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/* Copyright (C) 1996,1999,2000,2001, 2003, 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.c 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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* {Objects and structs}
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* Objects are currently based upon structs. Although the struct
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* implementation will change thoroughly in the future, objects will
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* still be based upon structs.
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#include "libguile/__scm.h"
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#include "libguile/struct.h"
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* These are used for efficient identification of instances of a
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* certain class or its subclasses when traversal of the inheritance
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* graph would be too costly.
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#define SCM_CLASS_FLAGS(class) (SCM_STRUCT_DATA (class) [scm_struct_i_flags])
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#define SCM_OBJ_CLASS_FLAGS(obj) (SCM_STRUCT_VTABLE_DATA (obj) [scm_struct_i_flags])
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#define SCM_SET_CLASS_FLAGS(c, f) (SCM_CLASS_FLAGS (c) |= (f))
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#define SCM_CLEAR_CLASS_FLAGS(c, f) (SCM_CLASS_FLAGS (c) &= ~(f))
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#define SCM_CLASSF_MASK SCM_STRUCTF_MASK
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#define SCM_CLASSF_ENTITY SCM_STRUCTF_ENTITY
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/* Operator classes need to be identified in the evaluator.
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(Entities also have SCM_CLASSF_OPERATOR set in their vtable.) */
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#define SCM_CLASSF_OPERATOR (1L << 29)
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#define SCM_I_OPERATORP(obj)\
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((SCM_OBJ_CLASS_FLAGS (obj) & SCM_CLASSF_OPERATOR) != 0)
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#define SCM_OPERATOR_CLASS(obj)\
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((struct scm_metaclass_operator *) SCM_STRUCT_DATA (obj))
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#define SCM_OBJ_OPERATOR_CLASS(obj)\
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((struct scm_metaclass_operator *) SCM_STRUCT_VTABLE_DATA (obj))
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#define SCM_OPERATOR_PROCEDURE(obj) (SCM_OBJ_OPERATOR_CLASS (obj)->procedure)
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#define SCM_OPERATOR_SETTER(obj) (SCM_OBJ_OPERATOR_CLASS (obj)->setter)
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#define SCM_I_ENTITYP(obj)\
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((SCM_OBJ_CLASS_FLAGS (obj) & SCM_CLASSF_ENTITY) != 0)
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#define SCM_ENTITY_PROCEDURE(obj) \
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(SCM_PACK (SCM_STRUCT_DATA (obj) [scm_struct_i_procedure]))
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#define SCM_SET_ENTITY_PROCEDURE(obj, v) \
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(SCM_STRUCT_DATA (obj) [scm_struct_i_procedure] = SCM_UNPACK (v))
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#define SCM_ENTITY_SETTER(obj) (SCM_PACK (SCM_STRUCT_DATA (obj)[scm_struct_i_setter]))
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#define SCM_SET_ENTITY_SETTER(obj, v) \
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(SCM_STRUCT_DATA (obj) [scm_struct_i_setter] = SCM_UNPACK (v))
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#define SCM_SET_CLASS_DESTRUCTOR(c, d) SCM_SET_VTABLE_DESTRUCTOR (c, d)
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#define SCM_SET_CLASS_INSTANCE_SIZE(c, s) \
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(SCM_STRUCT_DATA (c)[scm_struct_i_size] \
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= (SCM_STRUCT_DATA (c) [scm_struct_i_size] & SCM_STRUCTF_MASK) | s)
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* Instances of operator classes can work as operators, i. e., they
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* can be applied to arguments just as if they were ordinary
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* For instances of operator classes, the procedures to be applied are
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* stored in four dedicated slots in the associated class object.
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* Which one is selected depends on the number of arguments in the
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* If zero arguments are passed, the first will be selected.
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* If one argument is passed, the second will be selected.
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* If two arguments are passed, the third will be selected.
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* If three or more arguments are passed, the fourth will be selected.
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* This is complicated and may seem gratuitous but has to do with the
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* architecture of the evaluator. Using only one procedure would
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* result in a great deal less efficient application, loss of
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* tail-recursion and would be difficult to reconcile with the
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* debugging evaluator.
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* Also, using this "forked" application in low-level code has the
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* advantage of speeding up some code. An example is method dispatch
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* for generic operators applied to few arguments. On the user level,
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* the "forked" application will be hidden by mechanisms in the GOOPS
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* Operator classes have the metaclass <operator-metaclass>.
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* An example of an operator class is the class <tk-command>.
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#define SCM_METACLASS_STANDARD_LAYOUT ""
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struct scm_metaclass_standard {
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#define SCM_METACLASS_OPERATOR_LAYOUT "popo"
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struct scm_metaclass_operator {
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* For instances of entity classes (entities), the procedures to be
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* applied are stored in the instance itself rather than in the class
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* object as is the case for instances of operator classes (see above).
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* An example of an entity class is the class of generic methods.
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#define SCM_ENTITY_LAYOUT ""
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/* {Interface to Goops}
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* The evaluator contains a multi-method dispatch mechanism.
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* This interface is used by that mechanism and during creation of
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* smob and struct classes.
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/* Internal representation of Goops objects. */
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#define SCM_CLASSF_PURE_GENERIC (0x010 << 20)
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#define SCM_CLASSF_GOOPS_VALID (0x080 << 20)
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#define SCM_CLASSF_GOOPS (0x100 << 20)
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#define scm_si_redefined 5
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#define scm_si_hashsets 6
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#define SCM_CLASS_OF(x) SCM_STRUCT_VTABLE (x)
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#define SCM_OBJ_CLASS_REDEF(x) (SCM_PACK (SCM_STRUCT_VTABLE_DATA (x) [scm_si_redefined]))
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typedef struct scm_effective_slot_definition {
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SCM (*get) (SCM obj, SCM slotdef);
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SCM (*set) (SCM obj, SCM slotdef, SCM value);
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} scm_effective_slot_definition;
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#define SCM_ESLOTDEF(x) ((scm_effective_slot_definition *) SCM_CDR (x))
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#define SCM_CMETHOD_CODE(cmethod) SCM_CDR (cmethod)
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#define SCM_CMETHOD_FORMALS(cmethod) SCM_CAR (SCM_CMETHOD_CODE (cmethod))
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#define SCM_CMETHOD_BODY(cmethod) SCM_CDR (SCM_CMETHOD_CODE (cmethod))
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#define SCM_CMETHOD_ENV(cmethod) SCM_CAR (cmethod)
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#define SCM_IN_PCLASS_INDEX 0x000
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#define SCM_OUT_PCLASS_INDEX 0x100
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#define SCM_INOUT_PCLASS_INDEX 0x200
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/* Plugin proxy classes for basic types. */
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SCM_API SCM scm_metaclass_standard;
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SCM_API SCM scm_metaclass_operator;
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/* Goops functions. */
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SCM_API SCM scm_make_extended_class (char const *type_name, int applicablep);
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SCM_API void scm_i_inherit_applicable (SCM c);
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SCM_API void scm_make_port_classes (long ptobnum, char *type_name);
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SCM_API void scm_change_object_class (SCM, SCM, SCM);
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SCM_API SCM scm_memoize_method (SCM x, SCM args);
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SCM_API SCM scm_mcache_lookup_cmethod (SCM cache, SCM args);
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SCM_API SCM scm_mcache_compute_cmethod (SCM cache, SCM args);
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/* The following are declared in __scm.h
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SCM_API SCM scm_call_generic_0 (SCM gf);
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SCM_API SCM scm_call_generic_1 (SCM gf, SCM a1);
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SCM_API SCM scm_call_generic_2 (SCM gf, SCM a1, SCM a2);
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SCM_API SCM scm_apply_generic (SCM gf, SCM args);
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SCM_API SCM scm_call_generic_3 (SCM gf, SCM a1, SCM a2, SCM a3);
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SCM_API SCM scm_entity_p (SCM obj);
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SCM_API SCM scm_operator_p (SCM obj);
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SCM_API SCM scm_valid_object_procedure_p (SCM proc);
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SCM_API SCM scm_set_object_procedure_x (SCM obj, SCM proc);
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SCM_API SCM scm_object_procedure (SCM obj);
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SCM_API SCM scm_make_class_object (SCM metaclass, SCM layout);
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SCM_API SCM scm_make_subclass_object (SCM c, SCM layout);
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SCM_API SCM scm_i_make_class_object (SCM metaclass, SCM layout_string,
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unsigned long flags);
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SCM_API void scm_init_objects (void);
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#endif /* SCM_OBJECTS_H */
added
removed
libguile/objects.h
