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/* Copyright (C) 1995,1996,1999,2000,2001, 2003, 2004, 2006 Free Software Foundation, Inc.
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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/* This file and objects.h contains those minimal pieces of the Guile
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* Object Oriented Programming System which need to be included in
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* libguile. See the comments in objects.h.
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#include "libguile/_scm.h"
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#include "libguile/struct.h"
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#include "libguile/procprop.h"
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#include "libguile/chars.h"
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#include "libguile/keywords.h"
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#include "libguile/smob.h"
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#include "libguile/eval.h"
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#include "libguile/alist.h"
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#include "libguile/ports.h"
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#include "libguile/strings.h"
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#include "libguile/vectors.h"
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#include "libguile/validate.h"
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#include "libguile/objects.h"
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#include "libguile/goops.h"
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SCM scm_metaclass_standard;
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SCM scm_metaclass_operator;
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/* The cache argument for scm_mcache_lookup_cmethod has one of two possible
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* (SCM_IM_DISPATCH ARGS N-SPECIALIZED
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* #((TYPE1 ... ENV FORMALS FORM ...) ...)
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* (SCM_IM_HASH_DISPATCH ARGS N-SPECIALIZED HASHSET MASK
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* #((TYPE1 ... ENV FORMALS FORM ...) ...)
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* ARGS is either a list of expressions, in which case they
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* are interpreted as the arguments of an application, or
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* a non-pair, which is interpreted as a single expression
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* yielding all arguments.
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* SCM_IM_DISPATCH expressions in generic functions always
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* have ARGS = the symbol `args' or the iloc #@0-0.
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* Need FORMALS in order to support varying arity. This
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* also avoids the need for renaming of bindings.
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* We should probably not complicate this mechanism by
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* introducing "optimizations" for getters and setters or
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* primitive methods. Getters and setter will normally be
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* compiled into @slot-[ref|set!] or a procedure call.
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* They rely on the dispatch performed before executing
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* the code which contains them.
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* We might want to use a more efficient representation of
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* this form in the future, perhaps after we have introduced
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* low-level support for syntax-case macros.
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scm_mcache_lookup_cmethod (SCM cache, SCM args)
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unsigned long i, mask, n, end;
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SCM ls, methods, z = SCM_CDDR (cache);
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n = scm_to_ulong (SCM_CAR (z)); /* maximum number of specializers */
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methods = SCM_CADR (z);
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if (scm_is_simple_vector (methods))
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/* cache format #1: prepare for linear search */
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end = SCM_SIMPLE_VECTOR_LENGTH (methods);
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/* cache format #2: compute a hash value */
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unsigned long hashset = scm_to_ulong (methods);
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mask = scm_to_ulong (SCM_CAR (z));
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methods = SCM_CADR (z);
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if (!scm_is_null (ls))
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i += SCM_STRUCT_DATA (scm_class_of (SCM_CAR (ls)))
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[scm_si_hashsets + hashset];
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while (j-- && !scm_is_null (ls));
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/* Search for match */
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z = SCM_SIMPLE_VECTOR_REF (methods, i);
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ls = args; /* list of arguments */
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if (!scm_is_null (ls))
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/* More arguments than specifiers => CLASS != ENV */
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if (! scm_is_eq (scm_class_of (SCM_CAR (ls)), SCM_CAR (z)))
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while (j-- && !scm_is_null (ls));
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/* Fewer arguments than specifiers => CAR != ENV */
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if (scm_is_null (SCM_CAR (z)) || scm_is_pair (SCM_CAR (z)))
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scm_mcache_compute_cmethod (SCM cache, SCM args)
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SCM cmethod = scm_mcache_lookup_cmethod (cache, args);
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if (scm_is_false (cmethod))
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/* No match - memoize */
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return scm_memoize_method (cache, args);
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scm_apply_generic (SCM gf, SCM args)
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SCM cmethod = scm_mcache_compute_cmethod (SCM_ENTITY_PROCEDURE (gf), args);
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return scm_eval_body (SCM_CDR (SCM_CMETHOD_CODE (cmethod)),
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SCM_EXTEND_ENV (SCM_CAR (SCM_CMETHOD_CODE (cmethod)),
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SCM_CMETHOD_ENV (cmethod)));
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scm_call_generic_0 (SCM gf)
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return scm_apply_generic (gf, SCM_EOL);
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scm_call_generic_1 (SCM gf, SCM a1)
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return scm_apply_generic (gf, scm_list_1 (a1));
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scm_call_generic_2 (SCM gf, SCM a1, SCM a2)
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return scm_apply_generic (gf, scm_list_2 (a1, a2));
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scm_call_generic_3 (SCM gf, SCM a1, SCM a2, SCM a3)
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return scm_apply_generic (gf, scm_list_3 (a1, a2, a3));
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SCM_DEFINE (scm_entity_p, "entity?", 1, 0, 0,
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"Return @code{#t} if @var{obj} is an entity.")
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#define FUNC_NAME s_scm_entity_p
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return scm_from_bool(SCM_STRUCTP (obj) && SCM_I_ENTITYP (obj));
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SCM_DEFINE (scm_operator_p, "operator?", 1, 0, 0,
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"Return @code{#t} if @var{obj} is an operator.")
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#define FUNC_NAME s_scm_operator_p
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return scm_from_bool(SCM_STRUCTP (obj)
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&& SCM_I_OPERATORP (obj)
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&& !SCM_I_ENTITYP (obj));
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/* XXX - What code requires the object procedure to be only of certain
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SCM_DEFINE (scm_valid_object_procedure_p, "valid-object-procedure?", 1, 0, 0,
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"Return @code{#t} iff @var{proc} is a procedure that can be used "
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"with @code{set-object-procedure}. It is always valid to use "
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"a closure constructed by @code{lambda}.")
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#define FUNC_NAME s_scm_valid_object_procedure_p
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switch (SCM_TYP7 (proc))
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case scm_tcs_closures:
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case scm_tc7_lsubr_2:
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SCM_DEFINE (scm_set_object_procedure_x, "set-object-procedure!", 2, 0, 0,
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"Set the object procedure of @var{obj} to @var{proc}.\n"
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"@var{obj} must be either an entity or an operator.")
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#define FUNC_NAME s_scm_set_object_procedure_x
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SCM_ASSERT (SCM_STRUCTP (obj)
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&& ((SCM_CLASS_FLAGS (obj) & SCM_CLASSF_OPERATOR)
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|| (SCM_I_ENTITYP (obj)
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&& !(SCM_OBJ_CLASS_FLAGS (obj)
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& SCM_CLASSF_PURE_GENERIC))),
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SCM_ASSERT (scm_valid_object_procedure_p (proc), proc, SCM_ARG2, FUNC_NAME);
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if (SCM_I_ENTITYP (obj))
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SCM_SET_ENTITY_PROCEDURE (obj, proc);
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SCM_OPERATOR_CLASS (obj)->procedure = proc;
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return SCM_UNSPECIFIED;
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SCM_DEFINE (scm_object_procedure, "object-procedure", 1, 0, 0,
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"Return the object procedure of @var{obj}. @var{obj} must be\n"
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"an entity or an operator.")
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#define FUNC_NAME s_scm_object_procedure
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SCM_ASSERT (SCM_STRUCTP (obj)
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&& ((SCM_CLASS_FLAGS (obj) & SCM_CLASSF_OPERATOR)
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|| SCM_I_ENTITYP (obj)),
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obj, SCM_ARG1, FUNC_NAME);
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return (SCM_I_ENTITYP (obj)
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? SCM_ENTITY_PROCEDURE (obj)
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: SCM_OPERATOR_CLASS (obj)->procedure);
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#endif /* GUILE_DEBUG */
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/* The following procedures are not a part of Goops but a minimal
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* object system built upon structs. They are here for those who
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* want to implement their own object system.
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scm_i_make_class_object (SCM meta,
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SCM layout = scm_make_struct_layout (layout_string);
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c = scm_make_struct (meta,
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scm_list_4 (layout, SCM_BOOL_F, SCM_EOL, SCM_EOL));
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SCM_SET_CLASS_FLAGS (c, flags);
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SCM_DEFINE (scm_make_class_object, "make-class-object", 2, 0, 0,
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(SCM metaclass, SCM layout),
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"Create a new class object of class @var{metaclass}, with the\n"
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"slot layout specified by @var{layout}.")
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#define FUNC_NAME s_scm_make_class_object
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unsigned long flags = 0;
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SCM_VALIDATE_STRUCT (1, metaclass);
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SCM_VALIDATE_STRING (2, layout);
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if (scm_is_eq (metaclass, scm_metaclass_operator))
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flags = SCM_CLASSF_OPERATOR;
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return scm_i_make_class_object (metaclass, layout, flags);
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SCM_DEFINE (scm_make_subclass_object, "make-subclass-object", 2, 0, 0,
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(SCM class, SCM layout),
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"Create a subclass object of @var{class}, with the slot layout\n"
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"specified by @var{layout}.")
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#define FUNC_NAME s_scm_make_subclass_object
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SCM_VALIDATE_STRUCT (1, class);
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SCM_VALIDATE_STRING (2, layout);
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pl = SCM_PACK (SCM_STRUCT_DATA (class) [scm_vtable_index_layout]);
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pl = scm_symbol_to_string (pl);
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return scm_i_make_class_object (SCM_STRUCT_VTABLE (class),
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scm_string_append (scm_list_2 (pl, layout)),
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SCM_CLASS_FLAGS (class));
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SCM ms = scm_from_locale_string (SCM_METACLASS_STANDARD_LAYOUT);
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SCM mt = scm_make_vtable_vtable (ms, SCM_INUM0,
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scm_list_3 (SCM_BOOL_F, SCM_EOL, SCM_EOL));
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SCM os = scm_from_locale_string (SCM_METACLASS_OPERATOR_LAYOUT);
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SCM ot = scm_make_vtable_vtable (os, SCM_INUM0,
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scm_list_3 (SCM_BOOL_F, SCM_EOL, SCM_EOL));
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SCM es = scm_from_locale_string (SCM_ENTITY_LAYOUT);
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SCM el = scm_make_struct_layout (es);
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SCM et = scm_make_struct (mt, SCM_INUM0,
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scm_list_4 (el, SCM_BOOL_F, SCM_EOL, SCM_EOL));
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scm_c_define ("<class>", mt);
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scm_metaclass_standard = mt;
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scm_c_define ("<operator-class>", ot);
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scm_metaclass_operator = ot;
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SCM_SET_CLASS_FLAGS (et, SCM_CLASSF_OPERATOR | SCM_CLASSF_ENTITY);
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SCM_SET_CLASS_DESTRUCTOR (et, scm_struct_free_entity);
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scm_c_define ("<entity>", et);
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#include "libguile/objects.x"