--- /dev/null
+/* Copyright (C) 1995,1996,1999,2000,2001, 2003, 2004, 2006, 2008 Free Software Foundation, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+
+\f
+
+/* This file and objects.h contains those minimal pieces of the Guile
+ * Object Oriented Programming System which need to be included in
+ * libguile. See the comments in objects.h.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "libguile/_scm.h"
+
+#include "libguile/struct.h"
+#include "libguile/procprop.h"
+#include "libguile/chars.h"
+#include "libguile/keywords.h"
+#include "libguile/smob.h"
+#include "libguile/eval.h"
+#include "libguile/alist.h"
+#include "libguile/ports.h"
+#include "libguile/strings.h"
+#include "libguile/vectors.h"
+
+#include "libguile/validate.h"
+#include "libguile/objects.h"
+#include "libguile/goops.h"
+
+\f
+
+SCM scm_metaclass_standard;
+SCM scm_metaclass_operator;
+
+/* The cache argument for scm_mcache_lookup_cmethod has one of two possible
+ * formats:
+ *
+ * Format #1:
+ * (SCM_IM_DISPATCH ARGS N-SPECIALIZED
+ * #((TYPE1 ... ENV FORMALS FORM ...) ...)
+ * GF)
+ *
+ * Format #2:
+ * (SCM_IM_HASH_DISPATCH ARGS N-SPECIALIZED HASHSET MASK
+ * #((TYPE1 ... ENV FORMALS FORM ...) ...)
+ * GF)
+ *
+ * ARGS is either a list of expressions, in which case they
+ * are interpreted as the arguments of an application, or
+ * a non-pair, which is interpreted as a single expression
+ * yielding all arguments.
+ *
+ * SCM_IM_DISPATCH expressions in generic functions always
+ * have ARGS = the symbol `args' or the iloc #@0-0.
+ *
+ * Need FORMALS in order to support varying arity. This
+ * also avoids the need for renaming of bindings.
+ *
+ * We should probably not complicate this mechanism by
+ * introducing "optimizations" for getters and setters or
+ * primitive methods. Getters and setter will normally be
+ * compiled into @slot-[ref|set!] or a procedure call.
+ * They rely on the dispatch performed before executing
+ * the code which contains them.
+ *
+ * We might want to use a more efficient representation of
+ * this form in the future, perhaps after we have introduced
+ * low-level support for syntax-case macros.
+ */
+
+SCM
+scm_mcache_lookup_cmethod (SCM cache, SCM args)
+{
+ unsigned long i, mask, n, end;
+ SCM ls, methods, z = SCM_CDDR (cache);
+ n = scm_to_ulong (SCM_CAR (z)); /* maximum number of specializers */
+ methods = SCM_CADR (z);
+
+ if (scm_is_simple_vector (methods))
+ {
+ /* cache format #1: prepare for linear search */
+ mask = -1;
+ i = 0;
+ end = SCM_SIMPLE_VECTOR_LENGTH (methods);
+ }
+ else
+ {
+ /* cache format #2: compute a hash value */
+ unsigned long hashset = scm_to_ulong (methods);
+ long j = n;
+ z = SCM_CDDR (z);
+ mask = scm_to_ulong (SCM_CAR (z));
+ methods = SCM_CADR (z);
+ i = 0;
+ ls = args;
+ if (!scm_is_null (ls))
+ do
+ {
+ i += SCM_STRUCT_DATA (scm_class_of (SCM_CAR (ls)))
+ [scm_si_hashsets + hashset];
+ ls = SCM_CDR (ls);
+ }
+ while (j-- && !scm_is_null (ls));
+ i &= mask;
+ end = i;
+ }
+
+ /* Search for match */
+ do
+ {
+ long j = n;
+ z = SCM_SIMPLE_VECTOR_REF (methods, i);
+ ls = args; /* list of arguments */
+ if (!scm_is_null (ls))
+ do
+ {
+ /* More arguments than specifiers => CLASS != ENV */
+ if (! scm_is_eq (scm_class_of (SCM_CAR (ls)), SCM_CAR (z)))
+ goto next_method;
+ ls = SCM_CDR (ls);
+ z = SCM_CDR (z);
+ }
+ while (j-- && !scm_is_null (ls));
+ /* Fewer arguments than specifiers => CAR != ENV */
+ if (scm_is_null (SCM_CAR (z)) || scm_is_pair (SCM_CAR (z)))
+ return z;
+ next_method:
+ i = (i + 1) & mask;
+ } while (i != end);
+ return SCM_BOOL_F;
+}
+
+SCM
+scm_mcache_compute_cmethod (SCM cache, SCM args)
+{
+ SCM cmethod = scm_mcache_lookup_cmethod (cache, args);
+ if (scm_is_false (cmethod))
+ /* No match - memoize */
+ return scm_memoize_method (cache, args);
+ return cmethod;
+}
+
+SCM
+scm_apply_generic (SCM gf, SCM args)
+{
+ SCM cmethod = scm_mcache_compute_cmethod (SCM_ENTITY_PROCEDURE (gf), args);
+ return scm_eval_body (SCM_CDR (SCM_CMETHOD_CODE (cmethod)),
+ SCM_EXTEND_ENV (SCM_CAR (SCM_CMETHOD_CODE (cmethod)),
+ args,
+ SCM_CMETHOD_ENV (cmethod)));
+}
+
+SCM
+scm_call_generic_0 (SCM gf)
+{
+ return scm_apply_generic (gf, SCM_EOL);
+}
+
+SCM
+scm_call_generic_1 (SCM gf, SCM a1)
+{
+ return scm_apply_generic (gf, scm_list_1 (a1));
+}
+
+SCM
+scm_call_generic_2 (SCM gf, SCM a1, SCM a2)
+{
+ return scm_apply_generic (gf, scm_list_2 (a1, a2));
+}
+
+SCM
+scm_call_generic_3 (SCM gf, SCM a1, SCM a2, SCM a3)
+{
+ return scm_apply_generic (gf, scm_list_3 (a1, a2, a3));
+}
+
+SCM_DEFINE (scm_entity_p, "entity?", 1, 0, 0,
+ (SCM obj),
+ "Return @code{#t} if @var{obj} is an entity.")
+#define FUNC_NAME s_scm_entity_p
+{
+ return scm_from_bool(SCM_STRUCTP (obj) && SCM_I_ENTITYP (obj));
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_operator_p, "operator?", 1, 0, 0,
+ (SCM obj),
+ "Return @code{#t} if @var{obj} is an operator.")
+#define FUNC_NAME s_scm_operator_p
+{
+ return scm_from_bool(SCM_STRUCTP (obj)
+ && SCM_I_OPERATORP (obj)
+ && !SCM_I_ENTITYP (obj));
+}
+#undef FUNC_NAME
+
+/* XXX - What code requires the object procedure to be only of certain
+ types? */
+
+SCM_DEFINE (scm_valid_object_procedure_p, "valid-object-procedure?", 1, 0, 0,
+ (SCM proc),
+ "Return @code{#t} iff @var{proc} is a procedure that can be used "
+ "with @code{set-object-procedure}. It is always valid to use "
+ "a closure constructed by @code{lambda}.")
+#define FUNC_NAME s_scm_valid_object_procedure_p
+{
+ if (SCM_IMP (proc))
+ return SCM_BOOL_F;
+ switch (SCM_TYP7 (proc))
+ {
+ default:
+ return SCM_BOOL_F;
+ case scm_tcs_closures:
+ case scm_tc7_subr_1:
+ case scm_tc7_subr_2:
+ case scm_tc7_subr_3:
+ case scm_tc7_lsubr_2:
+ return SCM_BOOL_T;
+ }
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_set_object_procedure_x, "set-object-procedure!", 2, 0, 0,
+ (SCM obj, SCM proc),
+ "Set the object procedure of @var{obj} to @var{proc}.\n"
+ "@var{obj} must be either an entity or an operator.")
+#define FUNC_NAME s_scm_set_object_procedure_x
+{
+ SCM_ASSERT (SCM_STRUCTP (obj)
+ && ((SCM_CLASS_FLAGS (obj) & SCM_CLASSF_OPERATOR)
+ || (SCM_I_ENTITYP (obj)
+ && !(SCM_OBJ_CLASS_FLAGS (obj)
+ & SCM_CLASSF_PURE_GENERIC))),
+ obj,
+ SCM_ARG1,
+ FUNC_NAME);
+ SCM_ASSERT (scm_valid_object_procedure_p (proc), proc, SCM_ARG2, FUNC_NAME);
+ if (SCM_I_ENTITYP (obj))
+ SCM_SET_ENTITY_PROCEDURE (obj, proc);
+ else
+ SCM_OPERATOR_CLASS (obj)->procedure = proc;
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+#ifdef GUILE_DEBUG
+SCM_DEFINE (scm_object_procedure, "object-procedure", 1, 0, 0,
+ (SCM obj),
+ "Return the object procedure of @var{obj}. @var{obj} must be\n"
+ "an entity or an operator.")
+#define FUNC_NAME s_scm_object_procedure
+{
+ SCM_ASSERT (SCM_STRUCTP (obj)
+ && ((SCM_CLASS_FLAGS (obj) & SCM_CLASSF_OPERATOR)
+ || SCM_I_ENTITYP (obj)),
+ obj, SCM_ARG1, FUNC_NAME);
+ return (SCM_I_ENTITYP (obj)
+ ? SCM_ENTITY_PROCEDURE (obj)
+ : SCM_OPERATOR_CLASS (obj)->procedure);
+}
+#undef FUNC_NAME
+#endif /* GUILE_DEBUG */
+
+/* The following procedures are not a part of Goops but a minimal
+ * object system built upon structs. They are here for those who
+ * want to implement their own object system.
+ */
+
+SCM
+scm_i_make_class_object (SCM meta,
+ SCM layout_string,
+ unsigned long flags)
+{
+ SCM c;
+ SCM layout = scm_make_struct_layout (layout_string);
+ c = scm_make_struct (meta,
+ SCM_INUM0,
+ scm_list_4 (layout, SCM_BOOL_F, SCM_EOL, SCM_EOL));
+ SCM_SET_CLASS_FLAGS (c, flags);
+ return c;
+}
+
+SCM_DEFINE (scm_make_class_object, "make-class-object", 2, 0, 0,
+ (SCM metaclass, SCM layout),
+ "Create a new class object of class @var{metaclass}, with the\n"
+ "slot layout specified by @var{layout}.")
+#define FUNC_NAME s_scm_make_class_object
+{
+ unsigned long flags = 0;
+ SCM_VALIDATE_STRUCT (1, metaclass);
+ SCM_VALIDATE_STRING (2, layout);
+ if (scm_is_eq (metaclass, scm_metaclass_operator))
+ flags = SCM_CLASSF_OPERATOR;
+ return scm_i_make_class_object (metaclass, layout, flags);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_make_subclass_object, "make-subclass-object", 2, 0, 0,
+ (SCM class, SCM layout),
+ "Create a subclass object of @var{class}, with the slot layout\n"
+ "specified by @var{layout}.")
+#define FUNC_NAME s_scm_make_subclass_object
+{
+ SCM pl;
+ SCM_VALIDATE_STRUCT (1, class);
+ SCM_VALIDATE_STRING (2, layout);
+ pl = SCM_PACK (SCM_STRUCT_DATA (class) [scm_vtable_index_layout]);
+ pl = scm_symbol_to_string (pl);
+ return scm_i_make_class_object (SCM_STRUCT_VTABLE (class),
+ scm_string_append (scm_list_2 (pl, layout)),
+ SCM_CLASS_FLAGS (class));
+}
+#undef FUNC_NAME
+
+void
+scm_init_objects ()
+{
+ SCM ms = scm_from_locale_string (SCM_METACLASS_STANDARD_LAYOUT);
+ SCM mt = scm_make_vtable_vtable (ms, SCM_INUM0,
+ scm_list_3 (SCM_BOOL_F, SCM_EOL, SCM_EOL));
+
+ SCM os = scm_from_locale_string (SCM_METACLASS_OPERATOR_LAYOUT);
+ SCM ot = scm_make_vtable_vtable (os, SCM_INUM0,
+ scm_list_3 (SCM_BOOL_F, SCM_EOL, SCM_EOL));
+
+ SCM es = scm_from_locale_string (SCM_ENTITY_LAYOUT);
+ SCM el = scm_make_struct_layout (es);
+ SCM et = scm_make_struct (mt, SCM_INUM0,
+ scm_list_4 (el, SCM_BOOL_F, SCM_EOL, SCM_EOL));
+
+ scm_c_define ("<class>", mt);
+ scm_metaclass_standard = mt;
+ scm_c_define ("<operator-class>", ot);
+ scm_metaclass_operator = ot;
+ SCM_SET_CLASS_FLAGS (et, SCM_CLASSF_OPERATOR | SCM_CLASSF_ENTITY);
+ SCM_SET_CLASS_DESTRUCTOR (et, scm_struct_free_entity);
+ scm_c_define ("<entity>", et);
+
+#include "libguile/objects.x"
+}
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/
projects / lilypond.git / blobdiff