Guile NEWS --- history of user-visible changes.
-Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
See the end for copying conditions.
-Please send Guile bug reports to bug-guile@gnu.org. Note that you
-must be subscribed to this list first, in order to successfully send a
-report to it.
+Please send Guile bug reports to bug-guile@gnu.org.
+
+
+Note: During the 1.9 series, we will keep an incremental NEWS for the
+latest prerelease, and a full NEWS corresponding to 1.8 -> 2.0.
+
+Changes since the 1.9.15 prerelease:
+
+** `unquote' and `unquote-splicing' accept multiple expressions
+
+As per the R6RS, these syntax operators can now accept any number of
+expressions to unquote.
+
+** `getopt-long' parsing errors throw to `quit', not `misc-error'
+
+This change should inhibit backtraces on argument parsing errors.
+`getopt-long' has been modified to print out the error that it throws
+itself.
+
+** New helpers: `print-exception', `set-exception-printer!'
+
+These functions implement an extensible exception printer. Guile
+registers printers for all of the exceptions it throws. Users may add
+their own printers. There is also `scm_print_exception', for use by C
+programs. Pleasantly, this allows SRFI-35 and R6RS exceptions to be
+printed appropriately.
+
+** `positions' reader option enabled by default
+
+This change allows primitive-load without --auto-compile to also
+propagate source information through the expander, for better errors and
+to let macros know their source locations. The compiler was already
+turning it on anyway.
+
+** `load' is a macro (!) that resolves paths relative to source file dir
+
+The familiar Schem `load' procedure is now a macro that captures the
+name of the source file being expanded, and dispatches to the new
+`load-in-vicinity'. Referencing `load' by bare name returns a closure
+that embeds the current source file name.
+
+This fix allows `load' of relative paths to be resolved with respect to
+the location of the file that calls `load'.
+
+** "autocompile" -> "auto-compile"
+
+The "--autocompile" and "--no-autocompile" arguments were renamed to
+have a dash, for consistency with the GUILE_AUTO_COMPILE environment
+variable, and with common conventions. A number of variables were also
+appropriately renamed.
+
+** `scm_primitive_load' defaults to UTF-8, not Latin-1
+
+Like `compile-file', `primitive-load' now defaults to UTF-8.
+
+** Warning now available for auto-compiled files.
+
+See the `%auto-compilation-options' variable. Warnings at
+auto-compilation time are preceded with the `*current-warning-prefix*'
+(a fluid).
+
+** Deprecated: primitive properties
+
+The `primitive-make-property', `primitive-property-set!',
+`primitive-property-ref', and `primitive-property-del!' procedures were
+crufty and only used to implement object properties, which has a new,
+threadsafe implementation. Use object properties or weak hash tables
+instead.
+
+** New syntax: define-once
+
+`define-once' is like Lisp's `defvar': it creates a toplevel binding,
+but only if one does not exist already.
+
+** Added four new sets of fast quotient and remainder operators
+
+Added four new sets of fast quotient and remainder operators with
+different semantics than the R5RS operators. They support not only
+integers, but all reals, including exact rationals and inexact
+floating point numbers.
+
+These procedures accept two real numbers N and D, where the divisor D
+must be non-zero. Each set of operators computes an integer quotient
+Q and a real remainder R such that N = Q*D + R and |R| < |D|. They
+differ only in how N/D is rounded to produce Q.
+
+`floor-quotient' and `floor-remainder' compute Q and R, respectively,
+where Q has been rounded toward negative infinity. `floor/' returns
+both Q and R, and is more efficient than computing each separately.
+Note that when applied to integers, `floor-remainder' is equivalent to
+the R5RS integer-only `modulo' operator. `ceiling-quotient',
+`ceiling-remainder', and `ceiling/' are similar except that Q is
+rounded toward positive infinity.
+
+For `truncate-quotient', `truncate-remainder', and `truncate/', Q is
+rounded toward zero. Note that when applied to integers,
+`truncate-quotient' and `truncate-remainder' are equivalent to the
+R5RS integer-only operators `quotient' and `remainder'.
+
+For `round-quotient', `round-remainder', and `round/', Q is rounded to
+the nearest integer, with ties going to the nearest even integer.
+
+** Improved exactness handling for complex number parsing
+
+When parsing non-real complex numbers, exactness specifiers are now
+applied to each component, as is done in PLT Scheme. For complex
+numbers written in rectangular form, exactness specifiers are applied
+to the real and imaginary parts before calling scm_make_rectangular.
+For complex numbers written in polar form, exactness specifiers are
+applied to the magnitude and angle before calling scm_make_polar.
+
+Previously, exactness specifiers were applied to the number as a whole
+_after_ calling scm_make_rectangular or scm_make_polar.
+
+For example, (string->number "#i5.0+0i") now does the equivalent of:
+
+ (make-rectangular (exact->inexact 5.0) (exact->inexact 0))
+
+which yields 5.0+0.0i. Previously it did the equivalent of:
+
+ (exact->inexact (make-rectangular 5.0 0))
+
+which yielded 5.0.
\f
-Changes in 1.9.0:
+Changes in 1.9.x (since the 1.8.x series):
+
+* New modules (see the manual for details)
+
+** `(srfi srfi-18)', more sophisticated multithreading support
+** `(srfi srfi-27)', sources of random bits
+** `(srfi srfi-38)', External Representation for Data With Shared Structure
+** `(srfi srfi-42)', eager comprehensions
+** `(srfi srfi-45)', primitives for expressing iterative lazy algorithms
+** `(srfi srfi-67)', compare procedures
+** `(ice-9 i18n)', internationalization support
+** `(ice-9 futures)', fine-grain parallelism
+** `(rnrs bytevectors)', the R6RS bytevector API
+** `(rnrs io ports)', a subset of the R6RS I/O port API
+** `(system xref)', a cross-referencing facility (FIXME undocumented)
+** `(ice-9 vlist)', lists with constant-time random access; hash lists
+** `(system foreign)', foreign function interface
+** `(sxml match)', a pattern matcher for SXML
+** `(srfi srfi-9 gnu)', extensions to the SRFI-9 record library
+** `(system vm coverage)', a line-by-line code coverage library
+** `(web uri)', URI data type, parser, and unparser
+** `(web http)', HTTP header parsers and unparsers
+** `(web request)', HTTP request data type, reader, and writer
+** `(web response)', HTTP response data type, reader, and writer
+** `(web server)', Generic HTTP server
+** `(ice-9 poll)', a poll wrapper
+** `(web server http)', HTTP-over-TCP web server implementation
+
+** Replaced `(ice-9 match)' with Alex Shinn's compatible, hygienic matcher.
+
+Guile's copy of Andrew K. Wright's `match' library has been replaced by
+a compatible hygienic implementation by Alex Shinn. It is now
+documented, see "Pattern Matching" in the manual.
+
+Compared to Andrew K. Wright's `match', the new `match' lacks
+`match-define', `match:error-control', `match:set-error-control',
+`match:error', `match:set-error', and all structure-related procedures.
+
+** Imported statprof, SSAX, and texinfo modules from Guile-Lib
+
+The statprof statistical profiler, the SSAX XML toolkit, and the texinfo
+toolkit from Guile-Lib have been imported into Guile proper. See
+"Standard Library" in the manual for more details.
+
+** Integration of lalr-scm, a parser generator
+
+Guile has included Dominique Boucher's fine `lalr-scm' parser generator
+as `(system base lalr)'. See "LALR(1) Parsing" in the manual, for more
+information.
+
+* Changes to the stand-alone interpreter
+
+** Guile now can compile Scheme to bytecode for a custom virtual machine.
+
+Compiled code loads much faster than Scheme source code, and runs around
+3 or 4 times as fast, generating much less garbage in the process.
+
+** Evaluating Scheme code does not use the C stack.
+
+Besides when compiling Guile itself, Guile no longer uses a recursive C
+function as an evaluator. This obviates the need to check the C stack
+pointer for overflow. Continuations still capture the C stack, however.
+
+** New environment variables: GUILE_LOAD_COMPILED_PATH,
+ GUILE_SYSTEM_LOAD_COMPILED_PATH
+
+GUILE_LOAD_COMPILED_PATH is for compiled files what GUILE_LOAD_PATH is
+for source files. It is a different path, however, because compiled
+files are architecture-specific. GUILE_SYSTEM_LOAD_COMPILED_PATH is like
+GUILE_SYSTEM_PATH.
+
+** New read-eval-print loop (REPL) implementation
+
+Running Guile with no arguments drops the user into the new REPL. See
+"Using Guile Interactively" in the manual, for more information.
+
+** Remove old Emacs interface
+
+Guile had an unused `--emacs' command line argument that was supposed to
+help when running Guile inside Emacs. This option has been removed, and
+the helper functions `named-module-use!' and `load-emacs-interface' have
+been deprecated.
+
+** Add `(system repl server)' module and `--listen' command-line argument
+
+The `(system repl server)' module exposes procedures to listen on
+sockets for connections, and serve REPLs to those clients. The --listen
+command-line argument allows any Guile program to thus be remotely
+debuggable.
+
+See "Invoking Guile" for more information on `--listen'.
+
+** Command line additions
+
+The guile binary now supports a new switch "-x", which can be used to
+extend the list of filename extensions tried when loading files
+(%load-extensions).
+
+** New reader options: `square-brackets', `r6rs-hex-escapes',
+ `hungry-eol-escapes'
+
+The reader supports a new option (changeable via `read-options'),
+`square-brackets', which instructs it to interpret square brackets as
+parentheses. This option is on by default.
+
+When the new `r6rs-hex-escapes' reader option is enabled, the reader
+will recognize string escape sequences as defined in R6RS. R6RS string
+escape sequences are incompatible with Guile's existing escapes, though,
+so this option is off by default.
+
+Additionally, Guile follows the R6RS newline escaping rules when the
+`hungry-eol-escapes' option is enabled.
+
+See "String Syntax" in the manual, for more information.
+
+** Function profiling and tracing at the REPL
+
+The `,profile FORM' REPL meta-command can now be used to statistically
+profile execution of a form, to see which functions are taking the most
+time. See `,help profile' for more information.
+
+Similarly, `,trace FORM' traces all function applications that occur
+during the execution of `FORM'. See `,help trace' for more information.
+
+** Recursive debugging REPL on error
+
+When Guile sees an error at the REPL, instead of saving the stack, Guile
+will directly enter a recursive REPL in the dynamic context of the
+error. See "Error Handling" in the manual, for more information.
+
+A recursive REPL is the same as any other REPL, except that it
+has been augmented with debugging information, so that one can inspect
+the context of the error. The debugger has been integrated with the REPL
+via a set of debugging meta-commands.
+
+For example, one may access a backtrace with `,backtrace' (or
+`,bt'). See "Interactive Debugging" in the manual, for more
+information.
+
+** New `guile-tools' commands: `compile', `disassemble'
+
+Pass the `--help' command-line option to these commands for more
+information.
+
+** Guile now adds its install prefix to the LTDL_LIBRARY_PATH
+
+Users may now install Guile to nonstandard prefixes and just run
+`/path/to/bin/guile', instead of also having to set LTDL_LIBRARY_PATH to
+include `/path/to/lib'.
+
+** Guile's Emacs integration is now more keyboard-friendly
+
+Backtraces may now be disclosed with the keyboard in addition to the
+mouse.
+
+** Load path change: search in version-specific paths before site paths
+
+When looking for a module, Guile now searches first in Guile's
+version-specific path (the library path), *then* in the site dir. This
+allows Guile's copy of SSAX to override any Guile-Lib copy the user has
+installed. Also it should cut the number of `stat' system calls by half,
+in the common case.
+
+** Value history in the REPL on by default
+
+By default, the REPL will save computed values in variables like `$1',
+`$2', and the like. There are programmatic and interactive interfaces to
+control this. See "Value History" in the manual, for more information.
+
+** Readline tab completion for arguments
+
+When readline is enabled, tab completion works for arguments too, not
+just for the operator position.
+
+** Expression-oriented readline history
+
+Guile's readline history now tries to operate on expressions instead of
+input lines. Let us know what you think!
+
+** Interactive Guile follows GNU conventions
+
+As recommended by the GPL, Guile now shows a brief copyright and
+warranty disclaimer on startup, along with pointers to more information.
+
+* Changes to Scheme functions and syntax
+
+** Support for R6RS libraries
+
+The `library' and `import' forms from the latest Scheme report have been
+added to Guile, in such a way that R6RS libraries share a namespace with
+Guile modules. R6RS modules may import Guile modules, and are available
+for Guile modules to import via use-modules and all the rest. See "R6RS
+Libraries" in the manual for more information.
+
+** Implementations of R6RS libraries
+
+Guile now has implementations for all of the libraries defined in the
+R6RS. Thanks to Julian Graham for this excellent hack. See "R6RS
+Standard Libraries" in the manual for a full list of libraries.
+
+** Partial R6RS compatibility
+
+Guile now has enough support for R6RS to run a reasonably large subset
+of R6RS programs.
+
+Guile is not fully R6RS compatible. Many incompatibilities are simply
+bugs, though some parts of Guile will remain R6RS-incompatible for the
+foreseeable future. See "R6RS Incompatibilities" in the manual, for more
+information.
+
+Please contact bug-guile@gnu.org if you have found an issue not
+mentioned in that compatibility list.
+
+** New implementation of `primitive-eval'
+
+Guile's `primitive-eval' is now implemented in Scheme. Actually there is
+still a C evaluator, used when building a fresh Guile to interpret the
+compiler, so we can compile eval.scm. Thereafter all calls to
+primitive-eval are implemented by VM-compiled code.
+
+This allows all of Guile's procedures, be they interpreted or compiled,
+to execute on the same stack, unifying multiple-value return semantics,
+providing for proper tail recursion between interpreted and compiled
+code, and simplifying debugging.
+
+As part of this change, the evaluator no longer mutates the internal
+representation of the code being evaluated in a thread-unsafe manner.
+
+There are two negative aspects of this change, however. First, Guile
+takes a lot longer to compile now. Also, there is less debugging
+information available for debugging interpreted code. We hope to improve
+both of these situations.
+
+There are many changes to the internal C evalator interface, but all
+public interfaces should be the same. See the ChangeLog for details. If
+we have inadvertantly changed an interface that you were using, please
+contact bug-guile@gnu.org.
+
+** Procedure removed: `the-environment'
+
+This procedure was part of the interpreter's execution model, and does
+not apply to the compiler.
+
+** No more `local-eval'
+
+`local-eval' used to exist so that one could evaluate code in the
+lexical context of a function. Since there is no way to get the lexical
+environment any more, as that concept has no meaning for the compiler,
+and a different meaning for the interpreter, we have removed the
+function.
+
+If you think you need `local-eval', you should probably implement your
+own metacircular evaluator. It will probably be as fast as Guile's
+anyway.
+
+** Scheme source files will now be compiled automatically.
+
+If a compiled .go file corresponding to a .scm file is not found or is
+not fresh, the .scm file will be compiled on the fly, and the resulting
+.go file stored away. An advisory note will be printed on the console.
+
+Note that this mechanism depends on the timestamp of the .go file being
+newer than that of the .scm file; if the .scm or .go files are moved
+after installation, care should be taken to preserve their original
+timestamps.
+
+Auto-compiled files will be stored in the $XDG_CACHE_HOME/guile/ccache
+directory, where $XDG_CACHE_HOME defaults to ~/.cache. This directory
+will be created if needed.
+
+To inhibit automatic compilation, set the GUILE_AUTO_COMPILE environment
+variable to 0, or pass --no-auto-compile on the Guile command line.
+
+** New POSIX procedures: `getrlimit' and `setrlimit'
+
+Note however that the interface of these functions is likely to change
+in the next prerelease.
+
+** New POSIX procedure: `getsid'
+
+Scheme binding for the `getsid' C library call.
+
+** New POSIX procedure: `getaddrinfo'
+
+Scheme binding for the `getaddrinfo' C library function.
+
+** Multicast socket options
+
+Support was added for the IP_MULTICAST_TTL and IP_MULTICAST_IF socket
+options. See "Network Sockets and Communication" in the manual, for
+more information.
+
+** `recv!', `recvfrom!', `send', `sendto' now deal in bytevectors
+
+These socket procedures now take bytevectors as arguments, instead of
+strings. There is some deprecated string support, however.
+
+** New GNU procedures: `setaffinity' and `getaffinity'.
+
+See "Processes" in the manual, for more information.
+
+** New procedures: `compose', `negate', and `const'
+
+See "Higher-Order Functions" in the manual, for more information.
+
+** New procedure in `(oops goops)': `method-formals'
+
+** New procedures in (ice-9 session): `add-value-help-handler!',
+ `remove-value-help-handler!', `add-name-help-handler!'
+ `remove-name-help-handler!', `procedure-arguments'
+
+The value and name help handlers provide some minimal extensibility to
+the help interface. Guile-lib's `(texinfo reflection)' uses them, for
+example, to make stexinfo help documentation available. See those
+procedures' docstrings for more information.
+
+`procedure-arguments' describes the arguments that a procedure can take,
+combining arity and formals. For example:
+
+ (procedure-arguments resolve-interface)
+ => ((required . (name)) (rest . args))
+
+Additionally, `module-commentary' is now publically exported from
+`(ice-9 session).
+
+** Removed: `procedure->memoizing-macro', `procedure->syntax'
+
+These procedures created primitive fexprs for the old evaluator, and are
+no longer supported. If you feel that you need these functions, you
+probably need to write your own metacircular evaluator (which will
+probably be as fast as Guile's, anyway).
+
+** New language: ECMAScript
+
+Guile now ships with one other high-level language supported,
+ECMAScript. The goal is to support all of version 3.1 of the standard,
+but not all of the libraries are there yet. This support is not yet
+documented; ask on the mailing list if you are interested.
+
+** New language: Brainfuck
+
+Brainfuck is a toy language that closely models Turing machines. Guile's
+brainfuck compiler is meant to be an example of implementing other
+languages. See the manual for details, or
+http://en.wikipedia.org/wiki/Brainfuck for more information about the
+Brainfuck language itself.
+
+** New language: Elisp
+
+Guile now has an experimental Emacs Lisp compiler and runtime. You can
+now switch to Elisp at the repl: `,language elisp'. All kudos to Daniel
+Kraft and Brian Templeton, and all bugs to bug-guile@gnu.org.
+
+** Better documentation infrastructure for macros
+
+It is now possible to introspect on the type of a macro, e.g.
+syntax-rules, identifier-syntax, etc, and extract information about that
+macro, such as the syntax-rules patterns or the defmacro arguments.
+`(texinfo reflection)' takes advantage of this to give better macro
+documentation.
+
+** Support for arbitrary procedure metadata
+
+Building on its support for docstrings, Guile now supports multiple
+docstrings, adding them to the tail of a compiled procedure's
+properties. For example:
+
+ (define (foo)
+ "one"
+ "two"
+ 3)
+ (procedure-properties foo)
+ => ((name . foo) (documentation . "one") (documentation . "two"))
+
+Also, vectors of pairs are now treated as additional metadata entries:
+
+ (define (bar)
+ #((quz . #f) (docstring . "xyzzy"))
+ 3)
+ (procedure-properties bar)
+ => ((name . bar) (quz . #f) (docstring . "xyzzy"))
+
+This allows arbitrary literals to be embedded as metadata in a compiled
+procedure.
+
+** The psyntax expander now knows how to interpret the @ and @@ special
+ forms.
+
+** The psyntax expander is now hygienic with respect to modules.
+
+Free variables in a macro are scoped in the module that the macro was
+defined in, not in the module the macro is used in. For example, code
+like this works now:
+
+ (define-module (foo) #:export (bar))
+ (define (helper x) ...)
+ (define-syntax bar
+ (syntax-rules () ((_ x) (helper x))))
+
+ (define-module (baz) #:use-module (foo))
+ (bar qux)
+
+It used to be you had to export `helper' from `(foo)' as well.
+Thankfully, this has been fixed.
+
+** Support for version information in Guile's `module' form
+
+Guile modules now have a `#:version' field. See "R6RS Version
+References", "General Information about Modules", "Using Guile Modules",
+and "Creating Guile Modules" in the manual for more information.
+
+** Support for renaming bindings on module export
+
+Wherever Guile accepts a symbol as an argument to specify a binding to
+export, it now also accepts a pair of symbols, indicating that a binding
+should be renamed on export. See "Creating Guile Modules" in the manual
+for more information.
+
+** New procedure: `module-export-all!'
+
+This procedure exports all current and future bindings from a module.
+Use as `(module-export-all! (current-module))'.
+
+** New procedure `reload-module', and `,reload' REPL command
+
+See "Module System Reflection" and "Module Commands" in the manual, for
+more information.
+
+** `eval-case' has been deprecated, and replaced by `eval-when'.
+
+The semantics of `eval-when' are easier to understand. See "Eval When"
+in the manual, for more information.
+
+** Guile is now more strict about prohibiting definitions in expression
+ contexts.
+
+Although previous versions of Guile accepted it, the following
+expression is not valid, in R5RS or R6RS:
+
+ (if test (define foo 'bar) (define foo 'baz))
+
+In this specific case, it would be better to do:
+
+ (define foo (if test 'bar 'baz))
+
+It is possible to circumvent this restriction with e.g.
+`(module-define! (current-module) 'foo 'baz)'. Contact the list if you
+have any questions.
+
+** Support for `letrec*'
+
+Guile now supports `letrec*', a recursive lexical binding operator in
+which the identifiers are bound in order. See "Local Bindings" in the
+manual, for more details.
+
+** Internal definitions now expand to `letrec*'
+
+Following the R6RS, internal definitions now expand to letrec* instead
+of letrec. The following program is invalid for R5RS, but valid for
+R6RS:
+
+ (define (foo)
+ (define bar 10)
+ (define baz (+ bar 20))
+ baz)
+
+ ;; R5RS and Guile <= 1.8:
+ (foo) => Unbound variable: bar
+ ;; R6RS and Guile >= 2.0:
+ (foo) => 30
+
+This change should not affect correct R5RS programs, or programs written
+in earlier Guile dialects.
+
+** Macro expansion produces structures instead of s-expressions
+
+In the olden days, macroexpanding an s-expression would yield another
+s-expression. Though the lexical variables were renamed, expansions of
+core forms like `if' and `begin' were still non-hygienic, as they relied
+on the toplevel definitions of `if' et al being the conventional ones.
+
+The solution is to expand to structures instead of s-expressions. There
+is an `if' structure, a `begin' structure, a `toplevel-ref' structure,
+etc. The expander already did this for compilation, producing Tree-IL
+directly; it has been changed now to do so when expanding for the
+evaluator as well.
+
+** Defmacros must now produce valid Scheme expressions.
+
+It used to be that defmacros could unquote in Scheme values, as a way of
+supporting partial evaluation, and avoiding some hygiene issues. For
+example:
+
+ (define (helper x) ...)
+ (define-macro (foo bar)
+ `(,helper ,bar))
+
+Assuming this macro is in the `(baz)' module, the direct translation of
+this code would be:
+
+ (define (helper x) ...)
+ (define-macro (foo bar)
+ `((@@ (baz) helper) ,bar))
+
+Of course, one could just use a hygienic macro instead:
+
+ (define-syntax foo
+ (syntax-rules ()
+ ((_ bar) (helper bar))))
+
+** Guile's psyntax now supports docstrings and internal definitions.
+
+The following Scheme is not strictly legal:
+
+ (define (foo)
+ "bar"
+ (define (baz) ...)
+ (baz))
+
+However its intent is fairly clear. Guile interprets "bar" to be the
+docstring of `foo', and the definition of `baz' is still in definition
+context.
+
+** Support for settable identifier syntax
+
+Following the R6RS, "variable transformers" are settable
+identifier-syntax. See "Identifier macros" in the manual, for more
+information.
+
+** syntax-case treats `_' as a placeholder
+
+Following R6RS, a `_' in a syntax-rules or syntax-case pattern matches
+anything, and binds no pattern variables. Unlike the R6RS, Guile also
+permits `_' to be in the literals list for a pattern.
+
+** Macros need to be defined before their first use.
+
+It used to be that with lazy memoization, this might work:
+
+ (define (foo x)
+ (ref x))
+ (define-macro (ref x) x)
+ (foo 1) => 1
+
+But now, the body of `foo' is interpreted to mean a call to the toplevel
+`ref' function, instead of a macro expansion. The solution is to define
+macros before code that uses them.
+
+** Functions needed by macros at expand-time need to be present at
+ expand-time.
+
+For example, this code will work at the REPL:
+
+ (define (double-helper x) (* x x))
+ (define-macro (double-literal x) (double-helper x))
+ (double-literal 2) => 4
+
+But it will not work when a file is compiled, because the definition of
+`double-helper' is not present at expand-time. The solution is to wrap
+the definition of `double-helper' in `eval-when':
+
+ (eval-when (load compile eval)
+ (define (double-helper x) (* x x)))
+ (define-macro (double-literal x) (double-helper x))
+ (double-literal 2) => 4
+
+See the documentation for eval-when for more information.
+
+** `macroexpand' produces structures, not S-expressions.
+
+Given the need to maintain referential transparency, both lexically and
+modular, the result of expanding Scheme expressions is no longer itself
+an s-expression. If you want a human-readable approximation of the
+result of `macroexpand', call `tree-il->scheme' from `(language
+tree-il)'.
+
+** Removed function: `macroexpand-1'
+
+It is unclear how to implement `macroexpand-1' with syntax-case, though
+PLT Scheme does prove that it is possible.
+
+** New reader macros: #' #` #, #,@
+
+These macros translate, respectively, to `syntax', `quasisyntax',
+`unsyntax', and `unsyntax-splicing'. See the R6RS for more information.
+These reader macros may be overridden by `read-hash-extend'.
+
+** Incompatible change to #'
+
+Guile did have a #' hash-extension, by default, which just returned the
+subsequent datum: #'foo => foo. In the unlikely event that anyone
+actually used this, this behavior may be reinstated via the
+`read-hash-extend' mechanism.
+
+** `unquote' and `unquote-splicing' accept multiple expressions
+
+As per the R6RS, these syntax operators can now accept any number of
+expressions to unquote.
+
+** Scheme expresssions may be commented out with #;
+
+#; comments out an entire expression. See SRFI-62 or the R6RS for more
+information.
+
+** Prompts: Delimited, composable continuations
+
+Guile now has prompts as part of its primitive language. See "Prompts"
+in the manual, for more information.
+
+Expressions entered in at the REPL, or from the command line, are
+surrounded by a prompt with the default prompt tag.
+
+** `make-stack' with a tail-called procedural narrowing argument no longer
+ works (with compiled procedures)
+
+It used to be the case that a captured stack could be narrowed to select
+calls only up to or from a certain procedure, even if that procedure
+already tail-called another procedure. This was because the debug
+information from the original procedure was kept on the stack.
+
+Now with the new compiler, the stack only contains active frames from
+the current continuation. A narrow to a procedure that is not in the
+stack will result in an empty stack. To fix this, narrow to a procedure
+that is active in the current continuation, or narrow to a specific
+number of stack frames.
+
+** Backtraces through compiled procedures only show procedures that are
+ active in the current continuation
+
+Similarly to the previous issue, backtraces in compiled code may be
+different from backtraces in interpreted code. There are no semantic
+differences, however. Please mail bug-guile@gnu.org if you see any
+deficiencies with Guile's backtraces.
+
+** `positions' reader option enabled by default
+
+This change allows primitive-load without --auto-compile to also
+propagate source information through the expander, for better errors and
+to let macros know their source locations. The compiler was already
+turning it on anyway.
+
+** New macro: `current-source-location'
+
+The macro returns the current source location (to be documented).
+
+** syntax-rules and syntax-case macros now propagate source information
+ through to the expanded code
+
+This should result in better backtraces.
+
+** The currying behavior of `define' has been removed.
+
+Before, `(define ((f a) b) (* a b))' would translate to
+
+ (define f (lambda (a) (lambda (b) (* a b))))
+
+Now a syntax error is signaled, as this syntax is not supported by
+default. Use the `(ice-9 curried-definitions)' module to get back the
+old behavior.
+
+** New procedure, `define!'
+
+`define!' is a procedure that takes two arguments, a symbol and a value,
+and binds the value to the symbol in the current module. It's useful to
+programmatically make definitions in the current module, and is slightly
+less verbose than `module-define!'.
+
+** All modules have names now
+
+Before, you could have anonymous modules: modules without names. Now,
+because of hygiene and macros, all modules have names. If a module was
+created without a name, the first time `module-name' is called on it, a
+fresh name will be lazily generated for it.
+
+** The module namespace is now separate from the value namespace
+
+It was a little-known implementation detail of Guile's module system
+that it was built on a single hierarchical namespace of values -- that
+if there was a module named `(foo bar)', then in the module named
+`(foo)' there was a binding from `bar' to the `(foo bar)' module.
+
+This was a neat trick, but presented a number of problems. One problem
+was that the bindings in a module were not apparent from the module
+itself; perhaps the `(foo)' module had a private binding for `bar', and
+then an external contributor defined `(foo bar)'. In the end there can
+be only one binding, so one of the two will see the wrong thing, and
+produce an obtuse error of unclear provenance.
+
+Also, the public interface of a module was also bound in the value
+namespace, as `%module-public-interface'. This was a hack from the early
+days of Guile's modules.
+
+Both of these warts have been fixed by the addition of fields in the
+`module' data type. Access to modules and their interfaces from the
+value namespace has been deprecated, and all accessors use the new
+record accessors appropriately.
+
+When Guile is built with support for deprecated code, as is the default,
+the value namespace is still searched for modules and public interfaces,
+and a deprecation warning is raised as appropriate.
+
+Finally, to support lazy loading of modules as one used to be able to do
+with module binder procedures, Guile now has submodule binders, called
+if a given submodule is not found. See boot-9.scm for more information.
+
+** New procedures: module-ref-submodule, module-define-submodule,
+ nested-ref-module, nested-define-module!, local-ref-module,
+ local-define-module
+
+These new accessors are like their bare variants, but operate on
+namespaces instead of values.
+
+** The (app modules) module tree is officially deprecated
+
+It used to be that one could access a module named `(foo bar)' via
+`(nested-ref the-root-module '(app modules foo bar))'. The `(app
+modules)' bit was a never-used and never-documented abstraction, and has
+been deprecated. See the following mail for a full discussion:
+
+ http://lists.gnu.org/archive/html/guile-devel/2010-04/msg00168.html
+
+The `%app' binding is also deprecated.
+
+** `module-filename' field and accessor
+
+Modules now record the file in which they are defined. This field may be
+accessed with the new `module-filename' procedure.
+
+** Modules load within a known environment
+
+It takes a few procedure calls to define a module, and those procedure
+calls need to be in scope. Now we ensure that the current module when
+loading a module is one that has the needed bindings, instead of relying
+on chance.
+
+** `load' is a macro (!) that resolves paths relative to source file dir
+
+The familiar Schem `load' procedure is now a macro that captures the
+name of the source file being expanded, and dispatches to the new
+`load-in-vicinity'. Referencing `load' by bare name returns a closure
+that embeds the current source file name.
+
+This fix allows `load' of relative paths to be resolved with respect to
+the location of the file that calls `load'.
+
+** Many syntax errors have different texts now
+
+Syntax errors still throw to the `syntax-error' key, but the arguments
+are often different now. Perhaps in the future, Guile will switch to
+using standard SRFI-35 conditions.
+
+** Returning multiple values to compiled code will silently truncate the
+ values to the expected number
+
+For example, the interpreter would raise an error evaluating the form,
+`(+ (values 1 2) (values 3 4))', because it would see the operands as
+being two compound "values" objects, to which `+' does not apply.
+
+The compiler, on the other hand, receives multiple values on the stack,
+not as a compound object. Given that it must check the number of values
+anyway, if too many values are provided for a continuation, it chooses
+to truncate those values, effectively evaluating `(+ 1 3)' instead.
+
+The idea is that the semantics that the compiler implements is more
+intuitive, and the use of the interpreter will fade out with time.
+This behavior is allowed both by the R5RS and the R6RS.
+
+** Multiple values in compiled code are not represented by compound
+ objects
+
+This change may manifest itself in the following situation:
+
+ (let ((val (foo))) (do-something) val)
+
+In the interpreter, if `foo' returns multiple values, multiple values
+are produced from the `let' expression. In the compiler, those values
+are truncated to the first value, and that first value is returned. In
+the compiler, if `foo' returns no values, an error will be raised, while
+the interpreter would proceed.
+
+Both of these behaviors are allowed by R5RS and R6RS. The compiler's
+behavior is more correct, however. If you wish to preserve a potentially
+multiply-valued return, you will need to set up a multiple-value
+continuation, using `call-with-values'.
+
+** Defmacros are now implemented in terms of syntax-case.
+
+The practical ramification of this is that the `defmacro?' predicate has
+been removed, along with `defmacro-transformer', `macro-table',
+`xformer-table', `assert-defmacro?!', `set-defmacro-transformer!' and
+`defmacro:transformer'. This is because defmacros are simply macros. If
+any of these procedures provided useful facilities to you, we encourage
+you to contact the Guile developers.
+
+** Hygienic macros documented as the primary syntactic extension mechanism.
+
+The macro documentation was finally fleshed out with some documentation
+on `syntax-rules' and `syntax-case' macros, and other parts of the macro
+expansion process. See "Macros" in the manual, for details.
+
+** psyntax is now the default expander
+
+Scheme code is now expanded by default by the psyntax hygienic macro
+expander. Expansion is performed completely before compilation or
+interpretation.
+
+Notably, syntax errors will be signalled before interpretation begins.
+In the past, many syntax errors were only detected at runtime if the
+code in question was memoized.
+
+As part of its expansion, psyntax renames all lexically-bound
+identifiers. Original identifier names are preserved and given to the
+compiler, but the interpreter will see the renamed variables, e.g.,
+`x432' instead of `x'.
+
+Note that the psyntax that Guile uses is a fork, as Guile already had
+modules before incompatible modules were added to psyntax -- about 10
+years ago! Thus there are surely a number of bugs that have been fixed
+in psyntax since then. If you find one, please notify bug-guile@gnu.org.
+
+** syntax-rules and syntax-case are available by default.
+
+There is no longer any need to import the `(ice-9 syncase)' module
+(which is now deprecated). The expander may be invoked directly via
+`macroexpand', though it is normally searched for via the current module
+transformer.
+
+Also, the helper routines for syntax-case are available in the default
+environment as well: `syntax->datum', `datum->syntax',
+`bound-identifier=?', `free-identifier=?', `generate-temporaries',
+`identifier?', and `syntax-violation'. See the R6RS for documentation.
+
+** Tail patterns in syntax-case
+
+Guile has pulled in some more recent changes from the psyntax portable
+syntax expander, to implement support for "tail patterns". Such patterns
+are supported by syntax-rules and syntax-case. This allows a syntax-case
+match clause to have ellipses, then a pattern at the end. For example:
+
+ (define-syntax case
+ (syntax-rules (else)
+ ((_ val match-clause ... (else e e* ...))
+ [...])))
+
+Note how there is MATCH-CLAUSE, which is ellipsized, then there is a
+tail pattern for the else clause. Thanks to Andreas Rottmann for the
+patch, and Kent Dybvig for the code.
+
+** Lexical bindings introduced by hygienic macros may not be referenced
+ by nonhygienic macros.
+
+If a lexical binding is introduced by a hygienic macro, it may not be
+referenced by a nonhygienic macro. For example, this works:
+
+ (let ()
+ (define-macro (bind-x val body)
+ `(let ((x ,val)) ,body))
+ (define-macro (ref x)
+ x)
+ (bind-x 10 (ref x)))
+
+But this does not:
+
+ (let ()
+ (define-syntax bind-x
+ (syntax-rules ()
+ ((_ val body) (let ((x val)) body))))
+ (define-macro (ref x)
+ x)
+ (bind-x 10 (ref x)))
+
+It is not normal to run into this situation with existing code. However,
+if you have defmacros that expand to hygienic macros, it is possible to
+run into situations like this. For example, if you have a defmacro that
+generates a `while' expression, the `break' bound by the `while' may not
+be visible within other parts of your defmacro. The solution is to port
+from defmacros to syntax-rules or syntax-case.
+
+** Macros may no longer be referenced as first-class values.
+
+In the past, you could evaluate e.g. `if', and get its macro value. Now,
+expanding this form raises a syntax error.
+
+Macros still /exist/ as first-class values, but they must be
+/referenced/ via the module system, e.g. `(module-ref (current-module)
+'if)'.
+
+** Macros may now have docstrings.
+
+`object-documentation' from `(ice-9 documentation)' may be used to
+retrieve the docstring, once you have a macro value -- but see the above
+note about first-class macros. Docstrings are associated with the syntax
+transformer procedures.
+
+** `case-lambda' is now available in the default environment.
+
+The binding in the default environment is equivalent to the one from the
+`(srfi srfi-16)' module. Use the srfi-16 module explicitly if you wish
+to maintain compatibility with Guile 1.8 and earlier.
+
+** Procedures may now have more than one arity.
+
+This can be the case, for example, in case-lambda procedures. The
+arities of compiled procedures may be accessed via procedures from the
+`(system vm program)' module; see "Compiled Procedures", "Optional
+Arguments", and "Case-lambda" in the manual.
+
+** Deprecate arity access via (procedure-properties proc 'arity)
+
+Instead of accessing a procedure's arity as a property, use the new
+`procedure-minimum-arity' function, which gives the most permissive
+arity that the the function has, in the same format as the old arity
+accessor.
+
+** `lambda*' and `define*' are now available in the default environment
+
+As with `case-lambda', `(ice-9 optargs)' continues to be supported, for
+compatibility purposes. No semantic change has been made (we hope).
+Optional and keyword arguments now dispatch via special VM operations,
+without the need to cons rest arguments, making them very fast.
+
+** New syntax: define-once
+
+`define-once' is like Lisp's `defvar': it creates a toplevel binding,
+but only if one does not exist already.
+
+** New function, `truncated-print', with `format' support
+
+`(ice-9 pretty-print)' now exports `truncated-print', a printer that
+will ensure that the output stays within a certain width, truncating the
+output in what is hopefully an intelligent manner. See the manual for
+more details.
+
+There is a new `format' specifier, `~@y', for doing a truncated
+print (as opposed to `~y', which does a pretty-print). See the `format'
+documentation for more details.
+
+** Better pretty-printing
+
+Indentation recognizes more special forms, like `syntax-case', and read
+macros like `quote' are printed better.
+
+** Passing a number as the destination of `format' is deprecated
+
+The `format' procedure in `(ice-9 format)' now emits a deprecation
+warning if a number is passed as its first argument.
+
+Also, it used to be that you could omit passing a port to `format', in
+some cases. This still works, but has been formally deprecated.
+
+** SRFI-4 vectors reimplemented in terms of R6RS bytevectors
+
+Guile now implements SRFI-4 vectors using bytevectors. Often when you
+have a numeric vector, you end up wanting to write its bytes somewhere,
+or have access to the underlying bytes, or read in bytes from somewhere
+else. Bytevectors are very good at this sort of thing. But the SRFI-4
+APIs are nicer to use when doing number-crunching, because they are
+addressed by element and not by byte.
+
+So as a compromise, Guile allows all bytevector functions to operate on
+numeric vectors. They address the underlying bytes in the native
+endianness, as one would expect.
+
+Following the same reasoning, that it's just bytes underneath, Guile
+also allows uniform vectors of a given type to be accessed as if they
+were of any type. One can fill a u32vector, and access its elements with
+u8vector-ref. One can use f64vector-ref on bytevectors. It's all the
+same to Guile.
+
+In this way, uniform numeric vectors may be written to and read from
+input/output ports using the procedures that operate on bytevectors.
+
+Calls to SRFI-4 accessors (ref and set functions) from Scheme are now
+inlined to the VM instructions for bytevector access.
+
+See "SRFI-4" in the manual, for more information.
+
+** Nonstandard SRFI-4 procedures now available from `(srfi srfi-4 gnu)'
+
+Guile's `(srfi srfi-4)' now only exports those srfi-4 procedures that
+are part of the standard. Complex uniform vectors and the
+`any->FOOvector' family are now available only from `(srfi srfi-4 gnu)'.
+
+Guile's default environment imports `(srfi srfi-4)', and probably should
+import `(srfi srfi-4 gnu)' as well.
+
+See "SRFI-4 Extensions" in the manual, for more information.
+
+** New syntax: include-from-path.
+
+`include-from-path' is like `include', except it looks for its file in
+the load path. It can be used to compile other files into a file.
+
+** New syntax: quasisyntax.
+
+`quasisyntax' is to `syntax' as `quasiquote' is to `quote'. See the R6RS
+documentation for more information. Thanks to Andre van Tonder for the
+implementation.
+
+** `*unspecified*' is identifier syntax
+
+`*unspecified*' is no longer a variable, so it is optimized properly by
+the compiler, and is not `set!'-able.
+
+** Changes and bugfixes in numerics code
+
+*** Added six new sets of fast quotient and remainder operators
+
+Added six new sets of fast quotient and remainder operator pairs with
+different semantics than the R5RS operators. They support not only
+integers, but all reals, including exact rationals and inexact
+floating point numbers.
+
+These procedures accept two real numbers N and D, where the divisor D
+must be non-zero. Each set of operators computes an integer quotient
+Q and a real remainder R such that N = Q*D + R and |R| < |D|. They
+differ only in how N/D is rounded to produce Q.
+
+`euclidean-quotient' returns the integer Q and `euclidean-remainder'
+returns the real R such that N = Q*D + R and 0 <= R < |D|. `euclidean/'
+returns both Q and R, and is more efficient than computing each
+separately. Note that when D > 0, `euclidean-quotient' returns
+floor(N/D), and when D < 0 it returns ceiling(N/D).
+
+`centered-quotient', `centered-remainder', and `centered/' are similar
+except that the range of remainders is -abs(D/2) <= R < abs(D/2), and
+`centered-quotient' rounds N/D to the nearest integer. Note that these
+operators are equivalent to the R6RS integer division operators `div',
+`mod', `div-and-mod', `div0', `mod0', and `div0-and-mod0'.
+
+`floor-quotient' and `floor-remainder' compute Q and R, respectively,
+where Q has been rounded toward negative infinity. `floor/' returns
+both Q and R, and is more efficient than computing each separately.
+Note that when applied to integers, `floor-remainder' is equivalent to
+the R5RS integer-only `modulo' operator. `ceiling-quotient',
+`ceiling-remainder', and `ceiling/' are similar except that Q is
+rounded toward positive infinity.
+
+For `truncate-quotient', `truncate-remainder', and `truncate/', Q is
+rounded toward zero. Note that when applied to integers,
+`truncate-quotient' and `truncate-remainder' are equivalent to the
+R5RS integer-only operators `quotient' and `remainder'.
+
+For `round-quotient', `round-remainder', and `round/', Q is rounded to
+the nearest integer, with ties going to the nearest even integer.
+
+*** Complex number changes
+
+Guile is now able to represent non-real complex numbers whose
+imaginary part is an _inexact_ zero (0.0 or -0.0), per R6RS.
+Previously, such numbers were immediately changed into inexact reals.
+
+(real? 0.0+0.0i) now returns #f, per R6RS, although (zero? 0.0+0.0i)
+still returns #t, per R6RS. (= 0 0.0+0.0i) and (= 0.0 0.0+0.0i) are
+#t, but the same comparisons using `eqv?' or `equal?' are #f.
+
+Like other non-real numbers, these complex numbers with inexact zero
+imaginary part will raise exceptions is passed to procedures requiring
+reals, such as `<', `>', `<=', `>=', `min', `max', `positive?',
+`negative?', `inf?', `nan?', `finite?', etc.
+
+**** `make-rectangular' changes
+
+scm_make_rectangular `make-rectangular' now returns a real number only
+if the imaginary part is an _exact_ 0. Previously, it would return a
+real number if the imaginary part was an inexact zero.
+
+scm_c_make_rectangular now always returns a non-real complex number,
+even if the imaginary part is zero. Previously, it would return a
+real number if the imaginary part was zero.
+
+**** `make-polar' changes
+
+scm_make_polar `make-polar' now returns a real number only if the
+angle or magnitude is an _exact_ 0. If the magnitude is an exact 0,
+it now returns an exact 0. Previously, it would return a real
+number if the imaginary part was an inexact zero.
+
+scm_c_make_polar now always returns a non-real complex number, even if
+the imaginary part is 0.0. Previously, it would return a real number
+if the imaginary part was 0.0.
+
+**** `imag-part' changes
+
+scm_imag_part `imag-part' now returns an exact 0 if applied to an
+inexact real number. Previously it returned an inexact zero in this
+case.
+
+*** `eqv?' and `equal?' now compare numbers equivalently
+
+scm_equal_p `equal?' now behaves equivalently to scm_eqv_p `eqv?' for
+numeric values, per R5RS. Previously, equal? worked differently,
+e.g. `(equal? 0.0 -0.0)' returned #t but `(eqv? 0.0 -0.0)' returned #f,
+and `(equal? +nan.0 +nan.0)' returned #f but `(eqv? +nan.0 +nan.0)'
+returned #t.
+
+*** `(equal? +nan.0 +nan.0)' now returns #t
+
+Previously, `(equal? +nan.0 +nan.0)' returned #f, although
+`(let ((x +nan.0)) (equal? x x))' and `(eqv? +nan.0 +nan.0)'
+both returned #t. R5RS requires that `equal?' behave like
+`eqv?' when comparing numbers.
+
+*** Change in handling products `*' involving exact 0
+
+scm_product `*' now handles exact 0 differently. A product containing
+an exact 0 now returns an exact 0 if and only if the other arguments
+are all exact. An inexact zero is returned if and only if the other
+arguments are all finite but not all exact. If an infinite or NaN
+value is present, a NaN value is returned. Previously, any product
+containing an exact 0 yielded an exact 0, regardless of the other
+arguments.
+
+*** `expt' and `integer-expt' changes when the base is 0
+
+While `(expt 0 0)' is still 1, and `(expt 0 N)' for N > 0 is still
+zero, `(expt 0 N)' for N < 0 is now a NaN value, and likewise for
+integer-expt. This is more correct, and conforming to R6RS, but seems
+to be incompatible with R5RS, which would return 0 for all non-zero
+values of N.
+
+*** `expt' and `integer-expt' are more generic, less strict
+
+When raising to an exact non-negative integer exponent, `expt' and
+`integer-expt' are now able to exponentiate any object that can be
+multiplied using `*'. They can also raise an object to an exact
+negative integer power if its reciprocal can be taken using `/'.
+In order to allow this, the type of the first argument is no longer
+checked when raising to an exact integer power. If the exponent is 0
+or 1, the first parameter is not manipulated at all, and need not
+even support multiplication.
+
+*** Infinities are no longer integers, nor rationals
+
+scm_integer_p `integer?' and scm_rational_p `rational?' now return #f
+for infinities, per R6RS. Previously they returned #t for real
+infinities. The real infinities and NaNs are still considered real by
+scm_real `real?' however, per R6RS.
+
+*** NaNs are no longer rationals
+
+scm_rational_p `rational?' now returns #f for NaN values, per R6RS.
+Previously it returned #t for real NaN values. They are still
+considered real by scm_real `real?' however, per R6RS.
+
+*** `inf?' and `nan?' now throw exceptions for non-reals
+
+The domain of `inf?' and `nan?' is the real numbers. Guile now signals
+an error when a non-real number or non-number is passed to these
+procedures. (Note that NaNs _are_ considered numbers by scheme, despite
+their name).
+
+*** `rationalize' bugfixes and changes
+
+Fixed bugs in scm_rationalize `rationalize'. Previously, it returned
+exact integers unmodified, although that was incorrect if the epsilon
+was at least 1 or inexact, e.g. (rationalize 4 1) should return 3 per
+R5RS and R6RS, but previously it returned 4. It also now handles
+cases involving infinities and NaNs properly, per R6RS.
+
+*** Trigonometric functions now return exact numbers in some cases
+
+scm_sin `sin', scm_cos `cos', scm_tan `tan', scm_asin `asin', scm_acos
+`acos', scm_atan `atan', scm_sinh `sinh', scm_cosh `cosh', scm_tanh
+`tanh', scm_sys_asinh `asinh', scm_sys_acosh `acosh', and
+scm_sys_atanh `atanh' now return exact results in some cases.
+
+*** New procedure: `finite?'
+
+Add scm_finite_p `finite?' from R6RS to guile core, which returns #t
+if and only if its argument is neither infinite nor a NaN. Note that
+this is not the same as (not (inf? x)) or (not (infinite? x)), since
+NaNs are neither finite nor infinite.
+
+*** Improved exactness handling for complex number parsing
+
+When parsing non-real complex numbers, exactness specifiers are now
+applied to each component, as is done in PLT Scheme. For complex
+numbers written in rectangular form, exactness specifiers are applied
+to the real and imaginary parts before calling scm_make_rectangular.
+For complex numbers written in polar form, exactness specifiers are
+applied to the magnitude and angle before calling scm_make_polar.
+
+Previously, exactness specifiers were applied to the number as a whole
+_after_ calling scm_make_rectangular or scm_make_polar.
-* New modules (see the manual for details)
+For example, (string->number "#i5.0+0i") now does the equivalent of:
-** The `(ice-9 i18n)' module provides internationalization support
+ (make-rectangular (exact->inexact 5.0) (exact->inexact 0))
-* Changes to the distribution
+which yields 5.0+0.0i. Previously it did the equivalent of:
-** Guile now uses Gnulib as a portability aid
+ (exact->inexact (make-rectangular 5.0 0))
-* Changes to the stand-alone interpreter
-* Changes to Scheme functions and syntax
+which yielded 5.0.
+
+** Unicode characters
+
+Unicode characters may be entered in octal format via e.g. `#\454', or
+created via (integer->char 300). A hex external representation will
+probably be introduced at some point.
+
+** Unicode strings
+
+Internally, strings are now represented either in the `latin-1'
+encoding, one byte per character, or in UTF-32, with four bytes per
+character. Strings manage their own allocation, switching if needed.
+
+Extended characters may be written in a literal string using the
+hexadecimal escapes `\xXX', `\uXXXX', or `\UXXXXXX', for 8-bit, 16-bit,
+or 24-bit codepoints, respectively, or entered directly in the native
+encoding of the port on which the string is read.
+
+** Unicode symbols
+
+One may now use U+03BB (GREEK SMALL LETTER LAMBDA) as an identifier.
+
+** Support for non-ASCII source code files
+
+The default reader now handles source code files for some of the
+non-ASCII character encodings, such as UTF-8. A non-ASCII source file
+should have an encoding declaration near the top of the file. Also,
+there is a new function, `file-encoding', that scans a port for a coding
+declaration. See the section of the manual entitled, "Character Encoding
+of Source Files".
+
+The pre-1.9.3 reader handled 8-bit clean but otherwise unspecified source
+code. This use is now discouraged. Binary input and output is
+currently supported by opening ports in the ISO-8859-1 locale.
+
+** Source files default to UTF-8.
+
+If source files do not specify their encoding via a `coding:' block,
+the default encoding is UTF-8, instead of being taken from the current
+locale.
+
+** Interactive Guile installs the current locale.
+
+Instead of leaving the user in the "C" locale, running the Guile REPL
+installs the current locale. [FIXME xref?]
+
+** Support for locale transcoding when reading from and writing to ports
+
+Ports now have an associated character encoding, and port read and write
+operations do conversion to and from locales automatically. Ports also
+have an associated strategy for how to deal with locale conversion
+failures.
+
+See the documentation in the manual for the four new support functions,
+`set-port-encoding!', `port-encoding', `set-port-conversion-strategy!',
+and `port-conversion-strategy'.
+
+** String and SRFI-13 functions can operate on Unicode strings
+
+** Unicode support for SRFI-14 character sets
+
+The default character sets are no longer locale dependent and contain
+characters from the whole Unicode range. There is a new predefined
+character set, `char-set:designated', which contains all assigned
+Unicode characters. There is a new debugging function, `%char-set-dump'.
+
+** Character functions operate on Unicode characters
+
+`char-upcase' and `char-downcase' use default Unicode casing rules.
+Character comparisons such as `char<?' and `char-ci<?' now sort based on
+Unicode code points.
+
+** Global variables `scm_charnames' and `scm_charnums' are removed
+
+These variables contained the names of control characters and were
+used when writing characters. While these were global, they were
+never intended to be public API. They have been replaced with private
+functions.
+
+** EBCDIC support is removed
+
+There was an EBCDIC compile flag that altered some of the character
+processing. It appeared that full EBCDIC support was never completed
+and was unmaintained.
+
+** Compile-time warnings
+
+Guile can warn about potentially unbound free variables. Pass the
+-Wunbound-variable on the `guile-tools compile' command line, or add
+`#:warnings '(unbound-variable)' to your `compile' or `compile-file'
+invocation. Warnings are also enabled by default for expressions entered
+at the REPL.
+
+Guile can also warn when you pass the wrong number of arguments to a
+procedure, with -Warity-mismatch, or `arity-mismatch' in the
+`#:warnings' as above.
-** A new 'memoize-symbol evaluator trap has been added. This trap can
-be used for efficiently implementing a Scheme code coverage.
+Other warnings include `-Wunused-variable' and `-Wunused-toplevel', to
+warn about unused local or global (top-level) variables, and `-Wformat',
+to check for various errors related to the `format' procedure.
+
+** A new `memoize-symbol' evaluator trap has been added.
+
+This trap can be used for efficiently implementing a Scheme code
+coverage.
** Duplicate bindings among used modules are resolved lazily.
+
This slightly improves program startup times.
** New thread cancellation and thread cleanup API
+
See `cancel-thread', `set-thread-cleanup!', and `thread-cleanup'.
+** New threads are in `(guile-user)' by default, not `(guile)'
+
+It used to be that a new thread entering Guile would do so in the
+`(guile)' module, unless this was the first time Guile was initialized,
+in which case it was `(guile-user)'. This has been fixed to have all
+new threads unknown to Guile default to `(guile-user)'.
+
+** New helpers: `print-exception', `set-exception-printer!'
+
+These functions implement an extensible exception printer. Guile
+registers printers for all of the exceptions it throws. Users may add
+their own printers. There is also `scm_print_exception', for use by C
+programs. Pleasantly, this allows SRFI-35 and R6RS exceptions to be
+printed appropriately.
+
+** GOOPS dispatch in scheme
+
+As an implementation detail, GOOPS dispatch is no longer implemented by
+special evaluator bytecodes, but rather directly via a Scheme function
+associated with an applicable struct. There is some VM support for the
+underlying primitives, like `class-of'.
+
+This change will in the future allow users to customize generic function
+dispatch without incurring a performance penalty, and allow us to
+implement method combinations.
+
+** Applicable struct support
+
+One may now make structs from Scheme that may be applied as procedures.
+To do so, make a struct whose vtable is `<applicable-struct-vtable>'.
+That struct will be the vtable of your applicable structs; instances of
+that new struct are assumed to have the procedure in their first slot.
+`<applicable-struct-vtable>' is like Common Lisp's
+`funcallable-standard-class'. Likewise there is
+`<applicable-struct-with-setter-vtable>', which looks for the setter in
+the second slot. This needs to be better documented.
+
+** GOOPS cleanups.
+
+GOOPS had a number of concepts that were relevant to the days of Tcl,
+but not any more: operators and entities, mainly. These objects were
+never documented, and it is unlikely that they were ever used. Operators
+were a kind of generic specific to the Tcl support. Entities were
+replaced by applicable structs, mentioned above.
+
+** New struct slot allocation: "hidden"
+
+A hidden slot is readable and writable, but will not be initialized by a
+call to make-struct. For example in your layout you would say "ph"
+instead of "pw". Hidden slots are useful for adding new slots to a
+vtable without breaking existing invocations to make-struct.
+
+** eqv? not a generic
+
+One used to be able to extend `eqv?' as a primitive-generic, but no
+more. Because `eqv?' is in the expansion of `case' (via `memv'), which
+should be able to compile to static dispatch tables, it doesn't make
+sense to allow extensions that would subvert this optimization.
+
+** `inet-ntop' and `inet-pton' are always available.
+
+Guile now use a portable implementation of `inet_pton'/`inet_ntop', so
+there is no more need to use `inet-aton'/`inet-ntoa'. The latter
+functions are deprecated.
+
+** `getopt-long' parsing errors throw to `quit', not `misc-error'
+
+This change should inhibit backtraces on argument parsing errors.
+`getopt-long' has been modified to print out the error that it throws
+itself.
+
+** New primitive: `tmpfile'.
+
+See "File System" in the manual.
+
+** Random generator state may be serialized to a datum
+
+`random-state->datum' will serialize a random state to a datum, which
+may be written out, read back in later, and revivified using
+`datum->random-state'. See "Random" in the manual, for more details.
+
+** Fix random number generator on 64-bit platforms
+
+There was a nasty bug on 64-bit platforms in which asking for a random
+integer with a range between 2**32 and 2**64 caused a segfault. After
+many embarrassing iterations, this was fixed.
+
+** Fast bit operations.
+
+The bit-twiddling operations `ash', `logand', `logior', and `logxor' now
+have dedicated bytecodes. Guile is not just for symbolic computation,
+it's for number crunching too.
+
+** Faster SRFI-9 record access
+
+SRFI-9 records are now implemented directly on top of Guile's structs,
+and their accessors are defined in such a way that normal call-sites
+inline to special VM opcodes, while still allowing for the general case
+(e.g. passing a record accessor to `apply').
+
+** R6RS block comment support
+
+Guile now supports R6RS nested block comments. The start of a comment is
+marked with `#|', and the end with `|#'.
+
+** `guile-2' cond-expand feature
+
+To test if your code is running under Guile 2.0 (or its alpha releases),
+test for the `guile-2' cond-expand feature. Like this:
+
+ (cond-expand (guile-2 (eval-when (compile)
+ ;; This must be evaluated at compile time.
+ (fluid-set! current-reader my-reader)))
+ (guile
+ ;; Earlier versions of Guile do not have a
+ ;; separate compilation phase.
+ (fluid-set! current-reader my-reader)))
+
+** New global variables: %load-compiled-path, %load-compiled-extensions
+
+These are analogous to %load-path and %load-extensions.
+
+** New fluid: `%file-port-name-canonicalization'
+
+This fluid parameterizes the file names that are associated with file
+ports. If %file-port-name-canonicalization is 'absolute, then file names
+are canonicalized to be absolute paths. If it is 'relative, then the
+name is canonicalized, but any prefix corresponding to a member of
+`%load-path' is stripped off. Otherwise the names are passed through
+unchanged.
+
+In addition, the `compile-file' and `compile-and-load' procedures bind
+%file-port-name-canonicalization to their `#:canonicalization' keyword
+argument, which defaults to 'relative. In this way, one might compile
+"../module/ice-9/boot-9.scm", but the path that gets residualized into
+the .go is "ice-9/boot-9.scm".
+
+** New procedure, `make-promise'
+
+`(make-promise (lambda () foo))' is equivalent to `(delay foo)'.
+
+** `defined?' may accept a module as its second argument
+
+Previously it only accepted internal structures from the evaluator.
+
+** New entry into %guile-build-info: `ccachedir'
+
+** Fix bug in `module-bound?'.
+
+`module-bound?' was returning true if a module did have a local
+variable, but one that was unbound, but another imported module bound
+the variable. This was an error, and was fixed.
+
+** `(ice-9 syncase)' has been deprecated.
+
+As syntax-case is available by default, importing `(ice-9 syncase)' has
+no effect, and will trigger a deprecation warning.
+
+** New readline history functions
+
+The (ice-9 readline) module now provides add-history, read-history,
+write-history and clear-history, which wrap the corresponding GNU
+History library functions.
+
+** Removed deprecated uniform array procedures:
+ dimensions->uniform-array, list->uniform-array, array-prototype
+
+Instead, use make-typed-array, list->typed-array, or array-type,
+respectively.
+
+** Deprecate the old `scm-style-repl'
+
+The following bindings from boot-9 are now found in `(ice-9
+scm-style-repl)': `scm-style-repl', `error-catching-loop',
+`error-catching-repl', `bad-throw', `scm-repl-silent'
+`assert-repl-silence', `repl-print-unspecified',
+`assert-repl-print-unspecified', `scm-repl-verbose',
+`assert-repl-verbosity', `scm-repl-prompt', `set-repl-prompt!', `repl',
+`default-pre-unwind-handler', `handle-system-error',
+
+The following bindings have been deprecated, with no replacement:
+`pre-unwind-handler-dispatch'.
+
+The following bindings have been totally removed:
+`before-signal-stack'.
+
+Deprecated forwarding shims have been installed so that users that
+expect these bindings in the main namespace will still work, but receive
+a deprecation warning.
+
+** `set-batch-mode?!' replaced by `ensure-batch-mode!'
+
+"Batch mode" is a flag used to tell a program that it is not running
+interactively. One usually turns it on after a fork. It may not be
+turned off. `ensure-batch-mode!' deprecates the old `set-batch-mode?!',
+because it is a better interface, as it can only turn on batch mode, not
+turn it off.
+
+** Deprecate `save-stack', `the-last-stack'
+
+It used to be that the way to debug programs in Guile was to capture the
+stack at the time of error, drop back to the REPL, then debug that
+stack. But this approach didn't compose, was tricky to get right in the
+presence of threads, and was not very powerful.
+
+So `save-stack', `stack-saved?', and `the-last-stack' have been moved to
+`(ice-9 save-stack)', with deprecated bindings left in the root module.
+
+** `top-repl' has its own module
+
+The `top-repl' binding, called with Guile is run interactively, is now
+is its own module, `(ice-9 top-repl)'. A deprecated forwarding shim was
+left in the default environment.
+
+** `display-error' takes a frame
+
+The `display-error' / `scm_display_error' helper now takes a frame as an
+argument instead of a stack. Stacks are still supported in deprecated
+builds. Additionally, `display-error' will again source location
+information for the error.
+
+** No more `(ice-9 debug)'
+
+This module had some debugging helpers that are no longer applicable to
+the current debugging model. Importing this module will produce a
+deprecation warning. Users should contact bug-guile for support.
+
+** Remove obsolete debug-options
+
+Removed `breakpoints', `trace', `procnames', `indent', `frames',
+`maxdepth', and `debug' debug-options.
+
+** `backtrace' debug option on by default
+
+Given that Guile 2.0 can always give you a backtrace, backtraces are now
+on by default.
+
+** `turn-on-debugging' deprecated
+
+** Remove obsolete print-options
+
+The `source' and `closure-hook' print options are obsolete, and have
+been removed.
+
+** Remove obsolete read-options
+
+The "elisp-strings" and "elisp-vectors" read options were unused and
+obsolete, so they have been removed.
+
+** Remove eval-options and trap-options
+
+Eval-options and trap-options are obsolete with the new VM and
+evaluator.
+
+** Remove (ice-9 debugger) and (ice-9 debugging)
+
+See "Traps" and "Interactive Debugging" in the manual, for information
+on their replacements.
+
+** Remove the GDS Emacs integration
+
+See "Using Guile in Emacs" in the manual, for info on how we think you
+should use Guile with Emacs.
+
+** Deprecated: `lazy-catch'
+
+`lazy-catch' was a form that captured the stack at the point of a
+`throw', but the dynamic state at the point of the `catch'. It was a bit
+crazy. Please change to use `catch', possibly with a throw-handler, or
+`with-throw-handler'.
+
+** Deprecated: primitive properties
+
+The `primitive-make-property', `primitive-property-set!',
+`primitive-property-ref', and `primitive-property-del!' procedures were
+crufty and only used to implement object properties, which has a new,
+threadsafe implementation. Use object properties or weak hash tables
+instead.
+
+** Deprecated `@bind' syntax
+
+`@bind' was part of an older implementation of the Emacs Lisp language,
+and is no longer used.
+
+** Miscellaneous other deprecations
+
+`cuserid' has been deprecated, as it only returns 8 bytes of a user's
+login. Use `(passwd:name (getpwuid (geteuid)))' instead.
+
+Additionally, the procedures `apply-to-args', `has-suffix?', `scheme-file-suffix'
+`get-option', `for-next-option', `display-usage-report',
+`transform-usage-lambda', `collect', and `set-batch-mode?!' have all
+been deprecated.
+
+** Add support for unbound fluids
+
+See `make-unbound-fluid', `fluid-unset!', and `fluid-bound?' in the
+manual.
+
+** Add `variable-unset!'
+
+See "Variables" in the manual, for more details.
+
+** Last but not least, the `λ' macro can be used in lieu of `lambda'
+
* Changes to the C interface
+** Guile now uses libgc, the Boehm-Demers-Weiser garbage collector
+
+The semantics of `scm_gc_malloc ()' have been changed, in a
+backward-compatible way. A new allocation routine,
+`scm_gc_malloc_pointerless ()', was added.
+
+Libgc is a conservative GC, which we hope will make interaction with C
+code easier and less error-prone.
+
+** New procedures: `scm_to_stringn', `scm_from_stringn'
+** New procedures: scm_{to,from}_{utf8,latin1}_symbol{n,}
+** New procedures: scm_{to,from}_{utf8,utf32,latin1}_string{n,}
+
+These new procedures convert to and from string representations in
+particular encodings.
+
+Users should continue to use locale encoding for user input, user
+output, or interacting with the C library.
+
+Use the Latin-1 functions for ASCII, and for literals in source code.
+
+Use UTF-8 functions for interaction with modern libraries which deal in
+UTF-8, and UTF-32 for interaction with utf32-using libraries.
+
+Otherwise, use scm_to_stringn or scm_from_stringn with a specific
+encoding.
+
+** New type definitions for `scm_t_intptr' and friends.
+
+`SCM_T_UINTPTR_MAX', `SCM_T_INTPTR_MIN', `SCM_T_INTPTR_MAX',
+`SIZEOF_SCM_T_BITS', `scm_t_intptr' and `scm_t_uintptr' are now
+available to C. Have fun!
+
+** The GH interface (deprecated in version 1.6, 2001) was removed.
+
+** Internal `scm_i_' functions now have "hidden" linkage with GCC/ELF
+
+This makes these internal functions technically not callable from
+application code.
+
** Functions for handling `scm_option' now no longer require an argument
indicating length of the `scm_t_option' array.
+** Procedures-with-setters are now implemented using applicable structs
+
+From a user's perspective this doesn't mean very much. But if, for some
+odd reason, you used the SCM_PROCEDURE_WITH_SETTER_P, SCM_PROCEDURE, or
+SCM_SETTER macros, know that they're deprecated now. Also, scm_tc7_pws
+is gone.
+
+** Remove old evaluator closures
+
+There used to be ranges of typecodes allocated to interpreted data
+structures, but that it no longer the case, given that interpreted
+procedure are now just regular VM closures. As a result, there is a
+newly free tc3, and a number of removed macros. See the ChangeLog for
+details.
+
+** Primitive procedures are now VM trampoline procedures
+
+It used to be that there were something like 12 different typecodes
+allocated to primitive procedures, each with its own calling convention.
+Now there is only one, the gsubr. This may affect user code if you were
+defining a procedure using scm_c_make_subr rather scm_c_make_gsubr. The
+solution is to switch to use scm_c_make_gsubr. This solution works well
+both with the old 1.8 and and with the current 1.9 branch.
+
+Guile's old evaluator used to have special cases for applying "gsubrs",
+primitive procedures with specified numbers of required, optional, and
+rest arguments. Now, however, Guile represents gsubrs as normal VM
+procedures, with appropriate bytecode to parse out the correct number of
+arguments, including optional and rest arguments, and then with a
+special bytecode to apply the gsubr.
+
+This allows primitive procedures to appear on the VM stack, allowing
+them to be accurately counted in profiles. Also they now have more
+debugging information attached to them -- their number of arguments, for
+example. In addition, the VM can completely inline the application
+mechanics, allowing for faster primitive calls.
+
+However there are some changes on the C level. There is no more
+`scm_tc7_gsubr' or `scm_tcs_subrs' typecode for primitive procedures, as
+they are just VM procedures. Likewise the macros `SCM_GSUBR_TYPE',
+`SCM_GSUBR_MAKTYPE', `SCM_GSUBR_REQ', `SCM_GSUBR_OPT', and
+`SCM_GSUBR_REST' are gone, as are `SCM_SUBR_META_INFO', `SCM_SUBR_PROPS'
+`SCM_SET_SUBR_GENERIC_LOC', and `SCM_SUBR_ARITY_TO_TYPE'.
+
+Perhaps more significantly, `scm_c_make_subr',
+`scm_c_make_subr_with_generic', `scm_c_define_subr', and
+`scm_c_define_subr_with_generic'. They all operated on subr typecodes,
+and there are no more subr typecodes. Use the scm_c_make_gsubr family
+instead.
+
+Normal users of gsubrs should not be affected, though, as the
+scm_c_make_gsubr family still is the correct way to create primitive
+procedures.
+
+** Remove deprecated array C interfaces
+
+Removed the deprecated array functions `scm_i_arrayp',
+`scm_i_array_ndim', `scm_i_array_mem', `scm_i_array_v',
+`scm_i_array_base', `scm_i_array_dims', and the deprecated macros
+`SCM_ARRAYP', `SCM_ARRAY_NDIM', `SCM_ARRAY_CONTP', `SCM_ARRAY_MEM',
+`SCM_ARRAY_V', `SCM_ARRAY_BASE', and `SCM_ARRAY_DIMS'.
+
+** Remove unused snarf macros
+
+`SCM_DEFINE1', `SCM_PRIMITIVE_GENERIC_1', `SCM_PROC1, and `SCM_GPROC1'
+are no more. Use SCM_DEFINE or SCM_PRIMITIVE_GENERIC instead.
+
+** New functions: `scm_call_n', `scm_c_run_hookn'
+
+`scm_call_n' applies to apply a function to an array of arguments.
+`scm_c_run_hookn' runs a hook with an array of arguments.
+
+** Some SMOB types changed to have static typecodes
+
+Fluids, dynamic states, and hash tables used to be SMOB objects, but now
+they have statically allocated tc7 typecodes.
+
+** Preparations for changing SMOB representation
+
+If things go right, we'll be changing the SMOB representation soon. To
+that end, we did a lot of cleanups to calls to e.g. SCM_CELL_WORD_2(x) when
+the code meant SCM_SMOB_DATA_2(x); user code will need similar changes
+in the future. Code accessing SMOBs using SCM_CELL macros was never
+correct, but until now things still worked. Users should be aware of
+such changes.
+
+** Changed invocation mechanics of applicable SMOBs
+
+Guile's old evaluator used to have special cases for applying SMOB
+objects. Now, with the VM, when Guile sees a SMOB, it looks up a VM
+trampoline procedure for it, and use the normal mechanics to apply the
+trampoline. This simplifies procedure application in the normal,
+non-SMOB case.
+
+The upshot is that the mechanics used to apply a SMOB are different from
+1.8. Descriptors no longer have `apply_0', `apply_1', `apply_2', and
+`apply_3' functions, and the macros SCM_SMOB_APPLY_0 and friends are now
+deprecated. Just use the scm_call_0 family of procedures.
+
+** Removed support shlibs for SRFIs 1, 4, 13, 14, and 60
+
+Though these SRFI support libraries did expose API, they encoded a
+strange version string into their library names. That version was never
+programmatically exported, so there was no way people could use the
+libs.
+
+This was a fortunate oversight, as it allows us to remove the need for
+extra, needless shared libraries --- the C support code for SRFIs 4, 13,
+and 14 was already in core --- and allow us to incrementally return the
+SRFI implementation to Scheme.
+
+** New C function: scm_module_public_interface
+
+This procedure corresponds to Scheme's `module-public-interface'.
+
+** Undeprecate `scm_the_root_module ()'
+
+It's useful to be able to get the root module from C without doing a
+full module lookup.
+
+** Inline vector allocation
+
+Instead of having vectors point out into the heap for their data, their
+data is now allocated inline to the vector object itself. The same is
+true for bytevectors, by default, though there is an indirection
+available which should allow for making a bytevector from an existing
+memory region.
+
+** New struct constructors that don't involve making lists
+
+`scm_c_make_struct' and `scm_c_make_structv' are new varargs and array
+constructors, respectively, for structs. You might find them useful.
+
+** Stack refactor
+
+In Guile 1.8, there were debugging frames on the C stack. Now there is
+no more need to explicitly mark the stack in this way, because Guile has
+a VM stack that it knows how to walk, which simplifies the C API
+considerably. See the ChangeLog for details; the relevant interface is
+in libguile/stacks.h. The Scheme API has not been changed significantly.
+
+** Removal of Guile's primitive object system.
+
+There were a number of pieces in `objects.[ch]' that tried to be a
+minimal object system, but were never documented, and were quickly
+obseleted by GOOPS' merge into Guile proper. So `scm_make_class_object',
+`scm_make_subclass_object', `scm_metaclass_standard', and like symbols
+from objects.h are no more. In the very unlikely case in which these
+were useful to you, we urge you to contact guile-devel.
+
+** No future.
+
+Actually the future is still in the state that it was, is, and ever
+shall be, Amen, except that `futures.c' and `futures.h' are no longer a
+part of it. These files were experimental, never compiled, and would be
+better implemented in Scheme anyway. In the future, that is.
+
+** Deprecate trampolines
+
+There used to be C functions `scm_trampoline_0', `scm_trampoline_1', and
+so on. The point was to do some precomputation on the type of the
+procedure, then return a specialized "call" procedure. However this
+optimization wasn't actually an optimization, so it is now deprecated.
+Just use `scm_call_0', etc instead.
+
+** Deprecated `scm_badargsp'
+
+This function is unused in Guile, but was part of its API.
+
+** Better support for Lisp `nil'.
+
+The bit representation of `nil' has been tweaked so that it is now very
+efficient to check e.g. if a value is equal to Scheme's end-of-list or
+Lisp's nil. Additionally there are a heap of new, specific predicates
+like scm_is_null_or_nil.
+
+** Better integration of Lisp `nil'.
+
+`scm_is_boolean', `scm_is_false', and `scm_is_null' all return true now
+for Lisp's `nil'. This shouldn't affect any Scheme code at this point,
+but when we start to integrate more with Emacs, it is possible that we
+break code that assumes that, for example, `(not x)' implies that `x' is
+`eq?' to `#f'. This is not a common assumption. Refactoring affected
+code to rely on properties instead of identities will improve code
+correctness. See "Nil" in the manual, for more details.
+
+** Support for static allocation of strings, symbols, and subrs.
+
+Calls to snarfing CPP macros like SCM_DEFINE macro will now allocate
+much of their associated data as static variables, reducing Guile's
+memory footprint.
+
+** `scm_stat' has an additional argument, `exception_on_error'
+** `scm_primitive_load_path' has an additional argument `exception_on_not_found'
+
+** `scm_set_port_seek' and `scm_set_port_truncate' use the `scm_t_off' type
+
+Previously they would use the `off_t' type, which is fragile since its
+definition depends on the application's value for `_FILE_OFFSET_BITS'.
+
+** The `long_long' C type, deprecated in 1.8, has been removed
+
+** Removed deprecated uniform array procedures: scm_make_uve,
+ scm_array_prototype, scm_list_to_uniform_array,
+ scm_dimensions_to_uniform_array, scm_make_ra, scm_shap2ra, scm_cvref,
+ scm_ra_set_contp, scm_aind, scm_raprin1
+
+These functions have been deprecated since early 2005.
+
+* Changes to the distribution
+
+** Guile's license is now LGPLv3+
+
+In other words the GNU Lesser General Public License, version 3 or
+later (at the discretion of each person that chooses to redistribute
+part of Guile).
+
+** AM_SILENT_RULES
+
+Guile's build is visually quieter, due to the use of Automake 1.11's
+AM_SILENT_RULES. Build as `make V=1' to see all of the output.
+
+** GOOPS documentation folded into Guile reference manual
+
+GOOPS, Guile's object system, used to be documented in separate manuals.
+This content is now included in Guile's manual directly.
+
+** `guile-config' will be deprecated in favor of `pkg-config'
+
+`guile-config' has been rewritten to get its information from
+`pkg-config', so this should be a transparent change. Note however that
+guile.m4 has yet to be modified to call pkg-config instead of
+guile-config.
+
+** Guile now provides `guile-2.0.pc' instead of `guile-1.8.pc'
+
+Programs that use `pkg-config' to find Guile or one of its Autoconf
+macros should now require `guile-2.0' instead of `guile-1.8'.
+
+** New installation directory: $(pkglibdir)/1.9/ccache
+
+If $(libdir) is /usr/lib, for example, Guile will install its .go files
+to /usr/lib/guile/1.9/ccache. These files are architecture-specific.
+
+** Parallel installability fixes
+
+Guile now installs its header files to a effective-version-specific
+directory, and includes the effective version (e.g. 2.0) in the library
+name (e.g. libguile-2.0.so).
+
+This change should be transparent to users, who should detect Guile via
+the guile.m4 macro, or the guile-2.0.pc pkg-config file. It will allow
+parallel installs for multiple versions of Guile development
+environments.
+
+** Dynamically loadable extensions may be placed in a Guile-specific path
+
+Before, Guile only searched the system library paths for extensions
+(e.g. /usr/lib), which meant that the names of Guile extensions had to
+be globally unique. Installing them to a Guile-specific extensions
+directory is cleaner. Use `pkg-config --variable=extensiondir
+guile-2.0' to get the location of the extensions directory.
+
+** User Scheme code may be placed in a version-specific path
+
+Before, there was only one way to install user Scheme code to a
+version-specific Guile directory: install to Guile's own path,
+e.g. /usr/share/guile/2.0. The site directory,
+e.g. /usr/share/guile/site, was unversioned. This has been changed to
+add a version-specific site directory, e.g. /usr/share/guile/site/2.0,
+searched before the global site directory.
+
+** New dependency: libgc
+
+See http://www.hpl.hp.com/personal/Hans_Boehm/gc/, for more information.
+
+** New dependency: GNU libunistring
+
+See http://www.gnu.org/software/libunistring/, for more information. Our
+Unicode support uses routines from libunistring.
+
+** New dependency: libffi
+
+See http://sourceware.org/libffi/, for more information.
+
\f
-Changes in 1.8.6 (since 1.8.5)
+Changes in 1.8.8 (since 1.8.7)
* Bugs fixed
-** Internal `scm_i_' functions now have "hidden" linkage with GCC/ELF
+** Fix possible buffer overruns when parsing numbers
+** Avoid clash with system setjmp/longjmp on IA64
+** Fix `wrong type arg' exceptions with IPv6 addresses
-This makes these internal functions technically not callable from
-application code.
+\f
+Changes in 1.8.7 (since 1.8.6)
+
+* New modules (see the manual for details)
+
+** `(srfi srfi-98)', an interface to access environment variables
+
+* Bugs fixed
+
+** Fix compilation with `--disable-deprecated'
+** Fix %fast-slot-ref/set!, to avoid possible segmentation fault
+** Fix MinGW build problem caused by HAVE_STRUCT_TIMESPEC confusion
+** Fix build problem when scm_t_timespec is different from struct timespec
+** Fix build when compiled with -Wundef -Werror
+** More build fixes for `alphaev56-dec-osf5.1b' (Tru64)
+** Build fixes for `powerpc-ibm-aix5.3.0.0' (AIX 5.3)
+** With GCC, always compile with `-mieee' on `alpha*' and `sh*'
+** Better diagnose broken `(strftime "%z" ...)' in `time.test' (bug #24130)
+** Fix parsing of SRFI-88/postfix keywords longer than 128 characters
+** Fix reading of complex numbers where both parts are inexact decimals
+
+** Allow @ macro to work with (ice-9 syncase)
+
+Previously, use of the @ macro in a module whose code is being
+transformed by (ice-9 syncase) would cause an "Invalid syntax" error.
+Now it works as you would expect (giving the value of the specified
+module binding).
+
+** Have `scm_take_locale_symbol ()' return an interned symbol (bug #25865)
+
+\f
+Changes in 1.8.6 (since 1.8.5)
+
+* New features (see the manual for details)
+
+** New convenience function `scm_c_symbol_length ()'
+
+** Single stepping through code from Emacs
+
+When you use GDS to evaluate Scheme code from Emacs, you can now use
+`C-u' to indicate that you want to single step through that code. See
+`Evaluating Scheme Code' in the manual for more details.
+
+** New "guile(1)" man page!
+
+* Changes to the distribution
-** Fix build issue on Tru64
+** Automake's `AM_MAINTAINER_MODE' is no longer used
+
+Thus, the `--enable-maintainer-mode' configure option is no longer
+available: Guile is now always configured in "maintainer mode".
+
+** `ChangeLog' files are no longer updated
+
+Instead, changes are detailed in the version control system's logs. See
+the top-level `ChangeLog' files for details.
+
+
+* Bugs fixed
+
+** `symbol->string' now returns a read-only string, as per R5RS
+** Fix incorrect handling of the FLAGS argument of `fold-matches'
+** `guile-config link' now prints `-L$libdir' before `-lguile'
+** Fix memory corruption involving GOOPS' `class-redefinition'
+** Fix possible deadlock in `mutex-lock'
+** Fix build issue on Tru64 and ia64-hp-hpux11.23 (`SCM_UNPACK' macro)
+** Fix build issue on mips, mipsel, powerpc and ia64 (stack direction)
+** Fix build issue on hppa2.0w-hp-hpux11.11 (`dirent64' and `readdir64_r')
+** Fix build issue on i386-unknown-freebsd7.0 ("break strict-aliasing rules")
+** Fix misleading output from `(help rationalize)'
+** Fix build failure on Debian hppa architecture (bad stack growth detection)
+** Fix `gcd' when called with a single, negative argument.
+** Fix `Stack overflow' errors seen when building on some platforms
+** Fix bug when `scm_with_guile ()' was called several times from the
+ same thread
+** The handler of SRFI-34 `with-exception-handler' is now invoked in the
+ dynamic environment of the call to `raise'
+** Fix potential deadlock in `make-struct'
+** Fix compilation problem with libltdl from Libtool 2.2.x
+** Fix sloppy bound checking in `string-{ref,set!}' with the empty string
\f
Changes in 1.8.5 (since 1.8.4)
** Fixed shadowing of libc's <random.h> on Tru64, which broke compilation
** Make sure all tests honor `$TMPDIR'
-* Changes to the distribution
-
-** New FAQ
-
-We've started collecting Frequently Asked Questions (FAQ), and will
-distribute these (with answers!) in future Guile releases.
-
\f
Changes in 1.8.4 (since 1.8.3)
** The reader is now faster, which reduces startup time
** Procedures returned by `record-accessor' and `record-modifier' are faster
-
\f
Changes in 1.8.2 (since 1.8.1):
** set-program-arguments
** make-vtable
+* Incompatible changes
+
+** The body of a top-level `define' no longer sees the binding being created
+
+In a top-level `define', the binding being created is no longer visible
+from the `define' body. This breaks code like
+"(define foo (begin (set! foo 1) (+ foo 1)))", where `foo' is now
+unbound in the body. However, such code was not R5RS-compliant anyway,
+per Section 5.2.1.
+
* Bugs fixed
** Fractions were not `equal?' if stored in unreduced form.
** scm_exp - [C]
** scm_sqrt - [C]
-* New `(ice-9 i18n)' module (see the manual for details)
-
* Bugs fixed
** Build problems have been fixed on MacOS, SunOS, and QNX.
HCoop / bpt / guile.git / blobdiff