1 /* Copyright (C) 1996,1997,1998,1999,2000,2001 Free Software Foundation, Inc.
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2, or (at your option)
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this software; see the file COPYING. If not, write to
15 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
16 * Boston, MA 02111-1307 USA
18 * As a special exception, the Free Software Foundation gives permission
19 * for additional uses of the text contained in its release of GUILE.
21 * The exception is that, if you link the GUILE library with other files
22 * to produce an executable, this does not by itself cause the
23 * resulting executable to be covered by the GNU General Public License.
24 * Your use of that executable is in no way restricted on account of
25 * linking the GUILE library code into it.
27 * This exception does not however invalidate any other reasons why
28 * the executable file might be covered by the GNU General Public License.
30 * This exception applies only to the code released by the
31 * Free Software Foundation under the name GUILE. If you copy
32 * code from other Free Software Foundation releases into a copy of
33 * GUILE, as the General Public License permits, the exception does
34 * not apply to the code that you add in this way. To avoid misleading
35 * anyone as to the status of such modified files, you must delete
36 * this exception notice from them.
38 * If you write modifications of your own for GUILE, it is your choice
39 * whether to permit this exception to apply to your modifications.
40 * If you do not wish that, delete this exception notice. */
42 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
43 gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
47 #include "libguile/_scm.h"
48 #include "libguile/chars.h"
49 #include "libguile/eval.h"
50 #include "libguile/alist.h"
51 #include "libguile/weaks.h"
52 #include "libguile/hashtab.h"
53 #include "libguile/ports.h"
54 #include "libguile/strings.h"
56 #include "libguile/validate.h"
57 #include "libguile/struct.h"
65 static SCM required_vtable_fields
= SCM_BOOL_F
;
69 SCM_DEFINE (scm_make_struct_layout
, "make-struct-layout", 1, 0, 0,
71 "Return a new structure layout object.\n\n"
72 "@var{fields} must be a string made up of pairs of characters\n"
73 "strung together. The first character of each pair describes a field\n"
74 "type, the second a field protection. Allowed types are 'p' for\n"
75 "GC-protected Scheme data, 'u' for unprotected binary data, and 's' for\n"
76 "a field that points to the structure itself. Allowed protections\n"
77 "are 'w' for mutable fields, 'r' for read-only fields, and 'o' for opaque \n"
78 "fields. The last field protection specification may be capitalized to\n"
79 "indicate that the field is a tail-array.")
80 #define FUNC_NAME s_scm_make_struct_layout
83 SCM_VALIDATE_STRING (1, fields
);
90 len
= SCM_STRING_LENGTH (fields
);
92 SCM_MISC_ERROR ("odd length field specification: ~S",
95 field_desc
= SCM_STRING_CHARS (fields
);
97 for (x
= 0; x
< len
; x
+= 2)
99 switch (field_desc
[x
])
110 SCM_MISC_ERROR ("unrecognized field type: ~S",
111 SCM_LIST1 (SCM_MAKE_CHAR (field_desc
[x
])));
114 switch (field_desc
[x
+ 1])
117 if (field_desc
[x
] == 's')
118 SCM_MISC_ERROR ("self fields not writable", SCM_EOL
);
125 if (field_desc
[x
] == 's')
126 SCM_MISC_ERROR ("self fields not allowed in tail array",
129 SCM_MISC_ERROR ("tail array field must be last field in layout",
133 SCM_MISC_ERROR ("unrecognized ref specification: ~S",
134 SCM_LIST1 (SCM_MAKE_CHAR (field_desc
[x
+ 1])));
137 if (field_desc
[x
] == 'd')
139 if (field_desc
[x
+ 2] != '-')
140 SCM_MISC_ERROR ("missing dash field at position ~A",
141 SCM_LIST1 (SCM_MAKINUM (x
/ 2)));
147 new_sym
= scm_mem2symbol (field_desc
, len
);
149 return scm_return_first (new_sym
, fields
);
158 scm_struct_init (SCM handle
, SCM layout
, scm_bits_t
* mem
, int tail_elts
, SCM inits
)
160 unsigned char * fields_desc
= (unsigned char *) SCM_SYMBOL_CHARS (layout
) - 2;
161 unsigned char prot
= 0;
162 int n_fields
= SCM_SYMBOL_LENGTH (layout
) / 2;
170 prot
= fields_desc
[1];
171 if (SCM_LAYOUT_TAILP (prot
))
174 prot
= prot
== 'R' ? 'r' : prot
== 'W' ? 'w' : 'o';
176 n_fields
+= tail_elts
- 1;
182 switch (*fields_desc
)
186 if ((prot
!= 'r' && prot
!= 'w') || inits
== SCM_EOL
)
190 *mem
= scm_num2long (SCM_CAR (inits
), SCM_ARGn
, "scm_struct_init");
191 inits
= SCM_CDR (inits
);
197 if ((prot
!= 'r' && prot
!= 'w') || SCM_NULLP (inits
))
201 *mem
= scm_num2ulong (SCM_CAR (inits
),
204 inits
= SCM_CDR (inits
);
209 if ((prot
!= 'r' && prot
!= 'w') || SCM_NULLP (inits
))
210 *mem
= SCM_UNPACK (SCM_BOOL_F
);
213 *mem
= SCM_UNPACK (SCM_CAR (inits
));
214 inits
= SCM_CDR (inits
);
221 if ((prot
!= 'r' && prot
!= 'w') || inits
== SCM_EOL
)
222 *((double *)mem
) = 0.0;
225 *mem
= scm_num2dbl (SCM_CAR (inits
), "scm_struct_init");
226 inits
= SCM_CDR (inits
);
233 *mem
= SCM_UNPACK (handle
);
243 SCM_DEFINE (scm_struct_p
, "struct?", 1, 0, 0,
245 "Return @code{#t} iff @var{obj} is a structure object, else\n"
247 #define FUNC_NAME s_scm_struct_p
249 return SCM_BOOL(SCM_STRUCTP (x
));
253 SCM_DEFINE (scm_struct_vtable_p
, "struct-vtable?", 1, 0, 0,
255 "Return @code{#t} iff obj is a vtable structure.")
256 #define FUNC_NAME s_scm_struct_vtable_p
261 if (!SCM_STRUCTP (x
))
264 layout
= SCM_STRUCT_LAYOUT (x
);
266 if (SCM_SYMBOL_LENGTH (layout
) < SCM_STRING_LENGTH (required_vtable_fields
))
269 if (strncmp (SCM_SYMBOL_CHARS (layout
), SCM_STRING_CHARS (required_vtable_fields
),
270 SCM_STRING_LENGTH (required_vtable_fields
)))
273 mem
= SCM_STRUCT_DATA (x
);
278 return SCM_BOOL (SCM_SYMBOLP (SCM_PACK (mem
[0])));
283 /* All struct data must be allocated at an address whose bottom three
284 bits are zero. This is because the tag for a struct lives in the
285 bottom three bits of the struct's car, and the upper bits point to
286 the data of its vtable, which is a struct itself. Thus, if the
287 address of that data doesn't end in three zeros, tagging it will
290 This function allocates a block of memory, and returns a pointer at
291 least scm_struct_n_extra_words words into the block. Furthermore,
292 it guarantees that that pointer's least three significant bits are
295 The argument n_words should be the number of words that should
296 appear after the returned address. (That is, it shouldn't include
297 scm_struct_n_extra_words.)
299 This function initializes the following fields of the struct:
301 scm_struct_i_ptr --- the actual start of the block of memory; the
302 address you should pass to 'free' to dispose of the block.
303 This field allows us to both guarantee that the returned
304 address is divisible by eight, and allow the GC to free the
307 scm_struct_i_n_words --- the number of words allocated to the
308 block, including the extra fields. This is used by the GC.
314 scm_alloc_struct (int n_words
, int n_extra
, char *who
)
316 int size
= sizeof (scm_bits_t
) * (n_words
+ n_extra
) + 7;
317 void * block
= scm_must_malloc (size
, who
);
319 /* Adjust the pointer to hide the extra words. */
320 scm_bits_t
* p
= (scm_bits_t
*) block
+ n_extra
;
322 /* Adjust it even further so it's aligned on an eight-byte boundary. */
323 p
= (scm_bits_t
*) (((scm_bits_t
) p
+ 7) & ~7);
325 /* Initialize a few fields as described above. */
326 p
[scm_struct_i_free
] = (scm_bits_t
) scm_struct_free_standard
;
327 p
[scm_struct_i_ptr
] = (scm_bits_t
) block
;
328 p
[scm_struct_i_n_words
] = n_words
;
329 p
[scm_struct_i_flags
] = 0;
335 scm_struct_free_0 (scm_bits_t
* vtable
, scm_bits_t
* data
)
341 scm_struct_free_light (scm_bits_t
* vtable
, scm_bits_t
* data
)
343 scm_must_free (data
);
344 return vtable
[scm_struct_i_size
] & ~SCM_STRUCTF_MASK
;
348 scm_struct_free_standard (scm_bits_t
* vtable
, scm_bits_t
* data
)
350 size_t n
= (data
[scm_struct_i_n_words
] + scm_struct_n_extra_words
)
351 * sizeof (scm_bits_t
) + 7;
352 scm_must_free ((void *) data
[scm_struct_i_ptr
]);
357 scm_struct_free_entity (scm_bits_t
* vtable
, scm_bits_t
* data
)
359 size_t n
= (data
[scm_struct_i_n_words
] + scm_struct_entity_n_extra_words
)
360 * sizeof (scm_bits_t
) + 7;
361 scm_must_free ((void *) data
[scm_struct_i_ptr
]);
366 scm_struct_gc_init (void *dummy1
, void *dummy2
, void *dummy3
)
368 scm_structs_to_free
= SCM_EOL
;
373 scm_free_structs (void *dummy1
, void *dummy2
, void *dummy3
)
375 SCM newchain
= scm_structs_to_free
;
378 /* Mark vtables in GC chain. GC mark set means delay freeing. */
379 SCM chain
= newchain
;
380 while (SCM_NNULLP (chain
))
382 SCM vtable
= SCM_STRUCT_VTABLE (chain
);
383 if (SCM_STRUCT_GC_CHAIN (vtable
) != 0 && vtable
!= chain
)
384 SCM_SETGCMARK (vtable
);
385 chain
= SCM_STRUCT_GC_CHAIN (chain
);
387 /* Free unmarked structs. */
390 while (SCM_NNULLP (chain
))
393 chain
= SCM_STRUCT_GC_CHAIN (chain
);
394 if (SCM_GCMARKP (obj
))
397 SCM_SET_STRUCT_GC_CHAIN (obj
, newchain
);
402 scm_bits_t word0
= SCM_CELL_WORD_0 (obj
) - scm_tc3_cons_gloc
;
403 /* access as struct */
404 scm_bits_t
* vtable_data
= (scm_bits_t
*) word0
;
405 scm_bits_t
* data
= (scm_bits_t
*) SCM_UNPACK (SCM_CDR (obj
));
406 scm_struct_free_t free_struct_data
407 = ((scm_struct_free_t
) vtable_data
[scm_struct_i_free
]);
408 SCM_SET_CELL_TYPE (obj
, scm_tc_free_cell
);
409 free_struct_data (vtable_data
, data
);
413 while (SCM_NNULLP (newchain
));
417 SCM_DEFINE (scm_make_struct
, "make-struct", 2, 0, 1,
418 (SCM vtable
, SCM tail_array_size
, SCM init
),
419 "Create a new structure.\n\n"
420 "@var{type} must be a vtable structure (@pxref{Vtables}).\n\n"
421 "@var{tail-elts} must be a non-negative integer. If the layout\n"
422 "specification indicated by @var{type} includes a tail-array,\n"
423 "this is the number of elements allocated to that array.\n\n"
424 "The @var{init1}, @dots{} are optional arguments describing how\n"
425 "successive fields of the structure should be initialized. Only fields\n"
426 "with protection 'r' or 'w' can be initialized, except for fields of\n"
427 "type 's', which are automatically initialized to point to the new\n"
428 "structure itself; fields with protection 'o' can not be initialized by\n"
429 "Scheme programs.\n\n"
430 "If fewer optional arguments than initializable fields are supplied,\n"
431 "fields of type 'p' get default value #f while fields of type 'u' are\n"
432 "initialized to 0.\n\n"
433 "Structs are currently the basic representation for record-like data\n"
434 "structures in Guile. The plan is to eventually replace them with a\n"
435 "new representation which will at the same time be easier to use and\n"
437 "For more information, see the documentation for @code{make-vtable-vtable}.")
438 #define FUNC_NAME s_scm_make_struct
446 SCM_VALIDATE_VTABLE (1,vtable
);
447 SCM_VALIDATE_INUM (2,tail_array_size
);
448 SCM_VALIDATE_REST_ARGUMENT (init
);
450 layout
= SCM_PACK (SCM_STRUCT_DATA (vtable
) [scm_vtable_index_layout
]);
451 basic_size
= SCM_SYMBOL_LENGTH (layout
) / 2;
452 tail_elts
= SCM_INUM (tail_array_size
);
453 SCM_NEWCELL2 (handle
);
455 if (SCM_STRUCT_DATA (vtable
)[scm_struct_i_flags
] & SCM_STRUCTF_ENTITY
)
457 data
= scm_alloc_struct (basic_size
+ tail_elts
,
458 scm_struct_entity_n_extra_words
,
460 data
[scm_struct_i_procedure
] = SCM_UNPACK (SCM_BOOL_F
);
461 data
[scm_struct_i_setter
] = SCM_UNPACK (SCM_BOOL_F
);
464 data
= scm_alloc_struct (basic_size
+ tail_elts
,
465 scm_struct_n_extra_words
,
467 SCM_SET_CELL_WORD_1 (handle
, data
);
468 SCM_SET_STRUCT_GC_CHAIN (handle
, 0);
469 scm_struct_init (handle
, layout
, data
, tail_elts
, init
);
470 SCM_SET_CELL_WORD_0 (handle
, (scm_bits_t
) SCM_STRUCT_DATA (vtable
) + scm_tc3_cons_gloc
);
478 SCM_DEFINE (scm_make_vtable_vtable
, "make-vtable-vtable", 2, 0, 1,
479 (SCM user_fields
, SCM tail_array_size
, SCM init
),
480 "Return a new, self-describing vtable structure.\n\n"
481 "@var{user-fields} is a string describing user defined fields of the\n"
482 "vtable beginning at index @code{vtable-offset-user}\n"
483 "(see @code{make-struct-layout}).\n\n"
484 "@var{tail-size} specifies the size of the tail-array (if any) of\n"
486 "@var{init1}, @dots{} are the optional initializers for the fields of\n"
488 "Vtables have one initializable system field---the struct printer.\n"
489 "This field comes before the user fields in the initializers passed\n"
490 "to @code{make-vtable-vtable} and @code{make-struct}, and thus works as\n"
491 "a third optional argument to @code{make-vtable-vtable} and a fourth to\n"
492 "@code{make-struct} when creating vtables:\n\n"
493 "If the value is a procedure, it will be called instead of the standard\n"
494 "printer whenever a struct described by this vtable is printed.\n"
495 "The procedure will be called with arguments STRUCT and PORT.\n\n"
496 "The structure of a struct is described by a vtable, so the vtable is\n"
497 "in essence the type of the struct. The vtable is itself a struct with\n"
498 "a vtable. This could go on forever if it weren't for the\n"
499 "vtable-vtables which are self-describing vtables, and thus terminate\n"
501 "There are several potential ways of using structs, but the standard\n"
502 "one is to use three kinds of structs, together building up a type\n"
503 "sub-system: one vtable-vtable working as the root and one or several\n"
504 "\"types\", each with a set of \"instances\". (The vtable-vtable should be\n"
505 "compared to the class <class> which is the class of itself.)\n\n"
507 "(define ball-root (make-vtable-vtable \"pr\" 0))\n\n"
508 "(define (make-ball-type ball-color)\n"
509 " (make-struct ball-root 0\n"
510 " (make-struct-layout \"pw\")\n"
511 " (lambda (ball port)\n"
512 " (format port \"#<a ~A ball owned by ~A>\"\n"
516 "(define (color ball) (struct-ref (struct-vtable ball) vtable-offset-user))\n"
517 "(define (owner ball) (struct-ref ball 0))\n\n"
518 "(define red (make-ball-type 'red))\n"
519 "(define green (make-ball-type 'green))\n\n"
520 "(define (make-ball type owner) (make-struct type 0 owner))\n\n"
521 "(define ball (make-ball green 'Nisse))\n"
522 "ball @result{} #<a green ball owned by Nisse>\n"
524 #define FUNC_NAME s_scm_make_vtable_vtable
533 SCM_VALIDATE_STRING (1, user_fields
);
534 SCM_VALIDATE_INUM (2, tail_array_size
);
535 SCM_VALIDATE_REST_ARGUMENT (init
);
537 fields
= scm_string_append (SCM_LIST2 (required_vtable_fields
, user_fields
));
538 layout
= scm_make_struct_layout (fields
);
539 basic_size
= SCM_SYMBOL_LENGTH (layout
) / 2;
540 tail_elts
= SCM_INUM (tail_array_size
);
541 SCM_NEWCELL2 (handle
);
543 data
= scm_alloc_struct (basic_size
+ tail_elts
,
544 scm_struct_n_extra_words
,
545 "make-vtable-vtable");
546 SCM_SET_CELL_WORD_1 (handle
, data
);
547 SCM_SET_STRUCT_GC_CHAIN (handle
, 0);
548 data
[scm_vtable_index_layout
] = SCM_UNPACK (layout
);
549 scm_struct_init (handle
, layout
, data
, tail_elts
, scm_cons (layout
, init
));
550 SCM_SET_CELL_WORD_0 (handle
, (scm_bits_t
) data
+ scm_tc3_cons_gloc
);
559 SCM_DEFINE (scm_struct_ref
, "struct-ref", 2, 0, 0,
560 (SCM handle
, SCM pos
),
561 "@deffnx primitive struct-set! struct n value\n"
562 "Access (or modify) the @var{n}th field of @var{struct}.\n\n"
563 "If the field is of type 'p', then it can be set to an arbitrary value.\n\n"
564 "If the field is of type 'u', then it can only be set to a non-negative\n"
565 "integer value small enough to fit in one machine word.")
566 #define FUNC_NAME s_scm_struct_ref
568 SCM answer
= SCM_UNDEFINED
;
577 SCM_VALIDATE_STRUCT (1,handle
);
578 SCM_VALIDATE_INUM (2,pos
);
580 layout
= SCM_STRUCT_LAYOUT (handle
);
581 data
= SCM_STRUCT_DATA (handle
);
584 fields_desc
= SCM_SYMBOL_CHARS (layout
);
585 n_fields
= data
[scm_struct_i_n_words
];
587 SCM_ASSERT_RANGE(1,pos
, p
< n_fields
);
589 if (p
* 2 < SCM_SYMBOL_LENGTH (layout
))
592 field_type
= fields_desc
[p
* 2];
593 ref
= fields_desc
[p
* 2 + 1];
594 if ((ref
!= 'r') && (ref
!= 'w'))
596 if ((ref
== 'R') || (ref
== 'W'))
599 SCM_MISC_ERROR ("ref denied for field ~A", SCM_LIST1 (pos
));
602 else if (fields_desc
[SCM_SYMBOL_LENGTH (layout
) - 1] != 'O')
603 field_type
= fields_desc
[SCM_SYMBOL_LENGTH (layout
) - 2];
605 SCM_MISC_ERROR ("ref denied for field ~A", SCM_LIST1 (pos
));
610 answer
= scm_ulong2num (data
[p
]);
615 answer
= scm_long2num (data
[p
]);
619 answer
= scm_make_real (*((double *)&(data
[p
])));
625 answer
= SCM_PACK (data
[p
]);
630 SCM_MISC_ERROR ("unrecognized field type: ~S",
631 SCM_LIST1 (SCM_MAKE_CHAR (field_type
)));
639 SCM_DEFINE (scm_struct_set_x
, "struct-set!", 3, 0, 0,
640 (SCM handle
, SCM pos
, SCM val
),
641 "Set the slot of the structure @var{handle} with index @var{pos}\n"
642 "to @var{val}. Signal an error if the slot can not be written\n"
644 #define FUNC_NAME s_scm_struct_set_x
653 SCM_VALIDATE_STRUCT (1,handle
);
654 SCM_VALIDATE_INUM (2,pos
);
656 layout
= SCM_STRUCT_LAYOUT (handle
);
657 data
= SCM_STRUCT_DATA (handle
);
660 fields_desc
= SCM_SYMBOL_CHARS (layout
);
661 n_fields
= data
[scm_struct_i_n_words
];
663 SCM_ASSERT_RANGE (1,pos
, p
< n_fields
);
665 if (p
* 2 < SCM_SYMBOL_LENGTH (layout
))
668 field_type
= fields_desc
[p
* 2];
669 set_x
= fields_desc
[p
* 2 + 1];
671 SCM_MISC_ERROR ("set! denied for field ~A", SCM_LIST1 (pos
));
673 else if (fields_desc
[SCM_SYMBOL_LENGTH (layout
) - 1] == 'W')
674 field_type
= fields_desc
[SCM_SYMBOL_LENGTH (layout
) - 2];
676 SCM_MISC_ERROR ("set! denied for field ~A", SCM_LIST1 (pos
));
681 data
[p
] = SCM_NUM2ULONG (3, val
);
686 data
[p
] = SCM_NUM2LONG (3,val
);
690 *((double *)&(data
[p
])) = scm_num2dbl (val
, (char *)SCM_ARG3
);
695 data
[p
] = SCM_UNPACK (val
);
699 SCM_MISC_ERROR ("self fields immutable", SCM_EOL
);
702 SCM_MISC_ERROR ("unrecognized field type: ~S",
703 SCM_LIST1 (SCM_MAKE_CHAR (field_type
)));
711 SCM_DEFINE (scm_struct_vtable
, "struct-vtable", 1, 0, 0,
713 "Return the vtable structure that describes the type of @var{struct}.")
714 #define FUNC_NAME s_scm_struct_vtable
716 SCM_VALIDATE_STRUCT (1,handle
);
717 return SCM_STRUCT_VTABLE (handle
);
722 SCM_DEFINE (scm_struct_vtable_tag
, "struct-vtable-tag", 1, 0, 0,
724 "Return the vtable tag of the structure @var{handle}.")
725 #define FUNC_NAME s_scm_struct_vtable_tag
727 SCM_VALIDATE_VTABLE (1,handle
);
728 return scm_long2num ((long) SCM_STRUCT_DATA (handle
) >> 3);
732 /* {Associating names and classes with vtables}
734 * The name of a vtable should probably be stored as a slot. This is
735 * a backward compatible solution until agreement has been achieved on
736 * how to associate names with vtables.
740 scm_struct_ihashq (SCM obj
, unsigned int n
)
742 /* The length of the hash table should be a relative prime it's not
743 necessary to shift down the address. */
744 return SCM_UNPACK (obj
) % n
;
748 scm_struct_create_handle (SCM obj
)
750 SCM handle
= scm_hash_fn_create_handle_x (scm_struct_table
,
756 if (SCM_FALSEP (SCM_CDR (handle
)))
757 SCM_SETCDR (handle
, scm_cons (SCM_BOOL_F
, SCM_BOOL_F
));
761 SCM_DEFINE (scm_struct_vtable_name
, "struct-vtable-name", 1, 0, 0,
763 "Return the name of the vtable @var{vtable}.")
764 #define FUNC_NAME s_scm_struct_vtable_name
766 SCM_VALIDATE_VTABLE (1,vtable
);
767 return SCM_STRUCT_TABLE_NAME (SCM_CDR (scm_struct_create_handle (vtable
)));
771 SCM_DEFINE (scm_set_struct_vtable_name_x
, "set-struct-vtable-name!", 2, 0, 0,
772 (SCM vtable
, SCM name
),
773 "Set the name of the vtable @var{vtable} to @var{name}.")
774 #define FUNC_NAME s_scm_set_struct_vtable_name_x
776 SCM_VALIDATE_VTABLE (1,vtable
);
777 SCM_VALIDATE_SYMBOL (2,name
);
778 SCM_SET_STRUCT_TABLE_NAME (SCM_CDR (scm_struct_create_handle (vtable
)),
780 return SCM_UNSPECIFIED
;
788 scm_print_struct (SCM exp
, SCM port
, scm_print_state
*pstate
)
790 if (SCM_NFALSEP (scm_procedure_p (SCM_STRUCT_PRINTER (exp
))))
791 scm_printer_apply (SCM_STRUCT_PRINTER (exp
), exp
, port
, pstate
);
794 SCM vtable
= SCM_STRUCT_VTABLE (exp
);
795 SCM name
= scm_struct_vtable_name (vtable
);
796 scm_puts ("#<", port
);
797 if (SCM_NFALSEP (name
))
798 scm_display (name
, port
);
800 scm_puts ("struct", port
);
801 scm_putc (' ', port
);
802 scm_intprint (SCM_UNPACK (vtable
), 16, port
);
803 scm_putc (':', port
);
804 scm_intprint (SCM_UNPACK (exp
), 16, port
);
805 scm_putc ('>', port
);
810 scm_struct_prehistory ()
812 scm_c_hook_add (&scm_before_mark_c_hook
, scm_struct_gc_init
, 0, 0);
813 scm_c_hook_add (&scm_after_sweep_c_hook
, scm_free_structs
, 0, 0);
820 = scm_permanent_object (scm_make_weak_key_hash_table (SCM_MAKINUM (31)));
821 required_vtable_fields
= scm_makfrom0str ("pruosrpw");
822 scm_permanent_object (required_vtable_fields
);
823 scm_sysintern ("vtable-index-layout", SCM_MAKINUM (scm_vtable_index_layout
));
824 scm_sysintern ("vtable-index-vtable", SCM_MAKINUM (scm_vtable_index_vtable
));
825 scm_sysintern ("vtable-index-printer", SCM_MAKINUM (scm_vtable_index_printer
));
826 scm_sysintern ("vtable-offset-user", SCM_MAKINUM (scm_vtable_offset_user
));
827 #ifndef SCM_MAGIC_SNARFER
828 #include "libguile/struct.x"