[bpt/guile.git] / libguile / objects.c

/*	Copyright (C) 1995, 1996, 1999, 2000 Free Software Foundation, Inc.
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 * 
 * This program 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this software; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307 USA
 *
 * As a special exception, the Free Software Foundation gives permission
 * for additional uses of the text contained in its release of GUILE.
 *
 * The exception is that, if you link the GUILE library with other files
 * to produce an executable, this does not by itself cause the
 * resulting executable to be covered by the GNU General Public License.
 * Your use of that executable is in no way restricted on account of
 * linking the GUILE library code into it.
 *
 * This exception does not however invalidate any other reasons why
 * the executable file might be covered by the GNU General Public License.
 *
 * This exception applies only to the code released by the
 * Free Software Foundation under the name GUILE.  If you copy
 * code from other Free Software Foundation releases into a copy of
 * GUILE, as the General Public License permits, the exception does
 * not apply to the code that you add in this way.  To avoid misleading
 * anyone as to the status of such modified files, you must delete
 * this exception notice from them.
 *
 * If you write modifications of your own for GUILE, it is your choice
 * whether to permit this exception to apply to your modifications.
 * If you do not wish that, delete this exception notice.  */

/* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
   gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */

\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.
 */

#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"
\f

SCM scm_metaclass_standard;
SCM scm_metaclass_operator;

/* These variables are filled in by the object system when loaded. */
SCM scm_class_boolean, scm_class_char, scm_class_pair;
SCM scm_class_procedure, scm_class_string, scm_class_symbol;
SCM scm_class_procedure_with_setter, scm_class_primitive_generic;
SCM scm_class_vector, scm_class_null;
SCM scm_class_integer, scm_class_real, scm_class_complex;
SCM scm_class_unknown;

SCM *scm_port_class = 0;
SCM *scm_smob_class = 0;

SCM scm_no_applicable_method;

/* This function is used for efficient type dispatch.  */
SCM_DEFINE (scm_class_of, "class-of", 1, 0, 0,
	    (SCM x),
	    "Return the class of @var{x}.")
#define FUNC_NAME s_scm_class_of
{
  switch (SCM_ITAG3 (x))
    {
    case scm_tc3_int_1:
    case scm_tc3_int_2:
      return scm_class_integer;

    case scm_tc3_imm24:
      if (SCM_CHARP (x))
	return scm_class_char;
      else
	{
	  switch (SCM_ISYMNUM (x))
	    {
	    case SCM_ISYMNUM (SCM_BOOL_F):
	    case SCM_ISYMNUM (SCM_BOOL_T):
	      return scm_class_boolean;
	    case SCM_ISYMNUM (SCM_EOL):
	      return scm_class_null;
	    default:
	      return scm_class_unknown;
	    }
	}

    case scm_tc3_cons:
      switch (SCM_TYP7 (x))
	{
	case scm_tcs_cons_nimcar:
	  return scm_class_pair;
	case scm_tcs_closures:
	  return scm_class_procedure;
	case scm_tc7_symbol:
	  return scm_class_symbol;
	case scm_tc7_vector:
	case scm_tc7_wvect:
#ifdef HAVE_ARRAYS
	case scm_tc7_bvect:
	case scm_tc7_byvect:
	case scm_tc7_svect:
	case scm_tc7_ivect:
	case scm_tc7_uvect:
	case scm_tc7_fvect:
	case scm_tc7_dvect:
	case scm_tc7_cvect:
#endif
	  return scm_class_vector;
	case scm_tc7_string:
	case scm_tc7_substring:
	  return scm_class_string;
	case scm_tc7_asubr:
	case scm_tc7_subr_0:
	case scm_tc7_subr_1:
	case scm_tc7_cxr:
	case scm_tc7_subr_3:
	case scm_tc7_subr_2:
	case scm_tc7_rpsubr:
	case scm_tc7_subr_1o:
	case scm_tc7_subr_2o:
	case scm_tc7_lsubr_2:
	case scm_tc7_lsubr:
	  if (SCM_SUBR_GENERIC (x) && *SCM_SUBR_GENERIC (x))
	    return scm_class_primitive_generic;
	  else
	    return scm_class_procedure;
	case scm_tc7_cclo:
	  return scm_class_procedure;
	case scm_tc7_pws:
	  return scm_class_procedure_with_setter;

	case scm_tc7_smob:
	  {
	    long type = SCM_TYP16 (x);
	    if (type != scm_tc16_port_with_ps)
	      return scm_smob_class[SCM_TC2SMOBNUM (type)];
	    x = SCM_PORT_WITH_PS_PORT (x);
	    /* fall through to ports */
	  }
	case scm_tc7_port:
	  return scm_port_class[(SCM_WRTNG & SCM_CELL_WORD_0 (x)
				 ? (SCM_RDNG & SCM_CELL_WORD_0 (x)
				    ? SCM_INOUT_PCLASS_INDEX | SCM_PTOBNUM (x)
				    : SCM_OUT_PCLASS_INDEX | SCM_PTOBNUM (x))
				 : SCM_IN_PCLASS_INDEX | SCM_PTOBNUM (x))];
	case scm_tcs_cons_gloc:
	  /* must be a struct */
	  if (SCM_OBJ_CLASS_FLAGS (x) & SCM_CLASSF_GOOPS_VALID)
	    return SCM_CLASS_OF (x);
	  else if (SCM_OBJ_CLASS_FLAGS (x) & SCM_CLASSF_GOOPS)
	    {
	      /* Goops object */
	      if (! SCM_FALSEP (SCM_OBJ_CLASS_REDEF (x)))
		scm_change_object_class (x,
					 SCM_CLASS_OF (x),         /* old */
					 SCM_OBJ_CLASS_REDEF (x)); /* new */
	      return SCM_CLASS_OF (x);
	    }
	  else
	    {
	      /* ordinary struct */
	      SCM handle = scm_struct_create_handle (SCM_STRUCT_VTABLE (x));
	      if (SCM_NFALSEP (SCM_STRUCT_TABLE_CLASS (SCM_CDR (handle))))
		return SCM_STRUCT_TABLE_CLASS (SCM_CDR (handle));
	      else
		{
		  SCM name = SCM_STRUCT_TABLE_NAME (SCM_CDR (handle));
		  SCM class = scm_make_extended_class (SCM_NFALSEP (name)
						       ? SCM_SYMBOL_CHARS (name)
						       : 0);
		  SCM_SET_STRUCT_TABLE_CLASS (SCM_CDR (handle), class);
		  return class;
		}
	    }
	default:
	  if (SCM_CONSP (x))
	    return scm_class_pair;
	  else
	    return scm_class_unknown;
	}

    case scm_tc3_cons_gloc:
    case scm_tc3_tc7_1:
    case scm_tc3_tc7_2:
    case scm_tc3_closure:
      /* Never reached */
      break;
    }
  return scm_class_unknown;
}
#undef FUNC_NAME

/* (SCM_IM_DISPATCH ARGS N-SPECIALIZED
 *   #((TYPE1 ... ENV FORMALS FORM ...) ...)
 *   GF)
 *
 * (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)
{
  int i, n, end, mask;
  SCM ls, methods, z = SCM_CDDR (cache);
  n = SCM_INUM (SCM_CAR (z)); /* maximum number of specializers */
  methods = SCM_CADR (z);

  if (SCM_NIMP (methods))
    {
      /* Prepare for linear search */
      mask = -1;
      i = 0;
      end = SCM_VECTOR_LENGTH (methods);
    }
  else
    {
      /* Compute a hash value */
      int hashset = SCM_INUM (methods);
      int j = n;
      mask = SCM_INUM (SCM_CAR (z = SCM_CDDR (z)));
      methods = SCM_CADR (z);
      i = 0;
      ls = args;
      if (SCM_NIMP (ls))
	do
	  {
	    i += SCM_STRUCT_DATA (scm_class_of (SCM_CAR (ls)))
		 [scm_si_hashsets + hashset];
	    ls = SCM_CDR (ls);
	  }
	while (j-- && SCM_NIMP (ls));
      i &= mask;
      end = i;
    }

  /* Search for match  */
  do
    {
      int j = n;
      z = SCM_VELTS (methods)[i];
      ls = args; /* list of arguments */
      if (SCM_NIMP (ls))
	do
	  {
	    /* More arguments than specifiers => CLASS != ENV */
	    if (! SCM_EQ_P (scm_class_of (SCM_CAR (ls)), SCM_CAR (z)))
	      goto next_method;
	    ls = SCM_CDR (ls);
	    z = SCM_CDR (z);
	  }
	while (j-- && SCM_NIMP (ls));
      /* Fewer arguments than specifiers => CAR != ENV */
      if (!(SCM_IMP (SCM_CAR (z)) || SCM_CONSP (SCM_CAR (z))))
	goto next_method;
      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_IMP (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_LIST1 (a1));
}

SCM
scm_call_generic_2 (SCM gf, SCM a1, SCM a2)
{
  return scm_apply_generic (gf, SCM_LIST2 (a1, a2));
}

SCM
scm_call_generic_3 (SCM gf, SCM a1, SCM a2, SCM a3)
{
  return scm_apply_generic (gf, SCM_LIST3 (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_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_BOOL(SCM_STRUCTP (obj)
                  && SCM_I_OPERATORP (obj)
                  && !SCM_I_ENTITYP (obj));
}
#undef FUNC_NAME

SCM_DEFINE (scm_set_object_procedure_x, "set-object-procedure!", 2, 0, 0, 
            (SCM obj, SCM proc),
	    "Return 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_VALIDATE_PROC (2,proc);
  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_LIST4 (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_EQ_P (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]);
  /* Convert symbol->string */
  pl = scm_makfromstr (SCM_SYMBOL_CHARS (pl), SCM_SYMBOL_LENGTH (pl), 0);
  return scm_i_make_class_object (SCM_STRUCT_VTABLE (class),
				  scm_string_append (SCM_LIST2 (pl, layout)),
				  SCM_CLASS_FLAGS (class));
}
#undef FUNC_NAME

void
scm_init_objects ()
{
  SCM ms = scm_makfrom0str (SCM_METACLASS_STANDARD_LAYOUT);
  SCM mt = scm_make_vtable_vtable (ms, SCM_INUM0,
				   SCM_LIST3 (SCM_BOOL_F, SCM_EOL, SCM_EOL));
  
  SCM os = scm_makfrom0str (SCM_METACLASS_OPERATOR_LAYOUT);
  SCM ot = scm_make_vtable_vtable (os, SCM_INUM0,
				   SCM_LIST3 (SCM_BOOL_F, SCM_EOL, SCM_EOL));
  
  SCM es = scm_makfrom0str (SCM_ENTITY_LAYOUT);
  SCM el = scm_make_struct_layout (es);
  SCM et = scm_make_struct (mt, SCM_INUM0,
			    SCM_LIST4 (el, SCM_BOOL_F, SCM_EOL, SCM_EOL));

  scm_sysintern ("<class>", mt);
  scm_metaclass_standard = mt;
  scm_sysintern ("<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_sysintern ("<entity>", et);

#ifndef SCM_MAGIC_SNARFER
#include "libguile/objects.x"
#endif
}

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/
Commit	Line	Data
950cc72b	1	/* Copyright (C) 1995, 1996, 1999, 2000 Free Software Foundation, Inc.
1d9ee7c7 MD	2	*
	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)
	6	* any later version.
	7	*
	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.
	12	*
	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
	17	*
	18	* As a special exception, the Free Software Foundation gives permission
	19	* for additional uses of the text contained in its release of GUILE.
	20	*
	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.
	26	*
	27	* This exception does not however invalidate any other reasons why
	28	* the executable file might be covered by the GNU General Public License.
	29	*
	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.
	37	*
	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. */
1bbd0b84 GB	41
	42	/* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
	43	gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
	44
1d9ee7c7 MD	45	\f
1d9ee7c7 MD	46
da7f71d7 MD	47	/* This file and objects.h contains those minimal pieces of the Guile
	48	* Object Oriented Programming System which need to be included in
	49	* libguile. See the comments in objects.h.
1d9ee7c7 MD	50	*/
1d9ee7c7 MD	51
a0599745 MD	52	#include "libguile/_scm.h"
	53
	54	#include "libguile/struct.h"
	55	#include "libguile/procprop.h"
	56	#include "libguile/chars.h"
	57	#include "libguile/keywords.h"
	58	#include "libguile/smob.h"
	59	#include "libguile/eval.h"
	60	#include "libguile/alist.h"
	61	#include "libguile/ports.h"
	62	#include "libguile/strings.h"
	63	#include "libguile/vectors.h"
	64
	65	#include "libguile/validate.h"
	66	#include "libguile/objects.h"
1d9ee7c7 MD	67	\f
	68
	69	SCM scm_metaclass_standard;
da7f71d7	70	SCM scm_metaclass_operator;
1d9ee7c7	71
ab7288bc MD	72	/* These variables are filled in by the object system when loaded. */
	73	SCM scm_class_boolean, scm_class_char, scm_class_pair;
	74	SCM scm_class_procedure, scm_class_string, scm_class_symbol;
9de33deb	75	SCM scm_class_procedure_with_setter, scm_class_primitive_generic;
ab7288bc	76	SCM scm_class_vector, scm_class_null;
ed6e0c83 MD	77	SCM scm_class_integer, scm_class_real, scm_class_complex;
ed6e0c83 MD	78	SCM scm_class_unknown;
ab7288bc	79
d0efbe61	80	SCM *scm_port_class = 0;
ed6e0c83 MD	81	SCM *scm_smob_class = 0;
ed6e0c83 MD	82
9de33deb MD	83	SCM scm_no_applicable_method;
9de33deb MD	84
ab7288bc	85	/* This function is used for efficient type dispatch. */
398d8ee1 KN	86	SCM_DEFINE (scm_class_of, "class-of", 1, 0, 0,
398d8ee1 KN	87	(SCM x),
99ca0a7f	88	"Return the class of @var{x}.")
398d8ee1	89	#define FUNC_NAME s_scm_class_of
ab7288bc MD	90	{
	91	switch (SCM_ITAG3 (x))
	92	{
	93	case scm_tc3_int_1:
	94	case scm_tc3_int_2:
	95	return scm_class_integer;
	96
	97	case scm_tc3_imm24:
7866a09b	98	if (SCM_CHARP (x))
ab7288bc MD	99	return scm_class_char;
	100	else
	101	{
	102	switch (SCM_ISYMNUM (x))
	103	{
	104	case SCM_ISYMNUM (SCM_BOOL_F):
	105	case SCM_ISYMNUM (SCM_BOOL_T):
	106	return scm_class_boolean;
	107	case SCM_ISYMNUM (SCM_EOL):
	108	return scm_class_null;
	109	default:
	110	return scm_class_unknown;
	111	}
	112	}
	113
	114	case scm_tc3_cons:
	115	switch (SCM_TYP7 (x))
	116	{
	117	case scm_tcs_cons_nimcar:
	118	return scm_class_pair;
	119	case scm_tcs_closures:
	120	return scm_class_procedure;
28b06554	121	case scm_tc7_symbol:
ab7288bc MD	122	return scm_class_symbol;
	123	case scm_tc7_vector:
	124	case scm_tc7_wvect:
afe5177e	125	#ifdef HAVE_ARRAYS
ab7288bc MD	126	case scm_tc7_bvect:
	127	case scm_tc7_byvect:
	128	case scm_tc7_svect:
	129	case scm_tc7_ivect:
	130	case scm_tc7_uvect:
	131	case scm_tc7_fvect:
	132	case scm_tc7_dvect:
	133	case scm_tc7_cvect:
afe5177e	134	#endif
ab7288bc MD	135	return scm_class_vector;
	136	case scm_tc7_string:
	137	case scm_tc7_substring:
	138	return scm_class_string;
	139	case scm_tc7_asubr:
	140	case scm_tc7_subr_0:
	141	case scm_tc7_subr_1:
	142	case scm_tc7_cxr:
	143	case scm_tc7_subr_3:
	144	case scm_tc7_subr_2:
	145	case scm_tc7_rpsubr:
	146	case scm_tc7_subr_1o:
	147	case scm_tc7_subr_2o:
	148	case scm_tc7_lsubr_2:
	149	case scm_tc7_lsubr:
9de33deb MD	150	if (SCM_SUBR_GENERIC (x) && *SCM_SUBR_GENERIC (x))
	151	return scm_class_primitive_generic;
	152	else
	153	return scm_class_procedure;
ed6e0c83	154	case scm_tc7_cclo:
ab7288bc MD	155	return scm_class_procedure;
	156	case scm_tc7_pws:
	157	return scm_class_procedure_with_setter;
	158
ab7288bc MD	159	case scm_tc7_smob:
ab7288bc MD	160	{
c209c88e	161	long type = SCM_TYP16 (x);
950cc72b	162	if (type != scm_tc16_port_with_ps)
ed6e0c83	163	return scm_smob_class[SCM_TC2SMOBNUM (type)];
55d54750 MD	164	x = SCM_PORT_WITH_PS_PORT (x);
55d54750 MD	165	/* fall through to ports */
ab7288bc	166	}
55d54750	167	case scm_tc7_port:
206d3de3 DH	168	return scm_port_class[(SCM_WRTNG & SCM_CELL_WORD_0 (x)
206d3de3 DH	169	? (SCM_RDNG & SCM_CELL_WORD_0 (x)
55d54750 MD	170	? SCM_INOUT_PCLASS_INDEX \| SCM_PTOBNUM (x)
	171	: SCM_OUT_PCLASS_INDEX \| SCM_PTOBNUM (x))
	172	: SCM_IN_PCLASS_INDEX \| SCM_PTOBNUM (x))];
ab7288bc MD	173	case scm_tcs_cons_gloc:
ab7288bc MD	174	/* must be a struct */
7151229d MD	175	if (SCM_OBJ_CLASS_FLAGS (x) & SCM_CLASSF_GOOPS_VALID)
	176	return SCM_CLASS_OF (x);
	177	else if (SCM_OBJ_CLASS_FLAGS (x) & SCM_CLASSF_GOOPS)
ed6e0c83 MD	178	{
ed6e0c83 MD	179	/* Goops object */
54778cd3	180	if (! SCM_FALSEP (SCM_OBJ_CLASS_REDEF (x)))
ed6e0c83 MD	181	scm_change_object_class (x,
	182	SCM_CLASS_OF (x), /* old */
	183	SCM_OBJ_CLASS_REDEF (x)); /* new */
	184	return SCM_CLASS_OF (x);
	185	}
	186	else
	187	{
	188	/* ordinary struct */
	189	SCM handle = scm_struct_create_handle (SCM_STRUCT_VTABLE (x));
	190	if (SCM_NFALSEP (SCM_STRUCT_TABLE_CLASS (SCM_CDR (handle))))
	191	return SCM_STRUCT_TABLE_CLASS (SCM_CDR (handle));
	192	else
	193	{
	194	SCM name = SCM_STRUCT_TABLE_NAME (SCM_CDR (handle));
	195	SCM class = scm_make_extended_class (SCM_NFALSEP (name)
b24b5e13	196	? SCM_SYMBOL_CHARS (name)
ed6e0c83	197	: 0);
11f2a643	198	SCM_SET_STRUCT_TABLE_CLASS (SCM_CDR (handle), class);
ed6e0c83 MD	199	return class;
	200	}
	201	}
ab7288bc MD	202	default:
	203	if (SCM_CONSP (x))
	204	return scm_class_pair;
	205	else
	206	return scm_class_unknown;
	207	}
	208
	209	case scm_tc3_cons_gloc:
	210	case scm_tc3_tc7_1:
	211	case scm_tc3_tc7_2:
	212	case scm_tc3_closure:
	213	/* Never reached */
	214	break;
	215	}
	216	return scm_class_unknown;
	217	}
398d8ee1	218	#undef FUNC_NAME
ab7288bc	219
a12be546 MD	220	/* (SCM_IM_DISPATCH ARGS N-SPECIALIZED
	221	* #((TYPE1 ... ENV FORMALS FORM ...) ...)
	222	* GF)
	223	*
	224	* (SCM_IM_HASH_DISPATCH ARGS N-SPECIALIZED HASHSET MASK
	225	* #((TYPE1 ... ENV FORMALS FORM ...) ...)
	226	* GF)
	227	*
	228	* ARGS is either a list of expressions, in which case they
	229	* are interpreted as the arguments of an application, or
	230	* a non-pair, which is interpreted as a single expression
	231	* yielding all arguments.
	232	*
	233	* SCM_IM_DISPATCH expressions in generic functions always
	234	* have ARGS = the symbol `args' or the iloc #@0-0.
	235	*
	236	* Need FORMALS in order to support varying arity. This
	237	* also avoids the need for renaming of bindings.
	238	*
	239	* We should probably not complicate this mechanism by
	240	* introducing "optimizations" for getters and setters or
	241	* primitive methods. Getters and setter will normally be
	242	* compiled into @slot-[ref\|set!] or a procedure call.
	243	* They rely on the dispatch performed before executing
	244	* the code which contains them.
	245	*
	246	* We might want to use a more efficient representation of
	247	* this form in the future, perhaps after we have introduced
	248	* low-level support for syntax-case macros.
	249	*/
	250
9de33deb MD	251	SCM
	252	scm_mcache_lookup_cmethod (SCM cache, SCM args)
	253	{
	254	int i, n, end, mask;
	255	SCM ls, methods, z = SCM_CDDR (cache);
	256	n = SCM_INUM (SCM_CAR (z)); /* maximum number of specializers */
	257	methods = SCM_CADR (z);
	258
	259	if (SCM_NIMP (methods))
	260	{
	261	/* Prepare for linear search */
	262	mask = -1;
	263	i = 0;
bfa974f0	264	end = SCM_VECTOR_LENGTH (methods);
9de33deb MD	265	}
	266	else
	267	{
	268	/* Compute a hash value */
	269	int hashset = SCM_INUM (methods);
	270	int j = n;
	271	mask = SCM_INUM (SCM_CAR (z = SCM_CDDR (z)));
	272	methods = SCM_CADR (z);
	273	i = 0;
	274	ls = args;
a12be546 MD	275	if (SCM_NIMP (ls))
	276	do
	277	{
d8c40b9f DH	278	i += SCM_STRUCT_DATA (scm_class_of (SCM_CAR (ls)))
d8c40b9f DH	279	[scm_si_hashsets + hashset];
a12be546 MD	280	ls = SCM_CDR (ls);
a12be546 MD	281	}
4ea6a431	282	while (j-- && SCM_NIMP (ls));
9de33deb MD	283	i &= mask;
	284	end = i;
	285	}
	286
	287	/* Search for match */
	288	do
	289	{
	290	int j = n;
	291	z = SCM_VELTS (methods)[i];
	292	ls = args; /* list of arguments */
a12be546 MD	293	if (SCM_NIMP (ls))
	294	do
	295	{
	296	/* More arguments than specifiers => CLASS != ENV */
54778cd3	297	if (! SCM_EQ_P (scm_class_of (SCM_CAR (ls)), SCM_CAR (z)))
a12be546 MD	298	goto next_method;
	299	ls = SCM_CDR (ls);
	300	z = SCM_CDR (z);
	301	}
4ea6a431	302	while (j-- && SCM_NIMP (ls));
9de33deb	303	/* Fewer arguments than specifiers => CAR != ENV */
0824bbb3	304	if (!(SCM_IMP (SCM_CAR (z)) \|\| SCM_CONSP (SCM_CAR (z))))
9de33deb MD	305	goto next_method;
	306	return z;
	307	next_method:
	308	i = (i + 1) & mask;
	309	} while (i != end);
	310	return SCM_BOOL_F;
	311	}
	312
	313	SCM
a12be546	314	scm_mcache_compute_cmethod (SCM cache, SCM args)
9de33deb MD	315	{
	316	SCM cmethod = scm_mcache_lookup_cmethod (cache, args);
	317	if (SCM_IMP (cmethod))
	318	/* No match - memoize */
	319	return scm_memoize_method (cache, args);
	320	return cmethod;
	321	}
	322
	323	SCM
a12be546	324	scm_apply_generic (SCM gf, SCM args)
9de33deb	325	{
a12be546	326	SCM cmethod = scm_mcache_compute_cmethod (SCM_ENTITY_PROCEDURE (gf), args);
9de33deb MD	327	return scm_eval_body (SCM_CDR (SCM_CMETHOD_CODE (cmethod)),
	328	SCM_EXTEND_ENV (SCM_CAR (SCM_CMETHOD_CODE (cmethod)),
	329	args,
	330	SCM_CMETHOD_ENV (cmethod)));
	331	}
	332
	333	SCM
a12be546	334	scm_call_generic_0 (SCM gf)
9de33deb	335	{
a12be546	336	return scm_apply_generic (gf, SCM_EOL);
9de33deb MD	337	}
	338
	339	SCM
a12be546	340	scm_call_generic_1 (SCM gf, SCM a1)
9de33deb	341	{
a12be546	342	return scm_apply_generic (gf, SCM_LIST1 (a1));
9de33deb MD	343	}
	344
	345	SCM
a12be546 MD	346	scm_call_generic_2 (SCM gf, SCM a1, SCM a2)
	347	{
	348	return scm_apply_generic (gf, SCM_LIST2 (a1, a2));
	349	}
	350
	351	SCM
	352	scm_call_generic_3 (SCM gf, SCM a1, SCM a2, SCM a3)
9de33deb	353	{
a12be546	354	return scm_apply_generic (gf, SCM_LIST3 (a1, a2, a3));
9de33deb MD	355	}
9de33deb MD	356
a1ec6916	357	SCM_DEFINE (scm_entity_p, "entity?", 1, 0, 0,
1bbd0b84	358	(SCM obj),
99ca0a7f	359	"Return @code{#t} if @var{obj} is an entity.")
1bbd0b84	360	#define FUNC_NAME s_scm_entity_p
19c0dec2	361	{
0c95b57d	362	return SCM_BOOL(SCM_STRUCTP (obj) && SCM_I_ENTITYP (obj));
19c0dec2	363	}
1bbd0b84	364	#undef FUNC_NAME
19c0dec2	365
a1ec6916	366	SCM_DEFINE (scm_operator_p, "operator?", 1, 0, 0,
1bbd0b84	367	(SCM obj),
99ca0a7f	368	"Return @code{#t} if @var{obj} is an operator.")
1bbd0b84	369	#define FUNC_NAME s_scm_operator_p
a43a8375	370	{
0b5f3f34	371	return SCM_BOOL(SCM_STRUCTP (obj)
1bbd0b84 GB	372	&& SCM_I_OPERATORP (obj)
1bbd0b84 GB	373	&& !SCM_I_ENTITYP (obj));
a43a8375	374	}
1bbd0b84	375	#undef FUNC_NAME
a43a8375	376
a1ec6916	377	SCM_DEFINE (scm_set_object_procedure_x, "set-object-procedure!", 2, 0, 0,
1bbd0b84	378	(SCM obj, SCM proc),
99ca0a7f MG	379	"Return the object procedure of @var{obj} to @var{proc}.\n"
99ca0a7f MG	380	"@var{obj} must be either an entity or an operator.")
1bbd0b84	381	#define FUNC_NAME s_scm_set_object_procedure_x
47b21050	382	{
0c95b57d	383	SCM_ASSERT (SCM_STRUCTP (obj)
c1a6fd8f MD	384	&& ((SCM_CLASS_FLAGS (obj) & SCM_CLASSF_OPERATOR)
	385	\|\| (SCM_I_ENTITYP (obj)
	386	&& !(SCM_OBJ_CLASS_FLAGS (obj)
	387	& SCM_CLASSF_PURE_GENERIC))),
47b21050 MD	388	obj,
47b21050 MD	389	SCM_ARG1,
1bbd0b84	390	FUNC_NAME);
3b3b36dd	391	SCM_VALIDATE_PROC (2,proc);
a12be546	392	if (SCM_I_ENTITYP (obj))
d8c40b9f	393	SCM_SET_ENTITY_PROCEDURE (obj, proc);
a12be546 MD	394	else
a12be546 MD	395	SCM_OPERATOR_CLASS (obj)->procedure = proc;
47b21050 MD	396	return SCM_UNSPECIFIED;
47b21050 MD	397	}
1bbd0b84	398	#undef FUNC_NAME
47b21050	399
a43a8375	400	#ifdef GUILE_DEBUG
a1ec6916	401	SCM_DEFINE (scm_object_procedure, "object-procedure", 1, 0, 0,
1bbd0b84	402	(SCM obj),
99ca0a7f MG	403	"Return the object procedure of @var{obj}. @var{obj} must be\n"
99ca0a7f MG	404	"an entity or an operator.")
1bbd0b84	405	#define FUNC_NAME s_scm_object_procedure
a43a8375	406	{
0c95b57d	407	SCM_ASSERT (SCM_STRUCTP (obj)
a12be546 MD	408	&& ((SCM_CLASS_FLAGS (obj) & SCM_CLASSF_OPERATOR)
a12be546 MD	409	\|\| SCM_I_ENTITYP (obj)),
1bbd0b84	410	obj, SCM_ARG1, FUNC_NAME);
a43a8375	411	return (SCM_I_ENTITYP (obj)
a12be546 MD	412	? SCM_ENTITY_PROCEDURE (obj)
a12be546 MD	413	: SCM_OPERATOR_CLASS (obj)->procedure);
a43a8375	414	}
1bbd0b84	415	#undef FUNC_NAME
a43a8375 MD	416	#endif /* GUILE_DEBUG */
a43a8375 MD	417
ed6e0c83 MD	418	/* The following procedures are not a part of Goops but a minimal
	419	* object system built upon structs. They are here for those who
	420	* want to implement their own object system.
	421	*/
	422
036737fc MD	423	SCM
	424	scm_i_make_class_object (SCM meta,
	425	SCM layout_string,
	426	unsigned long flags)
47b21050 MD	427	{
47b21050 MD	428	SCM c;
036737fc	429	SCM layout = scm_make_struct_layout (layout_string);
47b21050 MD	430	c = scm_make_struct (meta,
	431	SCM_INUM0,
	432	SCM_LIST4 (layout, SCM_BOOL_F, SCM_EOL, SCM_EOL));
	433	SCM_SET_CLASS_FLAGS (c, flags);
	434	return c;
	435	}
	436
a1ec6916	437	SCM_DEFINE (scm_make_class_object, "make-class-object", 2, 0, 0,
1bbd0b84	438	(SCM metaclass, SCM layout),
99ca0a7f MG	439	"Create a new class object of class @var{metaclass}, with the\n"
99ca0a7f MG	440	"slot layout specified by @var{layout}.")
1bbd0b84	441	#define FUNC_NAME s_scm_make_class_object
47b21050 MD	442	{
47b21050 MD	443	unsigned long flags = 0;
3b3b36dd GB	444	SCM_VALIDATE_STRUCT (1,metaclass);
3b3b36dd GB	445	SCM_VALIDATE_STRING (2,layout);
54778cd3	446	if (SCM_EQ_P (metaclass, scm_metaclass_operator))
47b21050	447	flags = SCM_CLASSF_OPERATOR;
036737fc	448	return scm_i_make_class_object (metaclass, layout, flags);
47b21050	449	}
1bbd0b84	450	#undef FUNC_NAME
47b21050	451
a1ec6916	452	SCM_DEFINE (scm_make_subclass_object, "make-subclass-object", 2, 0, 0,
1bbd0b84	453	(SCM class, SCM layout),
99ca0a7f MG	454	"Create a subclass object of @var{class}, with the slot layout\n"
99ca0a7f MG	455	"specified by @var{layout}.")
1bbd0b84	456	#define FUNC_NAME s_scm_make_subclass_object
47b21050 MD	457	{
47b21050 MD	458	SCM pl;
3b3b36dd GB	459	SCM_VALIDATE_STRUCT (1,class);
3b3b36dd GB	460	SCM_VALIDATE_STRING (2,layout);
d8c40b9f	461	pl = SCM_PACK (SCM_STRUCT_DATA (class) [scm_vtable_index_layout]);
036737fc	462	/* Convert symbol->string */
bfa974f0	463	pl = scm_makfromstr (SCM_SYMBOL_CHARS (pl), SCM_SYMBOL_LENGTH (pl), 0);
036737fc MD	464	return scm_i_make_class_object (SCM_STRUCT_VTABLE (class),
	465	scm_string_append (SCM_LIST2 (pl, layout)),
	466	SCM_CLASS_FLAGS (class));
47b21050	467	}
1bbd0b84	468	#undef FUNC_NAME
47b21050	469
1d9ee7c7 MD	470	void
	471	scm_init_objects ()
	472	{
	473	SCM ms = scm_makfrom0str (SCM_METACLASS_STANDARD_LAYOUT);
3ce4544c	474	SCM mt = scm_make_vtable_vtable (ms, SCM_INUM0,
1d9ee7c7 MD	475	SCM_LIST3 (SCM_BOOL_F, SCM_EOL, SCM_EOL));
1d9ee7c7 MD	476
da7f71d7	477	SCM os = scm_makfrom0str (SCM_METACLASS_OPERATOR_LAYOUT);
3ce4544c	478	SCM ot = scm_make_vtable_vtable (os, SCM_INUM0,
da7f71d7 MD	479	SCM_LIST3 (SCM_BOOL_F, SCM_EOL, SCM_EOL));
da7f71d7 MD	480
1d9ee7c7 MD	481	SCM es = scm_makfrom0str (SCM_ENTITY_LAYOUT);
	482	SCM el = scm_make_struct_layout (es);
	483	SCM et = scm_make_struct (mt, SCM_INUM0,
	484	SCM_LIST4 (el, SCM_BOOL_F, SCM_EOL, SCM_EOL));
	485
19c0dec2	486	scm_sysintern ("<class>", mt);
1d9ee7c7	487	scm_metaclass_standard = mt;
af3645c5	488	scm_sysintern ("<operator-class>", ot);
da7f71d7 MD	489	scm_metaclass_operator = ot;
da7f71d7 MD	490	SCM_SET_CLASS_FLAGS (et, SCM_CLASSF_OPERATOR \| SCM_CLASSF_ENTITY);
135e76f8	491	SCM_SET_CLASS_DESTRUCTOR (et, scm_struct_free_entity);
af3645c5	492	scm_sysintern ("<entity>", et);
47b21050	493
8dc9439f	494	#ifndef SCM_MAGIC_SNARFER
a0599745	495	#include "libguile/objects.x"
8dc9439f	496	#endif
1d9ee7c7	497	}
89e00824 ML	498
	499	/*
	500	Local Variables:
	501	c-file-style: "gnu"
	502	End:
	503	*/