1 /* Copyright (C) 1996,1997,1998,1999,2000,2001, 2003, 2004, 2006 Free Software Foundation, Inc.
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public
5 * License as published by the Free Software Foundation; either
6 * version 2.1 of the License, or (at your option) any later version.
8 * This library 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 GNU
11 * Lesser General Public License for more details.
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libguile/_scm.h"
24 #include "libguile/async.h"
25 #include "libguile/chars.h"
26 #include "libguile/eval.h"
27 #include "libguile/alist.h"
28 #include "libguile/weaks.h"
29 #include "libguile/hashtab.h"
30 #include "libguile/ports.h"
31 #include "libguile/strings.h"
33 #include "libguile/validate.h"
34 #include "libguile/struct.h"
36 #include "libguile/eq.h"
42 #include "libguile/boehm-gc.h"
46 static SCM required_vtable_fields
= SCM_BOOL_F
;
50 SCM_DEFINE (scm_make_struct_layout
, "make-struct-layout", 1, 0, 0,
52 "Return a new structure layout object.\n\n"
53 "@var{fields} must be a string made up of pairs of characters\n"
54 "strung together. The first character of each pair describes a field\n"
55 "type, the second a field protection. Allowed types are 'p' for\n"
56 "GC-protected Scheme data, 'u' for unprotected binary data, and 's' for\n"
57 "a field that points to the structure itself. Allowed protections\n"
58 "are 'w' for mutable fields, 'r' for read-only fields, and 'o' for opaque\n"
59 "fields. The last field protection specification may be capitalized to\n"
60 "indicate that the field is a tail-array.")
61 #define FUNC_NAME s_scm_make_struct_layout
64 SCM_VALIDATE_STRING (1, fields
);
67 const char * field_desc
;
71 len
= scm_i_string_length (fields
);
73 SCM_MISC_ERROR ("odd length field specification: ~S",
76 field_desc
= scm_i_string_chars (fields
);
78 for (x
= 0; x
< len
; x
+= 2)
80 switch (field_desc
[x
])
91 SCM_MISC_ERROR ("unrecognized field type: ~S",
92 scm_list_1 (SCM_MAKE_CHAR (field_desc
[x
])));
95 switch (field_desc
[x
+ 1])
98 if (field_desc
[x
] == 's')
99 SCM_MISC_ERROR ("self fields not writable", SCM_EOL
);
106 if (field_desc
[x
] == 's')
107 SCM_MISC_ERROR ("self fields not allowed in tail array",
110 SCM_MISC_ERROR ("tail array field must be last field in layout",
114 SCM_MISC_ERROR ("unrecognized ref specification: ~S",
115 scm_list_1 (SCM_MAKE_CHAR (field_desc
[x
+ 1])));
118 if (field_desc
[x
] == 'd')
120 if (field_desc
[x
+ 2] != '-')
121 SCM_MISC_ERROR ("missing dash field at position ~A",
122 scm_list_1 (scm_from_int (x
/ 2)));
128 new_sym
= scm_string_to_symbol (fields
);
130 scm_remember_upto_here_1 (fields
);
140 scm_struct_init (SCM handle
, SCM layout
, scm_t_bits
* mem
, int tail_elts
, SCM inits
)
142 unsigned const char *fields_desc
=
143 (unsigned const char *) scm_i_symbol_chars (layout
) - 2;
144 unsigned char prot
= 0;
145 int n_fields
= scm_i_symbol_length (layout
) / 2;
153 prot
= fields_desc
[1];
154 if (SCM_LAYOUT_TAILP (prot
))
157 prot
= prot
== 'R' ? 'r' : prot
== 'W' ? 'w' : 'o';
159 n_fields
+= tail_elts
- 1;
165 switch (*fields_desc
)
169 if ((prot
!= 'r' && prot
!= 'w') || inits
== SCM_EOL
)
173 *mem
= scm_to_long (SCM_CAR (inits
));
174 inits
= SCM_CDR (inits
);
180 if ((prot
!= 'r' && prot
!= 'w') || scm_is_null (inits
))
184 *mem
= scm_to_ulong (SCM_CAR (inits
));
185 inits
= SCM_CDR (inits
);
190 if ((prot
!= 'r' && prot
!= 'w') || scm_is_null (inits
))
191 *mem
= SCM_UNPACK (SCM_BOOL_F
);
194 *mem
= SCM_UNPACK (SCM_CAR (inits
));
195 inits
= SCM_CDR (inits
);
202 if ((prot
!= 'r' && prot
!= 'w') || inits
== SCM_EOL
)
203 *((double *)mem
) = 0.0;
206 *mem
= scm_num2dbl (SCM_CAR (inits
), "scm_struct_init");
207 inits
= SCM_CDR (inits
);
214 *mem
= SCM_UNPACK (handle
);
224 SCM_DEFINE (scm_struct_p
, "struct?", 1, 0, 0,
226 "Return @code{#t} iff @var{x} is a structure object, else\n"
228 #define FUNC_NAME s_scm_struct_p
230 return scm_from_bool(SCM_STRUCTP (x
));
234 SCM_DEFINE (scm_struct_vtable_p
, "struct-vtable?", 1, 0, 0,
236 "Return @code{#t} iff @var{x} is a vtable structure.")
237 #define FUNC_NAME s_scm_struct_vtable_p
243 if (!SCM_STRUCTP (x
))
246 layout
= SCM_STRUCT_LAYOUT (x
);
248 if (scm_i_symbol_length (layout
)
249 < scm_i_string_length (required_vtable_fields
))
252 tmp
= strncmp (scm_i_symbol_chars (layout
),
253 scm_i_string_chars (required_vtable_fields
),
254 scm_i_string_length (required_vtable_fields
));
255 scm_remember_upto_here_1 (required_vtable_fields
);
259 mem
= SCM_STRUCT_DATA (x
);
261 return scm_from_bool (scm_is_symbol (SCM_PACK (mem
[scm_vtable_index_layout
])));
266 /* All struct data must be allocated at an address whose bottom three
267 bits are zero. This is because the tag for a struct lives in the
268 bottom three bits of the struct's car, and the upper bits point to
269 the data of its vtable, which is a struct itself. Thus, if the
270 address of that data doesn't end in three zeros, tagging it will
273 This function allocates a block of memory, and returns a pointer at
274 least scm_struct_n_extra_words words into the block. Furthermore,
275 it guarantees that that pointer's least three significant bits are
278 The argument n_words should be the number of words that should
279 appear after the returned address. (That is, it shouldn't include
280 scm_struct_n_extra_words.)
282 This function initializes the following fields of the struct:
284 scm_struct_i_ptr --- the actual start of the block of memory; the
285 address you should pass to 'free' to dispose of the block.
286 This field allows us to both guarantee that the returned
287 address is divisible by eight, and allow the GC to free the
290 scm_struct_i_n_words --- the number of words allocated to the
291 block, including the extra fields. This is used by the GC.
297 scm_alloc_struct (int n_words
, int n_extra
, const char *what
)
299 int size
= sizeof (scm_t_bits
) * (n_words
+ n_extra
) + 7;
300 void * block
= scm_gc_malloc (size
, what
);
302 /* Adjust the pointer to hide the extra words. */
303 scm_t_bits
* p
= (scm_t_bits
*) block
+ n_extra
;
305 /* Adjust it even further so it's aligned on an eight-byte boundary. */
306 p
= (scm_t_bits
*) (((scm_t_bits
) p
+ 7) & ~7);
308 /* Initialize a few fields as described above. */
309 p
[scm_struct_i_free
] = (scm_t_bits
) 0;
310 p
[scm_struct_i_ptr
] = (scm_t_bits
) block
;
311 p
[scm_struct_i_n_words
] = n_words
;
312 p
[scm_struct_i_flags
] = 0;
314 /* Since `SCM' objects will record either P or P + SCM_TC3_STRUCT, we need
315 to register them as valid displacements. Fortunately, only a handful of
316 N_EXTRA values are used in core Guile. */
317 GC_REGISTER_DISPLACEMENT ((char *)p
- (char *)block
);
318 GC_REGISTER_DISPLACEMENT ((char *)p
- (char *)block
+ scm_tc3_struct
);
327 /* Invoke the finalizer of the struct pointed to by PTR. */
329 struct_finalizer_trampoline (GC_PTR ptr
, GC_PTR unused_data
)
331 SCM obj
= PTR2SCM (ptr
);
333 /* XXX - use less explicit code. */
334 scm_t_bits word0
= SCM_CELL_WORD_0 (obj
) - scm_tc3_struct
;
335 scm_t_bits
*vtable_data
= (scm_t_bits
*) word0
;
336 scm_t_bits
*data
= SCM_STRUCT_DATA (obj
);
337 scm_t_struct_free free_struct_data
338 = ((scm_t_struct_free
) vtable_data
[scm_struct_i_free
]);
340 SCM_SET_CELL_TYPE (obj
, scm_tc_free_cell
);
343 /* A sanity check. However, this check can fail if the free function
344 changed between the `make-struct' time and now. */
345 if (free_struct_data
!= (scm_t_struct_free
)unused_data
)
349 if (free_struct_data
)
350 free_struct_data (vtable_data
, data
);
356 SCM_DEFINE (scm_make_struct
, "make-struct", 2, 0, 1,
357 (SCM vtable
, SCM tail_array_size
, SCM init
),
358 "Create a new structure.\n\n"
359 "@var{type} must be a vtable structure (@pxref{Vtables}).\n\n"
360 "@var{tail-elts} must be a non-negative integer. If the layout\n"
361 "specification indicated by @var{type} includes a tail-array,\n"
362 "this is the number of elements allocated to that array.\n\n"
363 "The @var{init1}, @dots{} are optional arguments describing how\n"
364 "successive fields of the structure should be initialized. Only fields\n"
365 "with protection 'r' or 'w' can be initialized, except for fields of\n"
366 "type 's', which are automatically initialized to point to the new\n"
367 "structure itself; fields with protection 'o' can not be initialized by\n"
368 "Scheme programs.\n\n"
369 "If fewer optional arguments than initializable fields are supplied,\n"
370 "fields of type 'p' get default value #f while fields of type 'u' are\n"
371 "initialized to 0.\n\n"
372 "Structs are currently the basic representation for record-like data\n"
373 "structures in Guile. The plan is to eventually replace them with a\n"
374 "new representation which will at the same time be easier to use and\n"
376 "For more information, see the documentation for @code{make-vtable-vtable}.")
377 #define FUNC_NAME s_scm_make_struct
382 scm_t_bits
*data
, *c_vtable
;
385 SCM_VALIDATE_VTABLE (1, vtable
);
386 SCM_VALIDATE_REST_ARGUMENT (init
);
388 c_vtable
= SCM_STRUCT_DATA (vtable
);
390 layout
= SCM_PACK (c_vtable
[scm_vtable_index_layout
]);
391 basic_size
= scm_i_symbol_length (layout
) / 2;
392 tail_elts
= scm_to_size_t (tail_array_size
);
393 SCM_CRITICAL_SECTION_START
;
394 if (c_vtable
[scm_struct_i_flags
] & SCM_STRUCTF_ENTITY
)
396 data
= scm_alloc_struct (basic_size
+ tail_elts
,
397 scm_struct_entity_n_extra_words
,
399 data
[scm_struct_i_procedure
] = SCM_UNPACK (SCM_BOOL_F
);
400 data
[scm_struct_i_setter
] = SCM_UNPACK (SCM_BOOL_F
);
403 data
= scm_alloc_struct (basic_size
+ tail_elts
,
404 scm_struct_n_extra_words
,
406 handle
= scm_double_cell ((((scm_t_bits
) c_vtable
)
408 (scm_t_bits
) data
, 0, 0);
409 scm_struct_init (handle
, layout
, data
, tail_elts
, init
);
411 if (c_vtable
[scm_struct_i_free
])
413 /* Register a finalizer for the newly created instance. */
414 GC_finalization_proc prev_finalizer
;
415 GC_PTR prev_finalizer_data
;
416 scm_t_struct_free free_struct
=
417 (scm_t_struct_free
)c_vtable
[scm_struct_i_free
];
419 GC_REGISTER_FINALIZER_NO_ORDER (SCM2PTR (handle
),
420 struct_finalizer_trampoline
,
423 &prev_finalizer_data
);
426 SCM_CRITICAL_SECTION_END
;
433 SCM_DEFINE (scm_make_vtable_vtable
, "make-vtable-vtable", 2, 0, 1,
434 (SCM user_fields
, SCM tail_array_size
, SCM init
),
435 "Return a new, self-describing vtable structure.\n\n"
436 "@var{user-fields} is a string describing user defined fields of the\n"
437 "vtable beginning at index @code{vtable-offset-user}\n"
438 "(see @code{make-struct-layout}).\n\n"
439 "@var{tail-size} specifies the size of the tail-array (if any) of\n"
441 "@var{init1}, @dots{} are the optional initializers for the fields of\n"
443 "Vtables have one initializable system field---the struct printer.\n"
444 "This field comes before the user fields in the initializers passed\n"
445 "to @code{make-vtable-vtable} and @code{make-struct}, and thus works as\n"
446 "a third optional argument to @code{make-vtable-vtable} and a fourth to\n"
447 "@code{make-struct} when creating vtables:\n\n"
448 "If the value is a procedure, it will be called instead of the standard\n"
449 "printer whenever a struct described by this vtable is printed.\n"
450 "The procedure will be called with arguments STRUCT and PORT.\n\n"
451 "The structure of a struct is described by a vtable, so the vtable is\n"
452 "in essence the type of the struct. The vtable is itself a struct with\n"
453 "a vtable. This could go on forever if it weren't for the\n"
454 "vtable-vtables which are self-describing vtables, and thus terminate\n"
456 "There are several potential ways of using structs, but the standard\n"
457 "one is to use three kinds of structs, together building up a type\n"
458 "sub-system: one vtable-vtable working as the root and one or several\n"
459 "\"types\", each with a set of \"instances\". (The vtable-vtable should be\n"
460 "compared to the class <class> which is the class of itself.)\n\n"
462 "(define ball-root (make-vtable-vtable \"pr\" 0))\n\n"
463 "(define (make-ball-type ball-color)\n"
464 " (make-struct ball-root 0\n"
465 " (make-struct-layout \"pw\")\n"
466 " (lambda (ball port)\n"
467 " (format port \"#<a ~A ball owned by ~A>\"\n"
471 "(define (color ball) (struct-ref (struct-vtable ball) vtable-offset-user))\n"
472 "(define (owner ball) (struct-ref ball 0))\n\n"
473 "(define red (make-ball-type 'red))\n"
474 "(define green (make-ball-type 'green))\n\n"
475 "(define (make-ball type owner) (make-struct type 0 owner))\n\n"
476 "(define ball (make-ball green 'Nisse))\n"
477 "ball @result{} #<a green ball owned by Nisse>\n"
479 #define FUNC_NAME s_scm_make_vtable_vtable
488 SCM_VALIDATE_STRING (1, user_fields
);
489 SCM_VALIDATE_REST_ARGUMENT (init
);
491 fields
= scm_string_append (scm_list_2 (required_vtable_fields
,
493 layout
= scm_make_struct_layout (fields
);
494 basic_size
= scm_i_symbol_length (layout
) / 2;
495 tail_elts
= scm_to_size_t (tail_array_size
);
496 SCM_CRITICAL_SECTION_START
;
497 data
= scm_alloc_struct (basic_size
+ tail_elts
,
498 scm_struct_n_extra_words
,
500 handle
= scm_double_cell ((scm_t_bits
) data
+ scm_tc3_struct
,
501 (scm_t_bits
) data
, 0, 0);
502 data
[scm_vtable_index_layout
] = SCM_UNPACK (layout
);
503 scm_struct_init (handle
, layout
, data
, tail_elts
, scm_cons (layout
, init
));
504 SCM_CRITICAL_SECTION_END
;
510 /* Return true if S1 and S2 are equal structures, i.e., if their vtable and
511 contents are the same. Field protections are honored. Thus, it is an
512 error to test the equality of structures that contain opaque fields. */
514 scm_i_struct_equalp (SCM s1
, SCM s2
)
515 #define FUNC_NAME "scm_i_struct_equalp"
517 SCM vtable1
, vtable2
, layout
;
518 size_t struct_size
, field_num
;
520 SCM_VALIDATE_STRUCT (1, s1
);
521 SCM_VALIDATE_STRUCT (2, s2
);
523 vtable1
= SCM_STRUCT_VTABLE (s1
);
524 vtable2
= SCM_STRUCT_VTABLE (s2
);
526 if (!scm_is_eq (vtable1
, vtable2
))
529 layout
= SCM_STRUCT_LAYOUT (s1
);
530 struct_size
= scm_i_symbol_length (layout
) / 2;
532 for (field_num
= 0; field_num
< struct_size
; field_num
++)
537 /* We have to use `scm_struct_ref ()' here so that fields are accessed
538 consistently, notably wrt. field types and access rights. */
539 s_field_num
= scm_from_size_t (field_num
);
540 field1
= scm_struct_ref (s1
, s_field_num
);
541 field2
= scm_struct_ref (s2
, s_field_num
);
543 if (scm_is_false (scm_equal_p (field1
, field2
)))
555 SCM_DEFINE (scm_struct_ref
, "struct-ref", 2, 0, 0,
556 (SCM handle
, SCM pos
),
557 "@deffnx {Scheme Procedure} struct-set! struct n value\n"
558 "Access (or modify) the @var{n}th field of @var{struct}.\n\n"
559 "If the field is of type 'p', then it can be set to an arbitrary value.\n\n"
560 "If the field is of type 'u', then it can only be set to a non-negative\n"
561 "integer value small enough to fit in one machine word.")
562 #define FUNC_NAME s_scm_struct_ref
564 SCM answer
= SCM_UNDEFINED
;
570 const char *fields_desc
;
574 SCM_VALIDATE_STRUCT (1, handle
);
576 layout
= SCM_STRUCT_LAYOUT (handle
);
577 data
= SCM_STRUCT_DATA (handle
);
578 p
= scm_to_size_t (pos
);
580 fields_desc
= scm_i_symbol_chars (layout
);
581 layout_len
= scm_i_symbol_length (layout
);
582 n_fields
= data
[scm_struct_i_n_words
];
584 SCM_ASSERT_RANGE(1, pos
, p
< n_fields
);
586 if (p
* 2 < layout_len
)
589 field_type
= fields_desc
[p
* 2];
590 ref
= fields_desc
[p
* 2 + 1];
591 if ((ref
!= 'r') && (ref
!= 'w'))
593 if ((ref
== 'R') || (ref
== 'W'))
596 SCM_MISC_ERROR ("ref denied for field ~A", scm_list_1 (pos
));
599 else if (fields_desc
[layout_len
- 1] != 'O')
600 field_type
= fields_desc
[layout_len
- 2];
602 SCM_MISC_ERROR ("ref denied for field ~A", scm_list_1 (pos
));
607 answer
= scm_from_ulong (data
[p
]);
612 answer
= scm_from_long (data
[p
]);
616 answer
= scm_make_real (*((double *)&(data
[p
])));
622 answer
= SCM_PACK (data
[p
]);
627 SCM_MISC_ERROR ("unrecognized field type: ~S",
628 scm_list_1 (SCM_MAKE_CHAR (field_type
)));
636 SCM_DEFINE (scm_struct_set_x
, "struct-set!", 3, 0, 0,
637 (SCM handle
, SCM pos
, SCM val
),
638 "Set the slot of the structure @var{handle} with index @var{pos}\n"
639 "to @var{val}. Signal an error if the slot can not be written\n"
641 #define FUNC_NAME s_scm_struct_set_x
648 const char *fields_desc
;
651 SCM_VALIDATE_STRUCT (1, handle
);
653 layout
= SCM_STRUCT_LAYOUT (handle
);
654 data
= SCM_STRUCT_DATA (handle
);
655 p
= scm_to_size_t (pos
);
657 fields_desc
= scm_i_symbol_chars (layout
);
658 layout_len
= scm_i_symbol_length (layout
);
659 n_fields
= data
[scm_struct_i_n_words
];
661 SCM_ASSERT_RANGE (1, pos
, p
< n_fields
);
663 if (p
* 2 < layout_len
)
666 field_type
= fields_desc
[p
* 2];
667 set_x
= fields_desc
[p
* 2 + 1];
669 SCM_MISC_ERROR ("set! denied for field ~A", scm_list_1 (pos
));
671 else if (fields_desc
[layout_len
- 1] == 'W')
672 field_type
= fields_desc
[layout_len
- 2];
674 SCM_MISC_ERROR ("set! denied for field ~A", scm_list_1 (pos
));
679 data
[p
] = SCM_NUM2ULONG (3, val
);
684 data
[p
] = SCM_NUM2LONG (3, val
);
688 *((double *)&(data
[p
])) = scm_num2dbl (val
, (char *)SCM_ARG3
);
693 data
[p
] = SCM_UNPACK (val
);
697 SCM_MISC_ERROR ("self fields immutable", SCM_EOL
);
700 SCM_MISC_ERROR ("unrecognized field type: ~S",
701 scm_list_1 (SCM_MAKE_CHAR (field_type
)));
709 SCM_DEFINE (scm_struct_vtable
, "struct-vtable", 1, 0, 0,
711 "Return the vtable structure that describes the type of @var{struct}.")
712 #define FUNC_NAME s_scm_struct_vtable
714 SCM_VALIDATE_STRUCT (1, handle
);
715 return SCM_STRUCT_VTABLE (handle
);
720 SCM_DEFINE (scm_struct_vtable_tag
, "struct-vtable-tag", 1, 0, 0,
722 "Return the vtable tag of the structure @var{handle}.")
723 #define FUNC_NAME s_scm_struct_vtable_tag
725 SCM_VALIDATE_VTABLE (1, handle
);
726 return scm_from_ulong (((unsigned long)SCM_STRUCT_DATA (handle
)) >> 3);
730 /* {Associating names and classes with vtables}
732 * The name of a vtable should probably be stored as a slot. This is
733 * a backward compatible solution until agreement has been achieved on
734 * how to associate names with vtables.
738 scm_struct_ihashq (SCM obj
, unsigned long n
)
740 /* The length of the hash table should be a relative prime it's not
741 necessary to shift down the address. */
742 return SCM_UNPACK (obj
) % n
;
746 scm_struct_create_handle (SCM obj
)
748 SCM handle
= scm_hash_fn_create_handle_x (scm_struct_table
,
754 if (scm_is_false (SCM_CDR (handle
)))
755 SCM_SETCDR (handle
, scm_cons (SCM_BOOL_F
, SCM_BOOL_F
));
759 SCM_DEFINE (scm_struct_vtable_name
, "struct-vtable-name", 1, 0, 0,
761 "Return the name of the vtable @var{vtable}.")
762 #define FUNC_NAME s_scm_struct_vtable_name
764 SCM_VALIDATE_VTABLE (1, vtable
);
765 return SCM_STRUCT_TABLE_NAME (SCM_CDR (scm_struct_create_handle (vtable
)));
769 SCM_DEFINE (scm_set_struct_vtable_name_x
, "set-struct-vtable-name!", 2, 0, 0,
770 (SCM vtable
, SCM name
),
771 "Set the name of the vtable @var{vtable} to @var{name}.")
772 #define FUNC_NAME s_scm_set_struct_vtable_name_x
774 SCM_VALIDATE_VTABLE (1, vtable
);
775 SCM_VALIDATE_SYMBOL (2, name
);
776 SCM_SET_STRUCT_TABLE_NAME (SCM_CDR (scm_struct_create_handle (vtable
)),
778 return SCM_UNSPECIFIED
;
786 scm_print_struct (SCM exp
, SCM port
, scm_print_state
*pstate
)
788 if (scm_is_true (scm_procedure_p (SCM_STRUCT_PRINTER (exp
))))
789 scm_printer_apply (SCM_STRUCT_PRINTER (exp
), exp
, port
, pstate
);
792 SCM vtable
= SCM_STRUCT_VTABLE (exp
);
793 SCM name
= scm_struct_vtable_name (vtable
);
794 scm_puts ("#<", port
);
795 if (scm_is_true (name
))
796 scm_display (name
, port
);
798 scm_puts ("struct", port
);
799 scm_putc (' ', port
);
800 scm_uintprint (SCM_UNPACK (vtable
), 16, port
);
801 scm_putc (':', port
);
802 scm_uintprint (SCM_UNPACK (exp
), 16, port
);
803 scm_putc ('>', port
);
808 scm_struct_prehistory ()
817 = scm_permanent_object (scm_make_weak_key_hash_table (scm_from_int (31)));
818 required_vtable_fields
= scm_from_locale_string ("prsrpw");
819 scm_permanent_object (required_vtable_fields
);
820 scm_c_define ("vtable-index-layout", scm_from_int (scm_vtable_index_layout
));
821 scm_c_define ("vtable-index-vtable", scm_from_int (scm_vtable_index_vtable
));
822 scm_c_define ("vtable-index-printer",
823 scm_from_int (scm_vtable_index_printer
));
824 scm_c_define ("vtable-offset-user", scm_from_int (scm_vtable_offset_user
));
825 #include "libguile/struct.x"