
4984 ** The new function `scm_set_program_arguments' allows C code to set
4985 the value returned by the Scheme `program-arguments' function.
4990 * Guile no longer includes sophisticated Tcl/Tk support.
4992 The old Tcl/Tk support was unsatisfying to us, because it required the
4993 user to link against the Tcl library, as well as Tk and Guile. The
4994 interface was also un-lispy, in that it preserved Tcl/Tk's practice of
4995 referring to widgets by names, rather than exporting widgets to Scheme
4996 code as a special datatype.
4998 In the Usenix Tk Developer's Workshop held in July 1996, the Tcl/Tk
4999 maintainers described some very interesting changes in progress to the
5000 Tcl/Tk internals, which would facilitate clean interfaces between lone
5001 Tk and other interpreters --- even for garbage-collected languages
5002 like Scheme. They expected the new Tk to be publicly available in the
5005 Since it seems that Guile might soon have a new, cleaner interface to
5006 lone Tk, and that the old Guile/Tk glue code would probably need to be
5007 completely rewritten, we (Jim Blandy and Richard Stallman) have
5008 decided not to support the old code. We'll spend the time instead on
5009 a good interface to the newer Tk, as soon as it is available.
5011 Until then, gtcltk-lib provides trivial, low-maintenance functionality.
5014 Copyright information:
5016 Copyright (C) 1996,1997 Free Software Foundation, Inc.
5018 Permission is granted to anyone to make or distribute verbatim copies
5019 of this document as received, in any medium, provided that the
5020 copyright notice and this permission notice are preserved,
5021 thus giving the recipient permission to redistribute in turn.
5023 Permission is granted to distribute modified versions
5024 of this document, or of portions of it,
5025 under the above conditions, provided also that they
5026 carry prominent notices stating who last changed them.
5031 paragraph-separate: "[
\f]*$"