The GOOPS "unbound" value is a unique pair
[bpt/guile.git] / libguile / goops.c
dissimilarity index 82%
index ab4d7d7..286f3c7 100644 (file)
-/* Copyright (C) 1998,1999,2000,2001,2002,2003,2004,2008,2009,2010,2011,2012,2013,2014,2015
- * 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 3 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 software is a derivative work of other copyrighted softwares; the
- * copyright notices of these softwares are placed in the file COPYRIGHTS
- *
- * This file is based upon stklos.c from the STk distribution by
- * Erick Gallesio <eg@unice.fr>.
- */
-
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-#include <stdio.h>
-
-#include "libguile/_scm.h"
-#include "libguile/alist.h"
-#include "libguile/async.h"
-#include "libguile/chars.h"
-#include "libguile/debug.h"
-#include "libguile/dynl.h"
-#include "libguile/dynwind.h"
-#include "libguile/eval.h"
-#include "libguile/gsubr.h"
-#include "libguile/hashtab.h"
-#include "libguile/keywords.h"
-#include "libguile/macros.h"
-#include "libguile/modules.h"
-#include "libguile/ports.h"
-#include "libguile/procprop.h"
-#include "libguile/programs.h"
-#include "libguile/random.h"
-#include "libguile/root.h"
-#include "libguile/smob.h"
-#include "libguile/strings.h"
-#include "libguile/strports.h"
-#include "libguile/vectors.h"
-#include "libguile/vm.h"
-
-#include "libguile/validate.h"
-#include "libguile/goops.h"
-
-#define SPEC_OF(x)  SCM_SLOT (x, scm_si_specializers)
-
-/* Port classes */
-#define SCM_IN_PCLASS_INDEX       0
-#define SCM_OUT_PCLASS_INDEX      SCM_I_MAX_PORT_TYPE_COUNT
-#define SCM_INOUT_PCLASS_INDEX    (2 * SCM_I_MAX_PORT_TYPE_COUNT)
-
-/* this file is a mess. in theory, though, we shouldn't have many SCM references
-   -- most of the references should be to vars. */
-
-static SCM var_slot_unbound = SCM_BOOL_F;
-static SCM var_slot_missing = SCM_BOOL_F;
-static SCM var_compute_cpl = SCM_BOOL_F;
-static SCM var_no_applicable_method = SCM_BOOL_F;
-static SCM var_change_class = SCM_BOOL_F;
-
-SCM_SYMBOL (sym_slot_unbound, "slot-unbound");
-SCM_SYMBOL (sym_slot_missing, "slot-missing");
-SCM_SYMBOL (sym_compute_cpl, "compute-cpl");
-SCM_SYMBOL (sym_no_applicable_method, "no-applicable-method");
-SCM_SYMBOL (sym_memoize_method_x, "memoize-method!");
-SCM_SYMBOL (sym_change_class, "change-class");
-
-SCM_VARIABLE (scm_var_make_extended_generic, "make-extended-generic");
-
-
-/* Class redefinition protocol:
-
-   A class is represented by a heap header h1 which points to a
-   malloc:ed memory block m1.
-
-   When a new version of a class is created, a new header h2 and
-   memory block m2 are allocated.  The headers h1 and h2 then switch
-   pointers so that h1 refers to m2 and h2 to m1.  In this way, names
-   bound to h1 will point to the new class at the same time as h2 will
-   be a handle which the GC will use to free m1.
-
-   The `redefined' slot of m1 will be set to point to h1.  An old
-   instance will have its class pointer (the CAR of the heap header)
-   pointing to m1.  The non-immediate `redefined'-slot in m1 indicates
-   the class modification and the new class pointer can be found via
-   h1.
-*/
-
-#define TEST_CHANGE_CLASS(obj, class)                                 \
-       {                                                              \
-         class = SCM_CLASS_OF (obj);                                  \
-          if (scm_is_true (SCM_OBJ_CLASS_REDEF (obj)))                \
-           {                                                          \
-             scm_change_object_class (obj, class, SCM_OBJ_CLASS_REDEF (obj));\
-             class = SCM_CLASS_OF (obj);                              \
-           }                                                          \
-       }
-
-#define NXT_MTHD_METHODS(m)    (SCM_VELTS (m)[1])
-#define NXT_MTHD_ARGS(m)       (SCM_VELTS (m)[2])
-
-#define SCM_GOOPS_UNBOUND SCM_UNBOUND
-#define SCM_GOOPS_UNBOUNDP(x) (scm_is_eq (x, SCM_GOOPS_UNBOUND))
-
-static int goops_loaded_p = 0;
-static scm_t_rstate *goops_rstate;
-
-/* 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_primitive_generic;
-SCM scm_class_vector, scm_class_null;
-SCM scm_class_integer, scm_class_real, scm_class_complex, scm_class_fraction;
-SCM scm_class_unknown;
-SCM scm_class_top, scm_class_object, scm_class_class;
-SCM scm_class_applicable;
-SCM scm_class_applicable_struct, scm_class_applicable_struct_with_setter;
-SCM scm_class_generic, scm_class_generic_with_setter;
-SCM scm_class_accessor;
-SCM scm_class_extended_generic, scm_class_extended_generic_with_setter;
-SCM scm_class_extended_accessor;
-SCM scm_class_method;
-SCM scm_class_accessor_method;
-SCM scm_class_procedure_class;
-SCM scm_class_applicable_struct_class;
-SCM scm_class_number, scm_class_list;
-SCM scm_class_keyword;
-SCM scm_class_port, scm_class_input_output_port;
-SCM scm_class_input_port, scm_class_output_port;
-SCM scm_class_foreign_slot;
-SCM scm_class_self, scm_class_protected;
-SCM scm_class_hidden, scm_class_opaque, scm_class_read_only;
-SCM scm_class_protected_hidden, scm_class_protected_opaque, scm_class_protected_read_only;
-SCM scm_class_scm;
-SCM scm_class_int, scm_class_float, scm_class_double;
-
-static SCM class_foreign;
-static SCM class_hashtable;
-static SCM class_fluid;
-static SCM class_dynamic_state;
-static SCM class_frame;
-static SCM class_vm_cont;
-static SCM class_bytevector;
-static SCM class_uvec;
-static SCM class_array;
-static SCM class_bitvector;
-
-static SCM vtable_class_map = SCM_BOOL_F;
-
-/* Port classes.  Allocate 3 times the maximum number of port types so that
-   input ports, output ports, and in/out ports can be stored at different
-   offsets.  See `SCM_IN_PCLASS_INDEX' et al.  */
-SCM scm_port_class[3 * SCM_I_MAX_PORT_TYPE_COUNT];
-
-/* SMOB classes.  */
-SCM scm_smob_class[SCM_I_MAX_SMOB_TYPE_COUNT];
-
-SCM scm_no_applicable_method;
-
-SCM_SYMBOL (scm_sym_define_public, "define-public");
-
-static SCM scm_make_unbound (void);
-static SCM scm_unbound_p (SCM obj);
-static SCM scm_assert_bound (SCM value, SCM obj);
-static SCM scm_at_assert_bound_ref (SCM obj, SCM index);
-static SCM scm_sys_goops_loaded (void);
-static SCM scm_make_extended_class_from_symbol (SCM type_name_sym, 
-                                               int applicablep);
-
-
-SCM
-scm_i_define_class_for_vtable (SCM vtable)
-{
-  SCM class;
-
-  scm_i_pthread_mutex_lock (&scm_i_misc_mutex);
-  if (scm_is_false (vtable_class_map))
-    vtable_class_map = scm_c_make_weak_table (0, SCM_WEAK_TABLE_KIND_KEY);
-  scm_i_pthread_mutex_unlock (&scm_i_misc_mutex);
-  
-  if (scm_is_false (scm_struct_vtable_p (vtable)))
-    abort ();
-
-  class = scm_weak_table_refq (vtable_class_map, vtable, SCM_BOOL_F);
-
-  if (scm_is_false (class))
-    {
-      if (SCM_UNPACK (scm_class_class))
-        {
-          SCM name = SCM_VTABLE_NAME (vtable);
-          if (!scm_is_symbol (name))
-            name = scm_string_to_symbol (scm_nullstr);
-
-          class = scm_make_extended_class_from_symbol
-            (name, SCM_VTABLE_FLAG_IS_SET (vtable, SCM_VTABLE_FLAG_APPLICABLE));
-        }
-      else
-        /* `create_struct_classes' will fill this in later.  */
-        class = SCM_BOOL_F;
-
-      /* Don't worry about races.  This only happens when creating a
-         vtable, which happens by definition in one thread.  */
-      scm_weak_table_putq_x (vtable_class_map, vtable, class);
-    }
-
-  return class;
-}
-
-/* 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 if (scm_is_bool (x))
-        return scm_class_boolean;
-      else if (scm_is_null (x))
-        return scm_class_null;
-      else
-        return scm_class_unknown;
-
-    case scm_tc3_cons:
-      switch (SCM_TYP7 (x))
-       {
-       case scm_tcs_cons_nimcar:
-         return scm_class_pair;
-       case scm_tc7_symbol:
-         return scm_class_symbol;
-       case scm_tc7_vector:
-       case scm_tc7_wvect:
-         return scm_class_vector;
-       case scm_tc7_pointer:
-         return class_foreign;
-       case scm_tc7_hashtable:
-         return class_hashtable;
-       case scm_tc7_fluid:
-         return class_fluid;
-       case scm_tc7_dynamic_state:
-         return class_dynamic_state;
-        case scm_tc7_frame:
-         return class_frame;
-        case scm_tc7_keyword:
-         return scm_class_keyword;
-        case scm_tc7_vm_cont:
-         return class_vm_cont;
-       case scm_tc7_bytevector:
-          if (SCM_BYTEVECTOR_ELEMENT_TYPE (x) == SCM_ARRAY_ELEMENT_TYPE_VU8)
-            return class_bytevector;
-          else
-            return class_uvec;
-       case scm_tc7_array:
-          return class_array;
-       case scm_tc7_bitvector:
-          return class_bitvector;
-       case scm_tc7_string:
-         return scm_class_string;
-        case scm_tc7_number:
-          switch SCM_TYP16 (x) {
-          case scm_tc16_big:
-            return scm_class_integer;
-          case scm_tc16_real:
-            return scm_class_real;
-          case scm_tc16_complex:
-            return scm_class_complex;
-         case scm_tc16_fraction:
-           return scm_class_fraction;
-          }
-       case scm_tc7_program:
-         if (SCM_PROGRAM_IS_PRIMITIVE_GENERIC (x)
-              && SCM_UNPACK (*SCM_SUBR_GENERIC (x)))
-           return scm_class_primitive_generic;
-         else
-           return scm_class_procedure;
-
-       case scm_tc7_smob:
-         {
-           scm_t_bits 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_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_is_false (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
-            return scm_i_define_class_for_vtable (SCM_CLASS_OF (x));
-       default:
-         if (scm_is_pair (x))
-           return scm_class_pair;
-         else
-           return scm_class_unknown;
-       }
-
-    case scm_tc3_struct:
-    case scm_tc3_tc7_1:
-    case scm_tc3_tc7_2:
-      /* case scm_tc3_unused: */
-      /* Never reached */
-      break;
-    }
-  return scm_class_unknown;
-}
-#undef FUNC_NAME
-
-/******************************************************************************
- *
- * Compute-cpl
- *
- *   This version doesn't fully handle multiple-inheritance. It serves
- *   only for booting classes and will be overloaded in Scheme
- *
- ******************************************************************************/
-
-static SCM
-map (SCM (*proc) (SCM), SCM ls)
-{
-  if (scm_is_null (ls))
-    return ls;
-  else
-    {
-      SCM res = scm_cons (proc (SCM_CAR (ls)), SCM_EOL);
-      SCM h = res;
-      ls = SCM_CDR (ls);
-      while (scm_is_pair (ls))
-       {
-         SCM_SETCDR (h, scm_cons (proc (SCM_CAR (ls)), SCM_EOL));
-         h = SCM_CDR (h);
-         ls = SCM_CDR (ls);
-       }
-      return res;
-    }
-}
-
-static SCM
-filter_cpl (SCM ls)
-{
-  SCM res = SCM_EOL;
-  while (scm_is_pair (ls))
-    {
-      SCM el = SCM_CAR (ls);
-      if (scm_is_false (scm_c_memq (el, res)))
-       res = scm_cons (el, res);
-      ls = SCM_CDR (ls);
-    }
-  return res;
-}
-
-static SCM
-compute_cpl (SCM class)
-{
-  if (goops_loaded_p)
-    return scm_call_1 (SCM_VARIABLE_REF (var_compute_cpl), class);
-  else
-    {
-      SCM supers = SCM_SLOT (class, scm_si_direct_supers);
-      SCM ls = scm_append (scm_acons (class, supers,
-                                     map (compute_cpl, supers)));
-      return scm_reverse_x (filter_cpl (ls), SCM_EOL);
-    }
-}
-
-/******************************************************************************
- *
- * compute-slots
- *
- ******************************************************************************/
-
-static SCM
-remove_duplicate_slots (SCM l, SCM res, SCM slots_already_seen)
-{
-  SCM tmp;
-
-  if (!scm_is_pair (l))
-    return res;
-
-  tmp = SCM_CAAR (l);
-  if (!scm_is_symbol (tmp))
-    scm_misc_error ("%compute-slots", "bad slot name ~S", scm_list_1 (tmp));
-
-  if (scm_is_false (scm_c_memq (tmp, slots_already_seen))) {
-    res               = scm_cons (SCM_CAR (l), res);
-    slots_already_seen = scm_cons (tmp, slots_already_seen);
-  }
-
-  return remove_duplicate_slots (SCM_CDR (l), res, slots_already_seen);
-}
-
-static void 
-check_cpl (SCM slots, SCM bslots)
-{
-  for (; scm_is_pair (bslots); bslots = SCM_CDR (bslots))
-    if (scm_is_true (scm_assq (SCM_CAAR (bslots), slots)))
-      scm_misc_error ("init-object", "a predefined <class> inherited "
-                      "field cannot be redefined", SCM_EOL);  
-}
-
-static SCM 
-build_class_class_slots (void);
-
-static SCM
-build_slots_list (SCM dslots, SCM cpl)
-{
-  SCM bslots, class_slots;
-  int classp;
-  SCM res = dslots;
-
-  class_slots = SCM_EOL;  
-  classp = scm_is_true (scm_memq (scm_class_class, cpl));
-  
-  if (classp) 
-    {
-      bslots = build_class_class_slots ();
-      check_cpl (res, bslots);
-    }
-  else
-    bslots = SCM_EOL;
-
-  if (scm_is_pair (cpl))
-    {      
-      for (cpl = SCM_CDR (cpl); scm_is_pair (cpl); cpl = SCM_CDR (cpl))
-        {
-          SCM new_slots = SCM_SLOT (SCM_CAR (cpl),
-                                    scm_si_direct_slots);
-          if (classp)
-            {
-              if (!scm_is_eq (SCM_CAR (cpl), scm_class_class))
-                check_cpl (new_slots, bslots);
-              else
-                {
-                  /* Move class slots to the head of the list. */
-                  class_slots = new_slots;
-                  continue;
-                }
-            }   
-          res = scm_append (scm_list_2 (new_slots, res));
-        }
-    }
-  else
-    scm_misc_error ("%compute-slots", "malformed cpl argument in "
-                    "build_slots_list", SCM_EOL);
-
-  /* make sure to add the <class> slots to the head of the list */
-  if (classp)
-    res = scm_append (scm_list_2 (class_slots, res));
-
-  /* res contains a list of slots. Remove slots which appears more than once */
-  return remove_duplicate_slots (scm_reverse (res), SCM_EOL, SCM_EOL);
-}
-
-static SCM
-maplist (SCM ls)
-{
-  SCM orig = ls;
-  while (!scm_is_null (ls))
-    {
-      if (!scm_is_pair (ls))
-        scm_misc_error ("%compute-slots", "malformed ls argument in "
-                        "maplist", SCM_EOL);
-      if (!scm_is_pair (SCM_CAR (ls)))
-        SCM_SETCAR (ls, scm_cons (SCM_CAR (ls), SCM_EOL));
-      ls = SCM_CDR (ls);
-    }
-  return orig;
-}
-
-
-SCM_DEFINE (scm_sys_compute_slots, "%compute-slots", 1, 0, 0,
-           (SCM class),
-           "Return a list consisting of the names of all slots belonging to\n"
-           "class @var{class}, i. e. the slots of @var{class} and of all of\n"
-           "its superclasses.")
-#define FUNC_NAME s_scm_sys_compute_slots
-{
-  SCM_VALIDATE_CLASS (1, class);
-  return build_slots_list (SCM_SLOT (class, scm_si_direct_slots),
-                          SCM_SLOT (class, scm_si_cpl));
-}
-#undef FUNC_NAME
-
-
-/******************************************************************************
- *
- * compute-getters-n-setters
- *
- *   This version doesn't handle slot options. It serves only for booting
- * classes and will be overloaded in Scheme.
- *
- ******************************************************************************/
-
-SCM_KEYWORD (k_init_value, "init-value");
-SCM_KEYWORD (k_init_thunk, "init-thunk");
-
-static SCM
-compute_getters_n_setters (SCM slots)
-{
-  SCM res = SCM_EOL;
-  SCM *cdrloc = &res;
-  long i   = 0;
-
-  for (  ; !scm_is_null (slots); slots = SCM_CDR (slots))
-    {
-      SCM init = SCM_BOOL_F;
-      SCM options = SCM_CDAR (slots);
-      if (!scm_is_null (options))
-       {
-         init = scm_get_keyword (k_init_value, options, SCM_PACK (0));
-         if (SCM_UNPACK (init))
-            {
-              init = scm_primitive_eval (scm_list_3 (scm_sym_lambda,
-                                                     SCM_EOL,
-                                                     scm_list_2 (scm_sym_quote,
-                                                                 init)));
-            }
-         else
-           init = scm_get_keyword (k_init_thunk, options, SCM_BOOL_F);
-       }
-      *cdrloc = scm_cons (scm_cons (SCM_CAAR (slots),
-                                   scm_cons (init,
-                                             scm_from_int (i++))),
-                         SCM_EOL);
-      cdrloc = SCM_CDRLOC (*cdrloc);
-    }
-  return res;
-}
-
-/******************************************************************************
- *
- * initialize-object
- *
- ******************************************************************************/
-
-/*fixme* Manufacture keywords in advance */
-SCM
-scm_i_get_keyword (SCM key, SCM l, long len, SCM default_value, const char *subr)
-{
-  long i;
-
-  for (i = 0; i != len; i += 2)
-    {
-      SCM obj = SCM_CAR (l);
-
-      if (!scm_is_keyword (obj))
-       scm_misc_error (subr, "bad keyword: ~S", scm_list_1 (obj));
-      else if (scm_is_eq (obj, key))
-       return SCM_CADR (l);
-      else
-       l = SCM_CDDR (l);
-    }
-
-  return default_value;
-}
-
-
-SCM_DEFINE (scm_get_keyword, "get-keyword", 3, 0, 0,
-           (SCM key, SCM l, SCM default_value),
-           "Determine an associated value for the keyword @var{key} from\n"
-           "the list @var{l}.  The list @var{l} has to consist of an even\n"
-           "number of elements, where, starting with the first, every\n"
-           "second element is a keyword, followed by its associated value.\n"
-           "If @var{l} does not hold a value for @var{key}, the value\n"
-           "@var{default_value} is returned.")
-#define FUNC_NAME s_scm_get_keyword
-{
-  long len;
-
-  SCM_ASSERT (scm_is_keyword (key), key, SCM_ARG1, FUNC_NAME);
-  len = scm_ilength (l);
-  if (len < 0 || len % 2 == 1)
-    scm_misc_error (FUNC_NAME, "Bad keyword-value list: ~S", scm_list_1 (l));
-
-  return scm_i_get_keyword (key, l, len, default_value, FUNC_NAME);
-}
-#undef FUNC_NAME
-
-
-SCM_KEYWORD (k_init_keyword, "init-keyword");
-
-static SCM get_slot_value (SCM class, SCM obj, SCM slotdef);
-static SCM set_slot_value (SCM class, SCM obj, SCM slotdef, SCM value);
-
-SCM_DEFINE (scm_sys_initialize_object, "%initialize-object", 2, 0, 0,
-           (SCM obj, SCM initargs),
-           "Initialize the object @var{obj} with the given arguments\n"
-           "@var{initargs}.")
-#define FUNC_NAME s_scm_sys_initialize_object
-{
-  SCM tmp, get_n_set, slots;
-  SCM class       = SCM_CLASS_OF (obj);
-  long n_initargs;
-
-  SCM_VALIDATE_INSTANCE (1, obj);
-  n_initargs = scm_ilength (initargs);
-  SCM_ASSERT ((n_initargs & 1) == 0, initargs, SCM_ARG2, FUNC_NAME);
-
-  get_n_set = SCM_SLOT (class, scm_si_getters_n_setters);
-  slots     = SCM_SLOT (class, scm_si_slots);
-
-  /* See for each slot how it must be initialized */
-  for (;
-       !scm_is_null (slots);
-       get_n_set = SCM_CDR (get_n_set), slots = SCM_CDR (slots))
-    {
-      SCM slot_name  = SCM_CAR (slots);
-      SCM slot_value = SCM_GOOPS_UNBOUND;
-
-      if (!scm_is_null (SCM_CDR (slot_name)))
-       {
-         /* This slot admits (perhaps) to be initialized at creation time */
-         long n = scm_ilength (SCM_CDR (slot_name));
-         if (n & 1) /* odd or -1 */
-           SCM_MISC_ERROR ("class contains bogus slot definition: ~S",
-                           scm_list_1 (slot_name));
-         tmp   = scm_i_get_keyword (k_init_keyword,
-                                    SCM_CDR (slot_name),
-                                    n,
-                                    SCM_PACK (0),
-                                    FUNC_NAME);
-         slot_name = SCM_CAR (slot_name);
-         if (SCM_UNPACK (tmp))
-           {
-             /* an initarg was provided for this slot */
-             if (!scm_is_keyword (tmp))
-               SCM_MISC_ERROR ("initarg must be a keyword. It was ~S",
-                               scm_list_1 (tmp));
-             slot_value = scm_i_get_keyword (tmp,
-                                             initargs,
-                                             n_initargs,
-                                             SCM_GOOPS_UNBOUND,
-                                             FUNC_NAME);
-           }
-       }
-
-      if (!SCM_GOOPS_UNBOUNDP (slot_value))
-       /* set slot to provided value */
-       set_slot_value (class, obj, SCM_CAR (get_n_set), slot_value);
-      else
-       {
-         /* set slot to its :init-form if it exists */
-         tmp = SCM_CADAR (get_n_set);
-         if (scm_is_true (tmp))
-            set_slot_value (class,
-                            obj,
-                            SCM_CAR (get_n_set),
-                            scm_call_0 (tmp));
-       }
-    }
-
-  return obj;
-}
-#undef FUNC_NAME
-
-/* NOTE: The following macros are interdependent with code
- *       in goops.scm:compute-getters-n-setters
- */
-#define SCM_GNS_INSTANCE_ALLOCATED_P(gns)      \
-  (SCM_I_INUMP (SCM_CDDR (gns))                        \
-   || (scm_is_pair (SCM_CDDR (gns))            \
-       && scm_is_pair (SCM_CDDDR (gns))                \
-       && scm_is_pair (SCM_CDDDDR (gns))))
-#define SCM_GNS_INDEX(gns)                     \
-  (SCM_I_INUMP (SCM_CDDR (gns))                        \
-   ? SCM_I_INUM (SCM_CDDR (gns))               \
-   : scm_to_long (SCM_CAR (SCM_CDDDDR (gns))))
-#define SCM_GNS_SIZE(gns)                      \
-  (SCM_I_INUMP (SCM_CDDR (gns))                        \
-   ? 1                                         \
-   : scm_to_long (SCM_CADR (SCM_CDDDDR (gns))))
-
-SCM_KEYWORD (k_class, "class");
-SCM_KEYWORD (k_allocation, "allocation");
-SCM_KEYWORD (k_instance, "instance");
-
-SCM_DEFINE (scm_sys_prep_layout_x, "%prep-layout!", 1, 0, 0,
-           (SCM class),
-           "")
-#define FUNC_NAME s_scm_sys_prep_layout_x
-{
-  SCM slots, getters_n_setters, nfields;
-  unsigned long int n, i;
-  char *s;
-  SCM layout;
-
-  SCM_VALIDATE_INSTANCE (1, class);
-  slots = SCM_SLOT (class, scm_si_slots);
-  getters_n_setters = SCM_SLOT (class, scm_si_getters_n_setters);
-  nfields = SCM_SLOT (class, scm_si_nfields);
-  if (!SCM_I_INUMP (nfields) || SCM_I_INUM (nfields) < 0)
-    SCM_MISC_ERROR ("bad value in nfields slot: ~S",
-                   scm_list_1 (nfields));
-  n = 2 * SCM_I_INUM (nfields);
-  if (n < sizeof (SCM_CLASS_CLASS_LAYOUT) - 1
-      && SCM_SUBCLASSP (class, scm_class_class))
-    SCM_MISC_ERROR ("class object doesn't have enough fields: ~S",
-                   scm_list_1 (nfields));
-
-  layout = scm_i_make_string (n, &s, 0);
-  i = 0;
-  while (scm_is_pair (getters_n_setters))
-    {
-      if (SCM_GNS_INSTANCE_ALLOCATED_P (SCM_CAR (getters_n_setters)))
-       {
-         SCM type;
-         int len, index, size;
-         char p, a;
-
-         if (i >= n || !scm_is_pair (slots))
-           goto inconsistent;
-         
-         /* extract slot type */
-         len = scm_ilength (SCM_CDAR (slots));
-         type = scm_i_get_keyword (k_class, SCM_CDAR (slots),
-                                   len, SCM_BOOL_F, FUNC_NAME);
-         /* determine slot GC protection and access mode */
-         if (scm_is_false (type))
-           {
-             p = 'p';
-             a = 'w';
-           }
-         else
-           {
-             if (!SCM_CLASSP (type))
-               SCM_MISC_ERROR ("bad slot class", SCM_EOL);
-             else if (SCM_SUBCLASSP (type, scm_class_foreign_slot))
-               {
-                 if (SCM_SUBCLASSP (type, scm_class_self))
-                   p = 's';
-                 else if (SCM_SUBCLASSP (type, scm_class_protected))
-                   p = 'p';
-                 else
-                   p = 'u';
-
-                 if (SCM_SUBCLASSP (type, scm_class_opaque))
-                   a = 'o';
-                 else if (SCM_SUBCLASSP (type, scm_class_read_only))
-                   a = 'r';
-                 else if (SCM_SUBCLASSP (type, scm_class_hidden))
-                   a = 'h';
-                 else
-                   a = 'w';
-               }
-             else
-               {
-                 p = 'p';
-                 a = 'w';
-               }
-           }
-      
-         index = SCM_GNS_INDEX (SCM_CAR (getters_n_setters));
-         if (index != (i >> 1))
-           goto inconsistent;
-         size = SCM_GNS_SIZE (SCM_CAR (getters_n_setters));
-         while (size)
-           {
-             s[i++] = p;
-             s[i++] = a;
-             --size;
-           }
-       }
-      slots = SCM_CDR (slots);
-      getters_n_setters = SCM_CDR (getters_n_setters);
-    }
-  if (!scm_is_null (slots))
-    {
-    inconsistent:
-      SCM_MISC_ERROR ("inconsistent getters-n-setters", SCM_EOL);
-    }
-  SCM_SET_VTABLE_LAYOUT (class, scm_string_to_symbol (layout));
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-static void prep_hashsets (SCM);
-
-SCM_DEFINE (scm_sys_inherit_magic_x, "%inherit-magic!", 2, 0, 0,
-           (SCM class, SCM dsupers),
-           "")
-#define FUNC_NAME s_scm_sys_inherit_magic_x
-{
-  SCM_VALIDATE_INSTANCE (1, class);
-  scm_i_struct_inherit_vtable_magic (SCM_CLASS_OF (class), class);
-  SCM_SET_CLASS_FLAGS (class, SCM_CLASSF_GOOPS_OR_VALID);
-
-  prep_hashsets (class);
-
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-static void
-prep_hashsets (SCM class)
-{
-  unsigned int i;
-
-  for (i = 0; i < 8; ++i)
-    SCM_SET_HASHSET (class, i, scm_c_uniform32 (goops_rstate));
-}
-
-/******************************************************************************/
-
-SCM
-scm_basic_basic_make_class (SCM class, SCM name, SCM dsupers, SCM dslots)
-{
-  SCM z, cpl, slots, nfields, g_n_s;
-
-  /* Allocate one instance */
-  z = scm_make_struct (class, SCM_INUM0, SCM_EOL);
-
-  /* Initialize its slots */
-  SCM_SET_SLOT (z, scm_si_direct_supers, dsupers);
-  cpl   = compute_cpl (z);
-  slots = build_slots_list (maplist (dslots), cpl);
-  nfields = scm_from_int (scm_ilength (slots));
-  g_n_s = compute_getters_n_setters (slots);
-
-  SCM_SET_SLOT (z, scm_vtable_index_name, name);
-  SCM_SET_SLOT (z, scm_si_direct_slots, dslots);
-  SCM_SET_SLOT (z, scm_si_direct_subclasses, SCM_EOL);
-  SCM_SET_SLOT (z, scm_si_direct_methods, SCM_EOL);
-  SCM_SET_SLOT (z, scm_si_cpl, cpl);
-  SCM_SET_SLOT (z, scm_si_slots, slots);
-  SCM_SET_SLOT (z, scm_si_nfields, nfields);
-  SCM_SET_SLOT (z, scm_si_getters_n_setters, g_n_s);
-  SCM_SET_SLOT (z, scm_si_redefined, SCM_BOOL_F);
-
-  /* Add this class in the direct-subclasses slot of dsupers */
-  {
-    SCM tmp;
-    for (tmp = dsupers; !scm_is_null (tmp); tmp = SCM_CDR (tmp))
-      SCM_SET_SLOT (SCM_CAR (tmp), scm_si_direct_subclasses,
-                   scm_cons (z, SCM_SLOT (SCM_CAR (tmp),
-                                          scm_si_direct_subclasses)));
-  }
-
-  return z;
-}
-
-SCM
-scm_basic_make_class (SCM class, SCM name, SCM dsupers, SCM dslots)
-{
-  SCM z = scm_basic_basic_make_class (class, name, dsupers, dslots);
-  scm_sys_prep_layout_x (z);
-  scm_sys_inherit_magic_x (z, dsupers);
-  return z;
-}
-
-/******************************************************************************/
-
-SCM_SYMBOL (sym_layout, "layout");
-SCM_SYMBOL (sym_flags, "flags");
-SCM_SYMBOL (sym_self, "%self");
-SCM_SYMBOL (sym_instance_finalizer, "instance-finalizer");
-SCM_SYMBOL (sym_reserved_0, "%reserved-0");
-SCM_SYMBOL (sym_reserved_1, "%reserved-1");
-SCM_SYMBOL (sym_print, "print");
-SCM_SYMBOL (sym_procedure, "procedure");
-SCM_SYMBOL (sym_setter, "setter");
-SCM_SYMBOL (sym_redefined, "redefined");
-SCM_SYMBOL (sym_h0, "h0");
-SCM_SYMBOL (sym_h1, "h1");
-SCM_SYMBOL (sym_h2, "h2");
-SCM_SYMBOL (sym_h3, "h3");
-SCM_SYMBOL (sym_h4, "h4");
-SCM_SYMBOL (sym_h5, "h5");
-SCM_SYMBOL (sym_h6, "h6");
-SCM_SYMBOL (sym_h7, "h7");
-SCM_SYMBOL (sym_name, "name");
-SCM_SYMBOL (sym_direct_supers, "direct-supers");
-SCM_SYMBOL (sym_direct_slots, "direct-slots");
-SCM_SYMBOL (sym_direct_subclasses, "direct-subclasses");
-SCM_SYMBOL (sym_direct_methods, "direct-methods");
-SCM_SYMBOL (sym_cpl, "cpl");
-SCM_SYMBOL (sym_default_slot_definition_class, "default-slot-definition-class");
-SCM_SYMBOL (sym_slots, "slots");
-SCM_SYMBOL (sym_getters_n_setters, "getters-n-setters");
-SCM_SYMBOL (sym_nfields, "nfields");
-
-
-static SCM
-build_class_class_slots (void)
-{
-  /* has to be kept in sync with SCM_VTABLE_BASE_LAYOUT and
-     SCM_CLASS_CLASS_LAYOUT */
-  return scm_list_n (
-    scm_list_3 (sym_layout, k_class, scm_class_protected_read_only),
-    scm_list_3 (sym_flags, k_class, scm_class_hidden),
-    scm_list_3 (sym_self, k_class, scm_class_self),
-    scm_list_3 (sym_instance_finalizer, k_class, scm_class_hidden),
-    scm_list_1 (sym_print),
-    scm_list_3 (sym_name, k_class, scm_class_protected_hidden),
-    scm_list_3 (sym_reserved_0, k_class, scm_class_hidden),
-    scm_list_3 (sym_reserved_1, k_class, scm_class_hidden),
-    scm_list_1 (sym_redefined),
-    scm_list_3 (sym_h0, k_class, scm_class_int),
-    scm_list_3 (sym_h1, k_class, scm_class_int),
-    scm_list_3 (sym_h2, k_class, scm_class_int),
-    scm_list_3 (sym_h3, k_class, scm_class_int),
-    scm_list_3 (sym_h4, k_class, scm_class_int),
-    scm_list_3 (sym_h5, k_class, scm_class_int),
-    scm_list_3 (sym_h6, k_class, scm_class_int),
-    scm_list_3 (sym_h7, k_class, scm_class_int),
-    scm_list_1 (sym_direct_supers),
-    scm_list_1 (sym_direct_slots),
-    scm_list_1 (sym_direct_subclasses),
-    scm_list_1 (sym_direct_methods),
-    scm_list_1 (sym_cpl),
-    scm_list_1 (sym_default_slot_definition_class),
-    scm_list_1 (sym_slots),
-    scm_list_1 (sym_getters_n_setters),
-    scm_list_1 (sym_nfields),
-    SCM_UNDEFINED);
-}
-
-static void
-create_basic_classes (void)
-{
-  /* SCM slots_of_class = build_class_class_slots (); */
-
-  /**** <class> ****/
-  SCM cs = scm_from_locale_string (SCM_CLASS_CLASS_LAYOUT);
-  SCM name = scm_from_latin1_symbol ("<class>");
-  scm_class_class = scm_i_make_vtable_vtable (cs);
-  SCM_SET_CLASS_FLAGS (scm_class_class, (SCM_CLASSF_GOOPS_OR_VALID
-                                        | SCM_CLASSF_METACLASS));
-
-  SCM_SET_SLOT (scm_class_class, scm_vtable_index_name, name);
-  SCM_SET_SLOT (scm_class_class, scm_si_direct_supers, SCM_EOL);  /* will be changed */
-  /* SCM_SET_SLOT (scm_class_class, scm_si_direct_slots, slots_of_class); */
-  SCM_SET_SLOT (scm_class_class, scm_si_direct_subclasses, SCM_EOL);
-  SCM_SET_SLOT (scm_class_class, scm_si_direct_methods, SCM_EOL);
-  SCM_SET_SLOT (scm_class_class, scm_si_cpl, SCM_EOL);  /* will be changed */
-  /* SCM_SET_SLOT (scm_class_class, scm_si_slots, slots_of_class); */
-  SCM_SET_SLOT (scm_class_class, scm_si_nfields, scm_from_int (SCM_N_CLASS_SLOTS));
-  /* SCM_SET_SLOT (scm_class_class, scm_si_getters_n_setters,
-                   compute_getters_n_setters (slots_of_class)); */
-  SCM_SET_SLOT (scm_class_class, scm_si_redefined, SCM_BOOL_F);
-
-  prep_hashsets (scm_class_class);
-
-  scm_module_define (scm_module_goops, name, scm_class_class);
-
-  /**** <top> ****/
-  name = scm_from_latin1_symbol ("<top>");
-  scm_class_top = scm_basic_make_class (scm_class_class, name,
-                                        SCM_EOL, SCM_EOL);
-
-  scm_module_define (scm_module_goops, name, scm_class_top);
-
-  /**** <object> ****/
-  name  = scm_from_latin1_symbol ("<object>");
-  scm_class_object = scm_basic_make_class (scm_class_class, name,
-                                           scm_list_1 (scm_class_top), SCM_EOL);
-
-  scm_module_define (scm_module_goops, name, scm_class_object);
-
-  /* <top> <object> and <class> were partially initialized. Correct them here */
-  SCM_SET_SLOT (scm_class_object, scm_si_direct_subclasses, scm_list_1 (scm_class_class));
-
-  SCM_SET_SLOT (scm_class_class, scm_si_direct_supers, scm_list_1 (scm_class_object));
-  SCM_SET_SLOT (scm_class_class, scm_si_cpl, scm_list_3 (scm_class_class, scm_class_object, scm_class_top));
-}
-
-/******************************************************************************/
-
-SCM_DEFINE (scm_instance_p, "instance?", 1, 0, 0,
-           (SCM obj),
-           "Return @code{#t} if @var{obj} is an instance.")
-#define FUNC_NAME s_scm_instance_p
-{
-  return scm_from_bool (SCM_INSTANCEP (obj));
-}
-#undef FUNC_NAME
-
-
-/******************************************************************************
- *
- * Meta object accessors
- *
- ******************************************************************************/
-SCM_DEFINE (scm_class_name, "class-name",  1, 0, 0,
-           (SCM obj),
-           "Return the class name of @var{obj}.")
-#define FUNC_NAME s_scm_class_name
-{
-  SCM_VALIDATE_CLASS (1, obj);
-  return scm_slot_ref (obj, sym_name);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_class_direct_supers, "class-direct-supers", 1, 0, 0,
-           (SCM obj),
-           "Return the direct superclasses of the class @var{obj}.")
-#define FUNC_NAME s_scm_class_direct_supers
-{
-  SCM_VALIDATE_CLASS (1, obj);
-  return scm_slot_ref (obj, sym_direct_supers);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_class_direct_slots, "class-direct-slots", 1, 0, 0,
-           (SCM obj),
-           "Return the direct slots of the class @var{obj}.")
-#define FUNC_NAME s_scm_class_direct_slots
-{
-  SCM_VALIDATE_CLASS (1, obj);
-  return scm_slot_ref (obj, sym_direct_slots);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_class_direct_subclasses, "class-direct-subclasses", 1, 0, 0,
-           (SCM obj),
-           "Return the direct subclasses of the class @var{obj}.")
-#define FUNC_NAME s_scm_class_direct_subclasses
-{
-  SCM_VALIDATE_CLASS (1, obj);
-  return scm_slot_ref(obj, sym_direct_subclasses);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_class_direct_methods, "class-direct-methods", 1, 0, 0,
-           (SCM obj),
-           "Return the direct methods of the class @var{obj}")
-#define FUNC_NAME s_scm_class_direct_methods
-{
-  SCM_VALIDATE_CLASS (1, obj);
-  return scm_slot_ref (obj, sym_direct_methods);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_class_precedence_list, "class-precedence-list", 1, 0, 0,
-           (SCM obj),
-           "Return the class precedence list of the class @var{obj}.")
-#define FUNC_NAME s_scm_class_precedence_list
-{
-  SCM_VALIDATE_CLASS (1, obj);
-  return scm_slot_ref (obj, sym_cpl);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_class_slots, "class-slots", 1, 0, 0,
-           (SCM obj),
-           "Return the slot list of the class @var{obj}.")
-#define FUNC_NAME s_scm_class_slots
-{
-  SCM_VALIDATE_CLASS (1, obj);
-  return scm_slot_ref (obj, sym_slots);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_generic_function_name, "generic-function-name", 1, 0, 0,
-           (SCM obj),
-           "Return the name of the generic function @var{obj}.")
-#define FUNC_NAME s_scm_generic_function_name
-{
-  SCM_VALIDATE_GENERIC (1, obj);
-  return scm_procedure_property (obj, scm_sym_name);
-}
-#undef FUNC_NAME
-
-SCM_SYMBOL (sym_methods, "methods");
-SCM_SYMBOL (sym_extended_by, "extended-by");
-SCM_SYMBOL (sym_extends, "extends");
-
-static
-SCM fold_downward_gf_methods (SCM method_lists, SCM gf)
-{
-  SCM gfs = scm_slot_ref (gf, sym_extended_by);
-  method_lists = scm_cons (scm_slot_ref (gf, sym_methods), method_lists);
-  while (!scm_is_null (gfs))
-    {
-      method_lists = fold_downward_gf_methods (method_lists, SCM_CAR (gfs));
-      gfs = SCM_CDR (gfs);
-    }
-  return method_lists;
-}
-
-static
-SCM fold_upward_gf_methods (SCM method_lists, SCM gf)
-{
-  if (SCM_IS_A_P (gf, scm_class_extended_generic))
-    {
-      SCM gfs = scm_slot_ref (gf, sym_extends);
-      while (!scm_is_null (gfs))
-       {
-         SCM methods = scm_slot_ref (SCM_CAR (gfs), sym_methods);
-         method_lists = fold_upward_gf_methods (scm_cons (methods,
-                                                          method_lists),
-                                                SCM_CAR (gfs));
-         gfs = SCM_CDR (gfs);
-       }
-    }
-  return method_lists;
-}
-
-SCM_DEFINE (scm_generic_function_methods, "generic-function-methods", 1, 0, 0,
-           (SCM obj),
-           "Return the methods of the generic function @var{obj}.")
-#define FUNC_NAME s_scm_generic_function_methods
-{
-  SCM methods;
-  SCM_VALIDATE_GENERIC (1, obj);
-  methods = fold_upward_gf_methods (SCM_EOL, obj);
-  methods = fold_downward_gf_methods (methods, obj);
-  return scm_append (methods);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_method_generic_function, "method-generic-function", 1, 0, 0,
-           (SCM obj),
-           "Return the generic function for the method @var{obj}.")
-#define FUNC_NAME s_scm_method_generic_function
-{
-  SCM_VALIDATE_METHOD (1, obj);
-  return scm_slot_ref (obj, scm_from_latin1_symbol ("generic-function"));
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_method_specializers, "method-specializers", 1, 0, 0,
-           (SCM obj),
-           "Return specializers of the method @var{obj}.")
-#define FUNC_NAME s_scm_method_specializers
-{
-  SCM_VALIDATE_METHOD (1, obj);
-  return scm_slot_ref (obj, scm_from_latin1_symbol ("specializers"));
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_method_procedure, "method-procedure", 1, 0, 0,
-           (SCM obj),
-           "Return the procedure of the method @var{obj}.")
-#define FUNC_NAME s_scm_method_procedure
-{
-  SCM_VALIDATE_METHOD (1, obj);
-  return scm_slot_ref (obj, sym_procedure);
-}
-#undef FUNC_NAME
-
-/******************************************************************************
- *
- * S l o t   a c c e s s
- *
- ******************************************************************************/
-
-SCM_DEFINE (scm_make_unbound, "make-unbound", 0, 0, 0,
-           (),
-           "Return the unbound value.")
-#define FUNC_NAME s_scm_make_unbound
-{
-  return SCM_GOOPS_UNBOUND;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_unbound_p, "unbound?", 1, 0, 0,
-           (SCM obj),
-           "Return @code{#t} if @var{obj} is unbound.")
-#define FUNC_NAME s_scm_unbound_p
-{
-  return SCM_GOOPS_UNBOUNDP (obj) ? SCM_BOOL_T : SCM_BOOL_F;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_assert_bound, "assert-bound", 2, 0, 0,
-           (SCM value, SCM obj),
-           "Return @var{value} if it is bound, and invoke the\n"
-           "@var{slot-unbound} method of @var{obj} if it is not.")
-#define FUNC_NAME s_scm_assert_bound
-{
-  if (SCM_GOOPS_UNBOUNDP (value))
-    return scm_call_1 (SCM_VARIABLE_REF (var_slot_unbound), obj);
-  return value;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_at_assert_bound_ref, "@assert-bound-ref", 2, 0, 0,
-           (SCM obj, SCM index),
-           "Like @code{assert-bound}, but use @var{index} for accessing\n"
-           "the value from @var{obj}.")
-#define FUNC_NAME s_scm_at_assert_bound_ref
-{
-  SCM value = SCM_SLOT (obj, scm_to_int (index));
-  if (SCM_GOOPS_UNBOUNDP (value))
-    return scm_call_1 (SCM_VARIABLE_REF (var_slot_unbound), obj);
-  return value;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_sys_fast_slot_ref, "%fast-slot-ref", 2, 0, 0,
-           (SCM obj, SCM index),
-           "Return the slot value with index @var{index} from @var{obj}.")
-#define FUNC_NAME s_scm_sys_fast_slot_ref
-{
-  scm_t_bits i;
-
-  SCM_VALIDATE_INSTANCE (1, obj);
-  i = scm_to_unsigned_integer (index, 0,
-                              SCM_I_INUM (SCM_SLOT (SCM_CLASS_OF (obj),
-                                                    scm_si_nfields))
-                              - 1);
-  return SCM_SLOT (obj, i);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_sys_fast_slot_set_x, "%fast-slot-set!", 3, 0, 0,
-           (SCM obj, SCM index, SCM value),
-           "Set the slot with index @var{index} in @var{obj} to\n"
-           "@var{value}.")
-#define FUNC_NAME s_scm_sys_fast_slot_set_x
-{
-  scm_t_bits i;
-
-  SCM_VALIDATE_INSTANCE (1, obj);
-  i = scm_to_unsigned_integer (index, 0,
-                              SCM_I_INUM (SCM_SLOT (SCM_CLASS_OF (obj),
-                                                    scm_si_nfields))
-                              - 1);
-
-  SCM_SET_SLOT (obj, i, value);
-
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-
-\f
-/** Utilities **/
-
-/* In the future, this function will return the effective slot
- * definition associated with SLOT_NAME.  Now it just returns some of
- * the information which will be stored in the effective slot
- * definition.
- */
-
-static SCM
-slot_definition_using_name (SCM class, SCM slot_name)
-{
-  register SCM slots = SCM_SLOT (class, scm_si_getters_n_setters);
-  for (; !scm_is_null (slots); slots = SCM_CDR (slots))
-    if (scm_is_eq (SCM_CAAR (slots), slot_name))
-      return SCM_CAR (slots);
-  return SCM_BOOL_F;
-}
-
-static SCM
-get_slot_value (SCM class SCM_UNUSED, SCM obj, SCM slotdef)
-#define FUNC_NAME "%get-slot-value"
-{
-  SCM access = SCM_CDDR (slotdef);
-  /* Two cases here:
-   *   - access is an integer (the offset of this slot in the slots vector)
-   *   - otherwise (car access) is the getter function to apply
-   *
-   * Instances have never more than SCM_MOST_POSITIVE_FIXNUM slots, so
-   * we can just assume fixnums here.
-   */
-  if (SCM_I_INUMP (access))
-    /* Don't poke at the slots directly, because scm_struct_ref handles the
-       access bits for us. */
-    return scm_struct_ref (obj, access);
-  else
-    return scm_call_1 (SCM_CAR (access), obj);
-}
-#undef FUNC_NAME
-
-static SCM
-get_slot_value_using_name (SCM class, SCM obj, SCM slot_name)
-{
-  SCM slotdef = slot_definition_using_name (class, slot_name);
-  if (scm_is_true (slotdef))
-    return get_slot_value (class, obj, slotdef);
-  else
-    return scm_call_3 (SCM_VARIABLE_REF (var_slot_missing), class, obj, slot_name);
-}
-
-static SCM
-set_slot_value (SCM class SCM_UNUSED, SCM obj, SCM slotdef, SCM value)
-#define FUNC_NAME "%set-slot-value"
-{
-  SCM access = SCM_CDDR (slotdef);
-  /* Two cases here:
-   *   - access is an integer (the offset of this slot in the slots vector)
-   *   - otherwise (cadr access) is the setter function to apply
-   *
-   * Instances have never more than SCM_MOST_POSITIVE_FIXNUM slots, so
-   * we can just assume fixnums here.
-   */
-  if (SCM_I_INUMP (access))
-    /* obey permissions bits via going through struct-set! */
-    scm_struct_set_x (obj, access, value);
-  else
-    /* ((cadr l) obj value) */
-    scm_call_2 (SCM_CADR (access), obj, value);
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-static SCM
-set_slot_value_using_name (SCM class, SCM obj, SCM slot_name, SCM value)
-{
-  SCM slotdef = slot_definition_using_name (class, slot_name);
-  if (scm_is_true (slotdef))
-    return set_slot_value (class, obj, slotdef, value);
-  else
-    return scm_call_4 (SCM_VARIABLE_REF (var_slot_missing), class, obj, slot_name, value);
-}
-
-static SCM
-test_slot_existence (SCM class SCM_UNUSED, SCM obj, SCM slot_name)
-{
-  register SCM l;
-
-  for (l = SCM_ACCESSORS_OF (obj); !scm_is_null (l); l = SCM_CDR (l))
-    if (scm_is_eq (SCM_CAAR (l), slot_name))
-      return SCM_BOOL_T;
-
-  return SCM_BOOL_F;
-}
-
-               /* ======================================== */
-
-SCM_DEFINE (scm_slot_ref_using_class, "slot-ref-using-class", 3, 0, 0,
-           (SCM class, SCM obj, SCM slot_name),
-           "")
-#define FUNC_NAME s_scm_slot_ref_using_class
-{
-  SCM res;
-
-  SCM_VALIDATE_CLASS (1, class);
-  SCM_VALIDATE_INSTANCE (2, obj);
-  SCM_VALIDATE_SYMBOL (3, slot_name);
-
-  res = get_slot_value_using_name (class, obj, slot_name);
-  if (SCM_GOOPS_UNBOUNDP (res))
-    return scm_call_3 (SCM_VARIABLE_REF (var_slot_unbound), class, obj, slot_name);
-  return res;
-}
-#undef FUNC_NAME
-
-
-SCM_DEFINE (scm_slot_set_using_class_x, "slot-set-using-class!", 4, 0, 0,
-           (SCM class, SCM obj, SCM slot_name, SCM value),
-           "")
-#define FUNC_NAME s_scm_slot_set_using_class_x
-{
-  SCM_VALIDATE_CLASS (1, class);
-  SCM_VALIDATE_INSTANCE (2, obj);
-  SCM_VALIDATE_SYMBOL (3, slot_name);
-
-  return set_slot_value_using_name (class, obj, slot_name, value);
-}
-#undef FUNC_NAME
-
-
-SCM_DEFINE (scm_slot_bound_using_class_p, "slot-bound-using-class?", 3, 0, 0,
-           (SCM class, SCM obj, SCM slot_name),
-           "")
-#define FUNC_NAME s_scm_slot_bound_using_class_p
-{
-  SCM_VALIDATE_CLASS (1, class);
-  SCM_VALIDATE_INSTANCE (2, obj);
-  SCM_VALIDATE_SYMBOL (3, slot_name);
-
-  return (SCM_GOOPS_UNBOUNDP (get_slot_value_using_name (class, obj, slot_name))
-         ? SCM_BOOL_F
-         : SCM_BOOL_T);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_slot_exists_using_class_p, "slot-exists-using-class?", 3, 0, 0,
-           (SCM class, SCM obj, SCM slot_name),
-           "")
-#define FUNC_NAME s_scm_slot_exists_using_class_p
-{
-  SCM_VALIDATE_CLASS (1, class);
-  SCM_VALIDATE_INSTANCE (2, obj);
-  SCM_VALIDATE_SYMBOL (3, slot_name);
-  return test_slot_existence (class, obj, slot_name);
-}
-#undef FUNC_NAME
-
-
-               /* ======================================== */
-
-SCM_DEFINE (scm_slot_ref, "slot-ref", 2, 0, 0,
-           (SCM obj, SCM slot_name),
-           "Return the value from @var{obj}'s slot with the name\n"
-           "@var{slot_name}.")
-#define FUNC_NAME s_scm_slot_ref
-{
-  SCM res, class;
-
-  SCM_VALIDATE_INSTANCE (1, obj);
-  TEST_CHANGE_CLASS (obj, class);
-
-  res = get_slot_value_using_name (class, obj, slot_name);
-  if (SCM_GOOPS_UNBOUNDP (res))
-    return scm_call_3 (SCM_VARIABLE_REF (var_slot_unbound), class, obj, slot_name);
-  return res;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_slot_set_x, "slot-set!", 3, 0, 0,
-           (SCM obj, SCM slot_name, SCM value),
-           "Set the slot named @var{slot_name} of @var{obj} to @var{value}.")
-#define FUNC_NAME s_scm_slot_set_x
-{
-  SCM class;
-
-  SCM_VALIDATE_INSTANCE (1, obj);
-  TEST_CHANGE_CLASS(obj, class);
-
-  return set_slot_value_using_name (class, obj, slot_name, value);
-}
-#undef FUNC_NAME
-
-const char *scm_s_slot_set_x = s_scm_slot_set_x;
-
-SCM_DEFINE (scm_slot_bound_p, "slot-bound?", 2, 0, 0,
-           (SCM obj, SCM slot_name),
-           "Return @code{#t} if the slot named @var{slot_name} of @var{obj}\n"
-           "is bound.")
-#define FUNC_NAME s_scm_slot_bound_p
-{
-  SCM class;
-
-  SCM_VALIDATE_INSTANCE (1, obj);
-  TEST_CHANGE_CLASS(obj, class);
-
-  return (SCM_GOOPS_UNBOUNDP (get_slot_value_using_name (class,
-                                                        obj,
-                                                        slot_name))
-         ? SCM_BOOL_F
-         : SCM_BOOL_T);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_slot_exists_p, "slot-exists?", 2, 0, 0,
-           (SCM obj, SCM slot_name),
-           "Return @code{#t} if @var{obj} has a slot named @var{slot_name}.")
-#define FUNC_NAME s_scm_slot_exists_p
-{
-  SCM class;
-
-  SCM_VALIDATE_INSTANCE (1, obj);
-  SCM_VALIDATE_SYMBOL (2, slot_name);
-  TEST_CHANGE_CLASS (obj, class);
-
-  return test_slot_existence (class, obj, slot_name);
-}
-#undef FUNC_NAME
-
-
-/******************************************************************************
- *
- * %allocate-instance (the low level instance allocation primitive)
- *
- ******************************************************************************/
-
-static void clear_method_cache (SCM);
-
-SCM_DEFINE (scm_sys_allocate_instance, "%allocate-instance", 2, 0, 0,
-           (SCM class, SCM initargs),
-           "Create a new instance of class @var{class} and initialize it\n"
-           "from the arguments @var{initargs}.")
-#define FUNC_NAME s_scm_sys_allocate_instance
-{
-  SCM obj;
-  scm_t_signed_bits n, i;
-  SCM layout;
-
-  SCM_VALIDATE_CLASS (1, class);
-
-  /* FIXME: duplicates some of scm_make_struct. */
-
-  n = SCM_I_INUM (SCM_SLOT (class, scm_si_nfields));
-  obj = scm_i_alloc_struct (SCM_STRUCT_DATA (class), n);
-
-  layout = SCM_VTABLE_LAYOUT (class);
-
-  /* Set all SCM-holding slots to unbound */
-  for (i = 0; i < n; i++)
-    {
-      scm_t_wchar c = scm_i_symbol_ref (layout, i*2);
-      if (c == 'p')
-        SCM_STRUCT_DATA (obj)[i] = SCM_UNPACK (SCM_GOOPS_UNBOUND);
-      else if (c == 's')
-        SCM_STRUCT_DATA (obj)[i] = SCM_UNPACK (obj);
-      else
-        SCM_STRUCT_DATA (obj)[i] = 0;
-    }
-
-  if (SCM_CLASS_FLAGS (class) & SCM_CLASSF_PURE_GENERIC)
-    clear_method_cache (obj);
-
-  return obj;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_sys_set_object_setter_x, "%set-object-setter!", 2, 0, 0,
-           (SCM obj, SCM setter),
-           "")
-#define FUNC_NAME s_scm_sys_set_object_setter_x
-{
-  SCM_ASSERT (SCM_STRUCTP (obj)
-              && (SCM_OBJ_CLASS_FLAGS (obj) & SCM_CLASSF_PURE_GENERIC),
-             obj,
-             SCM_ARG1,
-             FUNC_NAME);
-  SCM_SET_GENERIC_SETTER (obj, setter);
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-/******************************************************************************
- *
- * %modify-instance (used by change-class to modify in place)
- *
- ******************************************************************************/
-
-SCM_DEFINE (scm_sys_modify_instance, "%modify-instance", 2, 0, 0,
-           (SCM old, SCM new),
-           "")
-#define FUNC_NAME s_scm_sys_modify_instance
-{
-  SCM_VALIDATE_INSTANCE (1, old);
-  SCM_VALIDATE_INSTANCE (2, new);
-
-  /* Exchange the data contained in old and new. We exchange rather than
-   * scratch the old value with new to be correct with GC.
-   * See "Class redefinition protocol above".
-   */
-  SCM_CRITICAL_SECTION_START;
-  {
-    scm_t_bits word0, word1;
-    word0 = SCM_CELL_WORD_0 (old);
-    word1 = SCM_CELL_WORD_1 (old);
-    SCM_SET_CELL_WORD_0 (old, SCM_CELL_WORD_0 (new));
-    SCM_SET_CELL_WORD_1 (old, SCM_CELL_WORD_1 (new));
-    SCM_SET_CELL_WORD_0 (new, word0);
-    SCM_SET_CELL_WORD_1 (new, word1);
-  }
-  SCM_CRITICAL_SECTION_END;
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_sys_modify_class, "%modify-class", 2, 0, 0,
-           (SCM old, SCM new),
-           "")
-#define FUNC_NAME s_scm_sys_modify_class
-{
-  SCM_VALIDATE_CLASS (1, old);
-  SCM_VALIDATE_CLASS (2, new);
-
-  SCM_CRITICAL_SECTION_START;
-  {
-    scm_t_bits word0, word1;
-    word0 = SCM_CELL_WORD_0 (old);
-    word1 = SCM_CELL_WORD_1 (old);
-    SCM_SET_CELL_WORD_0 (old, SCM_CELL_WORD_0 (new));
-    SCM_SET_CELL_WORD_1 (old, SCM_CELL_WORD_1 (new));
-    SCM_STRUCT_DATA (old)[scm_vtable_index_self] = SCM_UNPACK (old);
-    SCM_SET_CELL_WORD_0 (new, word0);
-    SCM_SET_CELL_WORD_1 (new, word1);
-    SCM_STRUCT_DATA (new)[scm_vtable_index_self] = SCM_UNPACK (new);
-  }
-  SCM_CRITICAL_SECTION_END;
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_sys_invalidate_class, "%invalidate-class", 1, 0, 0,
-           (SCM class),
-           "")
-#define FUNC_NAME s_scm_sys_invalidate_class
-{
-  SCM_VALIDATE_CLASS (1, class);
-  SCM_CLEAR_CLASS_FLAGS (class, SCM_CLASSF_GOOPS_VALID);
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-/* When instances change class, they finally get a new body, but
- * before that, they go through purgatory in hell.  Odd as it may
- * seem, this data structure saves us from eternal suffering in
- * infinite recursions.
- */
-
-static scm_t_bits **hell;
-static long n_hell = 1;                /* one place for the evil one himself */
-static long hell_size = 4;
-static SCM hell_mutex;
-
-static long
-burnin (SCM o)
-{
-  long i;
-  for (i = 1; i < n_hell; ++i)
-    if (SCM_STRUCT_DATA (o) == hell[i])
-      return i;
-  return 0;
-}
-
-static void
-go_to_hell (void *o)
-{
-  SCM obj = *(SCM*)o;
-  scm_lock_mutex (hell_mutex);
-  if (n_hell >= hell_size)
-    {
-      hell_size *= 2;
-      hell = scm_realloc (hell, hell_size * sizeof(*hell));
-    }
-  hell[n_hell++] = SCM_STRUCT_DATA (obj);
-  scm_unlock_mutex (hell_mutex);
-}
-
-static void
-go_to_heaven (void *o)
-{
-  SCM obj = *(SCM*)o;
-  scm_lock_mutex (hell_mutex);
-  hell[burnin (obj)] = hell[--n_hell];
-  scm_unlock_mutex (hell_mutex);
-}
-
-
-SCM_SYMBOL (scm_sym_change_class, "change-class");
-
-static SCM
-purgatory (SCM obj, SCM new_class)
-{
-  return scm_call_2 (SCM_VARIABLE_REF (var_change_class), obj, new_class);
-}
-
-/* This function calls the generic function change-class for all
- * instances which aren't currently undergoing class change.
- */
-
-void
-scm_change_object_class (SCM obj, SCM old_class SCM_UNUSED, SCM new_class)
-{
-  if (!burnin (obj))
-    {
-      scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
-      scm_dynwind_rewind_handler (go_to_hell, &obj, SCM_F_WIND_EXPLICITLY);
-      scm_dynwind_unwind_handler (go_to_heaven, &obj, SCM_F_WIND_EXPLICITLY);
-      purgatory (obj, new_class);
-      scm_dynwind_end ();
-    }
-}
-
-/******************************************************************************
- *
- *   GGGG                FFFFF
- *  G                    F
- *  G  GG                FFF
- *  G   G                F
- *   GGG  E N E R I C    F    U N C T I O N S
- *
- * This implementation provides
- *     - generic functions (with class specializers)
- *     - multi-methods
- *     - next-method
- *     - a hard-coded MOP for standard gf, which can be overloaded for non-std gf
- *
- ******************************************************************************/
-
-SCM_KEYWORD (k_name, "name");
-
-SCM_GLOBAL_SYMBOL (scm_sym_args, "args");
-
-SCM_SYMBOL (sym_delayed_compile, "delayed-compile");
-
-static SCM delayed_compile_var;
-
-static void
-init_delayed_compile_var (void)
-{
-  delayed_compile_var
-    = scm_c_private_lookup ("oop goops dispatch", "delayed-compile");
-}
-
-static SCM
-make_dispatch_procedure (SCM gf)
-{
-  static scm_i_pthread_once_t once = SCM_I_PTHREAD_ONCE_INIT;
-  scm_i_pthread_once (&once, init_delayed_compile_var);
-
-  return scm_call_1 (scm_variable_ref (delayed_compile_var), gf);
-}
-
-static void
-clear_method_cache (SCM gf)
-{
-  SCM_SET_GENERIC_DISPATCH_PROCEDURE (gf, make_dispatch_procedure (gf));
-  SCM_CLEAR_GENERIC_EFFECTIVE_METHODS (gf);
-}
-
-SCM_DEFINE (scm_sys_invalidate_method_cache_x, "%invalidate-method-cache!", 1, 0, 0,
-           (SCM gf),
-           "")
-#define FUNC_NAME s_scm_sys_invalidate_method_cache_x
-{
-  SCM_ASSERT (SCM_PUREGENERICP (gf), gf, SCM_ARG1, FUNC_NAME);
-  clear_method_cache (gf);
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_generic_capability_p, "generic-capability?", 1, 0, 0,
-           (SCM proc),
-           "")
-#define FUNC_NAME s_scm_generic_capability_p
-{
-  SCM_ASSERT (scm_is_true (scm_procedure_p (proc)),
-             proc, SCM_ARG1, FUNC_NAME);
-  return (SCM_PRIMITIVE_GENERIC_P (proc) ? SCM_BOOL_T : SCM_BOOL_F);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_enable_primitive_generic_x, "enable-primitive-generic!", 0, 0, 1,
-           (SCM subrs),
-           "")
-#define FUNC_NAME s_scm_enable_primitive_generic_x
-{
-  SCM_VALIDATE_REST_ARGUMENT (subrs);
-  while (!scm_is_null (subrs))
-    {
-      SCM subr = SCM_CAR (subrs);
-      SCM_ASSERT (SCM_PRIMITIVE_GENERIC_P (subr), subr, SCM_ARGn, FUNC_NAME);
-      SCM_SET_SUBR_GENERIC (subr,
-                            scm_make (scm_list_3 (scm_class_generic,
-                                                  k_name,
-                                                  SCM_SUBR_NAME (subr))));
-      subrs = SCM_CDR (subrs);
-    }
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_set_primitive_generic_x, "set-primitive-generic!", 2, 0, 0,
-           (SCM subr, SCM generic),
-           "")
-#define FUNC_NAME s_scm_set_primitive_generic_x
-{
-  SCM_ASSERT (SCM_PRIMITIVE_GENERIC_P (subr), subr, SCM_ARG1, FUNC_NAME);
-  SCM_ASSERT (SCM_PUREGENERICP (generic), generic, SCM_ARG2, FUNC_NAME);
-  SCM_SET_SUBR_GENERIC (subr, generic);
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_primitive_generic_generic, "primitive-generic-generic", 1, 0, 0,
-           (SCM subr),
-           "")
-#define FUNC_NAME s_scm_primitive_generic_generic
-{
-  if (SCM_PRIMITIVE_GENERIC_P (subr))
-    {
-      if (!SCM_UNPACK (*SCM_SUBR_GENERIC (subr)))
-       scm_enable_primitive_generic_x (scm_list_1 (subr));
-      return *SCM_SUBR_GENERIC (subr);
-    }
-  SCM_WRONG_TYPE_ARG (SCM_ARG1, subr);
-}
-#undef FUNC_NAME
-
-typedef struct t_extension {
-  struct t_extension *next;
-  SCM extended;
-  SCM extension;
-} t_extension;
-
-
-/* Hint for `scm_gc_malloc ()' et al. when allocating `t_extension'
-   objects.  */
-static const char extension_gc_hint[] = "GOOPS extension";
-
-static t_extension *extensions = 0;
-
-void
-scm_c_extend_primitive_generic (SCM extended, SCM extension)
-{
-  if (goops_loaded_p)
-    {
-      SCM gf, gext;
-      if (!SCM_UNPACK (*SCM_SUBR_GENERIC (extended)))
-       scm_enable_primitive_generic_x (scm_list_1 (extended));
-      gf = *SCM_SUBR_GENERIC (extended);
-      gext = scm_call_2 (SCM_VARIABLE_REF (scm_var_make_extended_generic),
-                        gf,
-                        SCM_SUBR_NAME (extension));
-      SCM_SET_SUBR_GENERIC (extension, gext);
-    }
-  else
-    {
-      t_extension *e = scm_gc_malloc (sizeof (t_extension),
-                                     extension_gc_hint);
-      t_extension **loc = &extensions;
-      /* Make sure that extensions are placed before their own
-       * extensions in the extensions list.  O(N^2) algorithm, but
-       * extensions of primitive generics are rare.
-       */
-      while (*loc && !scm_is_eq (extension, (*loc)->extended))
-       loc = &(*loc)->next;
-      e->next = *loc;
-      e->extended = extended;
-      e->extension = extension;
-      *loc = e;
-    }
-}
-
-static void
-setup_extended_primitive_generics ()
-{
-  while (extensions)
-    {
-      t_extension *e = extensions;
-      scm_c_extend_primitive_generic (e->extended, e->extension);
-      extensions = e->next;
-    }
-}
-
-/* Dirk:FIXME:: In all of these scm_wta_dispatch_* routines it is
- * assumed that 'gf' is zero if uninitialized.  It would be cleaner if
- * some valid SCM value like SCM_BOOL_F or SCM_UNDEFINED were chosen.
- */
-
-SCM
-scm_wta_dispatch_0 (SCM gf, const char *subr)
-{
-  if (!SCM_UNPACK (gf))
-    scm_error_num_args_subr (subr);
-
-  return scm_call_0 (gf);
-}
-
-SCM
-scm_wta_dispatch_1 (SCM gf, SCM a1, int pos, const char *subr)
-{
-  if (!SCM_UNPACK (gf))
-    scm_wrong_type_arg (subr, pos, a1);
-
-  return scm_call_1 (gf, a1);
-}
-
-SCM
-scm_wta_dispatch_2 (SCM gf, SCM a1, SCM a2, int pos, const char *subr)
-{
-  if (!SCM_UNPACK (gf))
-    scm_wrong_type_arg (subr, pos, (pos == SCM_ARG1) ? a1 : a2);
-
-  return scm_call_2 (gf, a1, a2);
-}
-
-SCM
-scm_wta_dispatch_n (SCM gf, SCM args, int pos, const char *subr)
-{
-  if (!SCM_UNPACK (gf))
-    scm_wrong_type_arg (subr, pos, scm_list_ref (args, scm_from_int (pos)));
-
-  return scm_apply_0 (gf, args);
-}
-
-/******************************************************************************
- *
- * Protocol for calling a generic fumction
- * This protocol is roughly equivalent to (parameter are a little bit different
- * for efficiency reasons):
- *
- *     + apply-generic (gf args)
- *             + compute-applicable-methods (gf args ...)
- *                     + sort-applicable-methods (methods args)
- *             + apply-methods (gf methods args)
- *
- * apply-methods calls make-next-method to build the "continuation" of a a
- * method.  Applying a next-method will call apply-next-method which in
- * turn will call  apply again to call effectively the following method.
- *
- ******************************************************************************/
-
-static int
-applicablep (SCM actual, SCM formal)
-{
-  /* We already know that the cpl is well formed. */
-  return scm_is_true (scm_c_memq (formal, SCM_SLOT (actual, scm_si_cpl)));
-}
-
-static int
-more_specificp (SCM m1, SCM m2, SCM const *targs)
-{
-  register SCM s1, s2;
-  register long i;
-  /*
-   * Note:
-   *   m1 and m2 can have != length (i.e. one can be one element longer than the
-   * other when we have a dotted parameter list). For instance, with the call
-   *   (M 1)
-   * with
-   *   (define-method M (a . l) ....)
-   *   (define-method M (a) ....)
-   *
-   * we consider that the second method is more specific.
-   *
-   * BTW, targs is an array of types. We don't need it's size since
-   * we already know that m1 and m2 are applicable (no risk to go past
-   * the end of this array).
-   *
-   */
-  for (i=0, s1=SPEC_OF(m1), s2=SPEC_OF(m2); ; i++, s1=SCM_CDR(s1), s2=SCM_CDR(s2)) {
-    if (scm_is_null(s1)) return 1;
-    if (scm_is_null(s2)) return 0;
-    if (!scm_is_eq (SCM_CAR(s1), SCM_CAR(s2))) {
-      register SCM l, cs1 = SCM_CAR(s1), cs2 = SCM_CAR(s2);
-
-      for (l = SCM_SLOT (targs[i], scm_si_cpl);   ; l = SCM_CDR(l)) {
-       if (scm_is_eq (cs1, SCM_CAR (l)))
-         return 1;
-       if (scm_is_eq (cs2, SCM_CAR (l)))
-         return 0;
-      }
-      return 0;/* should not occur! */
-    }
-  }
-  return 0; /* should not occur! */
-}
-
-#define BUFFSIZE 32            /* big enough for most uses */
-
-static SCM
-scm_i_vector2list (SCM l, long len)
-{
-  long j;
-  SCM z = scm_c_make_vector (len, SCM_UNDEFINED);
-
-  for (j = 0; j < len; j++, l = SCM_CDR (l)) {
-    SCM_SIMPLE_VECTOR_SET (z, j, SCM_CAR (l));
-  }
-  return z;
-}
-
-static SCM
-sort_applicable_methods (SCM method_list, long size, SCM const *targs)
-{
-  long i, j, incr;
-  SCM *v, vector = SCM_EOL;
-  SCM buffer[BUFFSIZE];
-  SCM save = method_list;
-  scm_t_array_handle handle;
-
-  /* For reasonably sized method_lists we can try to avoid all the
-   * consing and reorder the list in place...
-   * This idea is due to David McClain <Dave_McClain@msn.com>
-   */
-  if (size <= BUFFSIZE)
-    {
-      for (i = 0;  i < size; i++)
-       {
-         buffer[i]   = SCM_CAR (method_list);
-         method_list = SCM_CDR (method_list);
-       }
-      v = buffer;
-    }
-  else
-    {
-      /* Too many elements in method_list to keep everything locally */
-      vector = scm_i_vector2list (save, size);
-      v = scm_vector_writable_elements (vector, &handle, NULL, NULL);
-    }
-
-  /* Use a simple shell sort since it is generally faster than qsort on
-   * small vectors (which is probably mostly the case when we have to
-   * sort a list of applicable methods).
-   */
-  for (incr = size / 2; incr; incr /= 2)
-    {
-      for (i = incr; i < size; i++)
-       {
-         for (j = i - incr; j >= 0; j -= incr)
-           {
-             if (more_specificp (v[j], v[j+incr], targs))
-               break;
-             else
-               {
-                 SCM tmp = v[j + incr];
-                 v[j + incr] = v[j];
-                 v[j] = tmp;
-               }
-           }
-       }
-    }
-
-  if (size <= BUFFSIZE)
-    {
-      /* We did it in locally, so restore the original list (reordered) in-place */
-      for (i = 0, method_list = save; i < size; i++, v++)
-       {
-         SCM_SETCAR (method_list, *v);
-         method_list = SCM_CDR (method_list);
-       }
-      return save;
-    }
-
-  /* If we are here, that's that we did it the hard way... */
-  scm_array_handle_release (&handle);
-  return scm_vector_to_list (vector);
-}
-
-SCM
-scm_compute_applicable_methods (SCM gf, SCM args, long len, int find_method_p)
-{
-  register long i;
-  long count = 0;
-  SCM l, fl, applicable = SCM_EOL;
-  SCM save = args;
-  SCM buffer[BUFFSIZE];
-  SCM const *types;
-  SCM *p;
-  SCM tmp = SCM_EOL;
-  scm_t_array_handle handle;
-
-  /* Build the list of arguments types */
-  if (len >= BUFFSIZE) 
-    {
-      tmp = scm_c_make_vector (len, SCM_UNDEFINED);
-      types = p = scm_vector_writable_elements (tmp, &handle, NULL, NULL);
-
-    /*
-      note that we don't have to work to reset the generation
-      count. TMP is a new vector anyway, and it is found
-      conservatively.
-    */
-    }
-  else
-    types = p = buffer;
-
-  for (  ; !scm_is_null (args); args = SCM_CDR (args))
-    *p++ = scm_class_of (SCM_CAR (args));
-  
-  /* Build a list of all applicable methods */
-  for (l = scm_generic_function_methods (gf); !scm_is_null (l); l = SCM_CDR (l))
-    {
-      fl = SPEC_OF (SCM_CAR (l));
-      for (i = 0; ; i++, fl = SCM_CDR (fl))
-       {
-         if (SCM_INSTANCEP (fl)
-             /* We have a dotted argument list */
-             || (i >= len && scm_is_null (fl)))
-           {   /* both list exhausted */
-             applicable = scm_cons (SCM_CAR (l), applicable);
-             count     += 1;
-             break;
-           }
-         if (i >= len
-             || scm_is_null (fl)
-             || !applicablep (types[i], SCM_CAR (fl)))
-           break;
-       }
-    }
-
-  if (len >= BUFFSIZE)
-      scm_array_handle_release (&handle);
-
-  if (count == 0)
-    {
-      if (find_method_p)
-       return SCM_BOOL_F;
-      scm_call_2 (SCM_VARIABLE_REF (var_no_applicable_method), gf, save);
-      /* if we are here, it's because no-applicable-method hasn't signaled an error */
-      return SCM_BOOL_F;
-    }
-
-  return (count == 1
-         ? applicable
-         : sort_applicable_methods (applicable, count, types));
-}
-
-#if 0
-SCM_PROC (s_sys_compute_applicable_methods, "%compute-applicable-methods", 2, 0, 0, scm_sys_compute_applicable_methods);
-#endif
-
-static const char s_sys_compute_applicable_methods[] = "%compute-applicable-methods";
-
-SCM
-scm_sys_compute_applicable_methods (SCM gf, SCM args)
-#define FUNC_NAME s_sys_compute_applicable_methods
-{
-  long n;
-  SCM_VALIDATE_GENERIC (1, gf);
-  n = scm_ilength (args);
-  SCM_ASSERT (n >= 0, args, SCM_ARG2, FUNC_NAME);
-  return scm_compute_applicable_methods (gf, args, n, 1);
-}
-#undef FUNC_NAME
-
-SCM_SYMBOL (sym_compute_applicable_methods, "compute-applicable-methods");
-SCM_VARIABLE_INIT (var_compute_applicable_methods, "compute-applicable-methods",
-                   scm_c_define_gsubr (s_sys_compute_applicable_methods, 2, 0, 0,
-                                       scm_sys_compute_applicable_methods));
-
-/******************************************************************************
- *
- * A simple make (which will be redefined later in Scheme)
- * This version handles only creation of gf, methods and classes (no instances)
- *
- * Since this code will disappear when Goops will be fully booted,
- * no precaution is taken to be efficient.
- *
- ******************************************************************************/
-
-SCM_KEYWORD (k_setter,         "setter");
-SCM_KEYWORD (k_specializers,   "specializers");
-SCM_KEYWORD (k_procedure,      "procedure");
-SCM_KEYWORD (k_formals,                "formals");
-SCM_KEYWORD (k_body,           "body");
-SCM_KEYWORD (k_make_procedure, "make-procedure");
-SCM_KEYWORD (k_dsupers,                "dsupers");
-SCM_KEYWORD (k_slots,          "slots");
-SCM_KEYWORD (k_gf,             "generic-function");
-
-SCM_DEFINE (scm_make, "make",  0, 0, 1,
-           (SCM args),
-           "Make a new object.  @var{args} must contain the class and\n"
-           "all necessary initialization information.")
-#define FUNC_NAME s_scm_make
-{
-  SCM class, z;
-  long len = scm_ilength (args);
-
-  if (len <= 0 || (len & 1) == 0)
-    SCM_WRONG_NUM_ARGS ();
-
-  class = SCM_CAR(args);
-  args  = SCM_CDR(args);
-
-  if (scm_is_eq (class, scm_class_generic)
-      || scm_is_eq (class, scm_class_accessor))
-    {
-      z = scm_make_struct (class, SCM_INUM0,
-                           scm_list_4 (SCM_BOOL_F,
-                                       SCM_EOL,
-                                      SCM_INUM0,
-                                      SCM_EOL));
-      scm_set_procedure_property_x (z, scm_sym_name,
-                                   scm_get_keyword (k_name,
-                                                    args,
-                                                    SCM_BOOL_F));
-      clear_method_cache (z);
-      if (scm_is_eq (class, scm_class_accessor))
-       {
-         SCM setter = scm_get_keyword (k_setter, args, SCM_BOOL_F);
-         if (scm_is_true (setter))
-           scm_sys_set_object_setter_x (z, setter);
-       }
-    }
-  else
-    {
-      z = scm_sys_allocate_instance (class, args);
-
-      if (scm_is_eq (class, scm_class_method)
-         || scm_is_eq (class, scm_class_accessor_method))
-       {
-         SCM_SET_SLOT (z, scm_si_generic_function,
-           scm_i_get_keyword (k_gf,
-                              args,
-                              len - 1,
-                              SCM_BOOL_F,
-                              FUNC_NAME));
-         SCM_SET_SLOT (z, scm_si_specializers,
-           scm_i_get_keyword (k_specializers,
-                              args,
-                              len - 1,
-                              SCM_EOL,
-                              FUNC_NAME));
-         SCM_SET_SLOT (z, scm_si_procedure,
-           scm_i_get_keyword (k_procedure,
-                              args,
-                              len - 1,
-                              SCM_BOOL_F,
-                              FUNC_NAME));
-         SCM_SET_SLOT (z, scm_si_formals,
-           scm_i_get_keyword (k_formals,
-                              args,
-                              len - 1,
-                              SCM_EOL,
-                              FUNC_NAME));
-         SCM_SET_SLOT (z, scm_si_body,
-           scm_i_get_keyword (k_body,
-                              args,
-                              len - 1,
-                              SCM_EOL,
-                              FUNC_NAME));
-         SCM_SET_SLOT (z, scm_si_make_procedure,
-           scm_i_get_keyword (k_make_procedure,
-                              args,
-                              len - 1,
-                              SCM_BOOL_F,
-                              FUNC_NAME));
-       }
-      else
-       {
-         /* In all the others case, make a new class .... No instance here */
-         SCM_SET_SLOT (z, scm_vtable_index_name,
-           scm_i_get_keyword (k_name,
-                              args,
-                              len - 1,
-                              scm_from_latin1_symbol ("???"),
-                              FUNC_NAME));
-         SCM_SET_SLOT (z, scm_si_direct_supers,
-           scm_i_get_keyword (k_dsupers,
-                              args,
-                              len - 1,
-                              SCM_EOL,
-                              FUNC_NAME));
-         SCM_SET_SLOT (z, scm_si_direct_slots,
-           scm_i_get_keyword (k_slots,
-                              args,
-                              len - 1,
-                              SCM_EOL,
-                              FUNC_NAME));
-       }
-    }
-  return z;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_find_method, "find-method", 0, 0, 1,
-           (SCM l),
-           "")
-#define FUNC_NAME s_scm_find_method
-{
-  SCM gf;
-  long len = scm_ilength (l);
-
-  if (len == 0)
-    SCM_WRONG_NUM_ARGS ();
-
-  gf = SCM_CAR(l); l = SCM_CDR(l);
-  SCM_VALIDATE_GENERIC (1, gf);
-  if (scm_is_null (SCM_SLOT (gf, scm_si_methods)))
-    SCM_MISC_ERROR ("no methods for generic ~S", scm_list_1 (gf));
-
-  return scm_compute_applicable_methods (gf, l, len - 1, 1);
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_sys_method_more_specific_p, "%method-more-specific?", 3, 0, 0,
-           (SCM m1, SCM m2, SCM targs),
-           "Return true if method @var{m1} is more specific than @var{m2} "
-           "given the argument types (classes) listed in @var{targs}.")
-#define FUNC_NAME s_scm_sys_method_more_specific_p
-{
-  SCM l, v, result;
-  SCM *v_elts;
-  long i, len, m1_specs, m2_specs;
-  scm_t_array_handle handle;
-
-  SCM_VALIDATE_METHOD (1, m1);
-  SCM_VALIDATE_METHOD (2, m2);
-
-  len = scm_ilength (targs);
-  m1_specs = scm_ilength (SPEC_OF (m1));
-  m2_specs = scm_ilength (SPEC_OF (m2));
-  SCM_ASSERT ((len >= m1_specs) || (len >= m2_specs),
-             targs, SCM_ARG3, FUNC_NAME);
-
-  /* Verify that all the arguments of TARGS are classes and place them
-     in a vector.  */
-
-  v = scm_c_make_vector (len, SCM_EOL);
-  v_elts = scm_vector_writable_elements (v, &handle, NULL, NULL);
-
-  for (i = 0, l = targs;
-       i < len && scm_is_pair (l);
-       i++, l = SCM_CDR (l))
-    {
-      SCM_ASSERT (SCM_CLASSP (SCM_CAR (l)), targs, SCM_ARG3, FUNC_NAME);
-      v_elts[i] = SCM_CAR (l);
-    }
-  result = more_specificp (m1, m2, v_elts) ? SCM_BOOL_T: SCM_BOOL_F;
-
-  scm_array_handle_release (&handle);
-
-  return result;
-}
-#undef FUNC_NAME
-
-
-
-/******************************************************************************
- *
- * Initializations
- *
- ******************************************************************************/
-
-/* Munge the CPL of C in place such that BEFORE appears before AFTER,
-   assuming that currently the reverse is true.  Recalculate slots and
-   associated getters-n-setters.  */
-static void
-fix_cpl (SCM c, SCM before, SCM after)
-{
-  SCM cpl = SCM_SLOT (c, scm_si_cpl);
-  SCM ls = scm_c_memq (after, cpl);
-  SCM tail;
-
-  if (scm_is_false (ls))
-    /* if this condition occurs, fix_cpl should not be applied this way */
-    abort ();
-
-  tail = scm_delq1_x (before, SCM_CDR (ls));
-  SCM_SETCAR (ls, before);
-  SCM_SETCDR (ls, scm_cons (after, tail));
-  {
-    SCM dslots = SCM_SLOT (c, scm_si_direct_slots);
-    SCM slots = build_slots_list (maplist (dslots), cpl);
-    SCM g_n_s = compute_getters_n_setters (slots);
-    SCM_SET_SLOT (c, scm_si_slots, slots);
-    SCM_SET_SLOT (c, scm_si_getters_n_setters, g_n_s);
-  }
-}
-
-
-static void
-make_stdcls (SCM *var, char *name, SCM meta, SCM super, SCM slots)
-{
-   SCM tmp = scm_from_utf8_symbol (name);
-
-   *var = scm_basic_make_class (meta, tmp,
-                                scm_is_pair (super) ? super : scm_list_1 (super),
-                                slots);
-   scm_module_define (scm_module_goops, tmp, *var);
-}
-
-
-SCM_KEYWORD (k_slot_definition, "slot-definition");
-
-static void
-create_standard_classes (void)
-{
-  SCM slots;
-  SCM method_slots = scm_list_n (scm_from_latin1_symbol ("generic-function"),
-                                scm_from_latin1_symbol ("specializers"),
-                                sym_procedure,
-                                scm_from_latin1_symbol ("formals"),
-                                scm_from_latin1_symbol ("body"),
-                                scm_from_latin1_symbol ("make-procedure"),
-                                 SCM_UNDEFINED);
-  SCM amethod_slots = scm_list_1 (scm_list_3 (scm_from_latin1_symbol ("slot-definition"),
-                                             k_init_keyword,
-                                             k_slot_definition));
-  SCM gf_slots = scm_list_4 (scm_from_latin1_symbol ("methods"),
-                            scm_list_3 (scm_from_latin1_symbol ("n-specialized"),
-                                        k_init_value,
-                                        SCM_INUM0),
-                            scm_list_3 (scm_from_latin1_symbol ("extended-by"),
-                                        k_init_value,
-                                        SCM_EOL),
-                             scm_from_latin1_symbol ("effective-methods"));
-  SCM setter_slots = scm_list_1 (sym_setter);
-  SCM egf_slots = scm_list_1 (scm_list_3 (scm_from_latin1_symbol ("extends"),
-                                         k_init_value,
-                                         SCM_EOL));
-  /* Foreign class slot classes */
-  make_stdcls (&scm_class_foreign_slot,           "<foreign-slot>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_protected,      "<protected-slot>",
-              scm_class_class, scm_class_foreign_slot,    SCM_EOL);
-  make_stdcls (&scm_class_hidden,         "<hidden-slot>",
-              scm_class_class, scm_class_foreign_slot,    SCM_EOL);
-  make_stdcls (&scm_class_opaque,         "<opaque-slot>",
-              scm_class_class, scm_class_foreign_slot,    SCM_EOL);
-  make_stdcls (&scm_class_read_only,      "<read-only-slot>",
-              scm_class_class, scm_class_foreign_slot,    SCM_EOL);
-  make_stdcls (&scm_class_self,                   "<self-slot>",
-              scm_class_class, scm_class_read_only,       SCM_EOL);
-  make_stdcls (&scm_class_protected_opaque, "<protected-opaque-slot>",
-              scm_class_class,
-              scm_list_2 (scm_class_protected, scm_class_opaque),
-              SCM_EOL);
-  make_stdcls (&scm_class_protected_hidden, "<protected-hidden-slot>",
-              scm_class_class,
-              scm_list_2 (scm_class_protected, scm_class_hidden),
-              SCM_EOL);
-  make_stdcls (&scm_class_protected_read_only, "<protected-read-only-slot>",
-              scm_class_class,
-              scm_list_2 (scm_class_protected, scm_class_read_only),
-              SCM_EOL);
-  make_stdcls (&scm_class_scm,            "<scm-slot>",
-              scm_class_class, scm_class_protected, SCM_EOL);
-  make_stdcls (&scm_class_int,            "<int-slot>",
-              scm_class_class, scm_class_foreign_slot,    SCM_EOL);
-  make_stdcls (&scm_class_float,          "<float-slot>",
-              scm_class_class, scm_class_foreign_slot,    SCM_EOL);
-  make_stdcls (&scm_class_double,         "<double-slot>",
-              scm_class_class, scm_class_foreign_slot,    SCM_EOL);
-
-  /* Continue initialization of class <class> */
-
-  slots = build_class_class_slots ();
-  SCM_SET_SLOT (scm_class_class, scm_si_direct_slots, slots);
-  SCM_SET_SLOT (scm_class_class, scm_si_slots, slots);
-  SCM_SET_SLOT (scm_class_class, scm_si_getters_n_setters,
-               compute_getters_n_setters (slots));
-
-  /* scm_class_generic functions classes */
-  make_stdcls (&scm_class_procedure_class, "<procedure-class>",
-              scm_class_class, scm_class_class, SCM_EOL);
-  make_stdcls (&scm_class_applicable_struct_class,    "<applicable-struct-class>",
-              scm_class_class, scm_class_procedure_class, SCM_EOL);
-  SCM_SET_VTABLE_FLAGS (scm_class_applicable_struct_class, SCM_VTABLE_FLAG_APPLICABLE_VTABLE);
-  make_stdcls (&scm_class_method,         "<method>",
-              scm_class_class, scm_class_object,          method_slots);
-  make_stdcls (&scm_class_accessor_method, "<accessor-method>",
-              scm_class_class, scm_class_method,   amethod_slots);
-  make_stdcls (&scm_class_applicable,     "<applicable>",
-              scm_class_class, scm_class_top, SCM_EOL);
-  make_stdcls (&scm_class_applicable_struct,      "<applicable-struct>",
-              scm_class_applicable_struct_class,
-              scm_list_2 (scm_class_object, scm_class_applicable),
-              scm_list_1 (sym_procedure));
-  make_stdcls (&scm_class_generic,        "<generic>",
-              scm_class_applicable_struct_class, scm_class_applicable_struct,   gf_slots);
-  SCM_SET_CLASS_FLAGS (scm_class_generic, SCM_CLASSF_PURE_GENERIC);
-  make_stdcls (&scm_class_extended_generic, "<extended-generic>",
-              scm_class_applicable_struct_class, scm_class_generic, egf_slots);
-  SCM_SET_CLASS_FLAGS (scm_class_extended_generic, SCM_CLASSF_PURE_GENERIC);
-  make_stdcls (&scm_class_generic_with_setter, "<generic-with-setter>",
-              scm_class_applicable_struct_class, scm_class_generic, setter_slots);
-  SCM_SET_CLASS_FLAGS (scm_class_generic_with_setter, SCM_CLASSF_PURE_GENERIC);
-  make_stdcls (&scm_class_accessor,       "<accessor>",
-              scm_class_applicable_struct_class, scm_class_generic_with_setter, SCM_EOL);
-  SCM_SET_CLASS_FLAGS (scm_class_accessor, SCM_CLASSF_PURE_GENERIC);
-  make_stdcls (&scm_class_extended_generic_with_setter,
-              "<extended-generic-with-setter>",
-              scm_class_applicable_struct_class,
-              scm_list_2 (scm_class_extended_generic,
-                           scm_class_generic_with_setter),
-              SCM_EOL);
-  SCM_SET_CLASS_FLAGS (scm_class_extended_generic_with_setter,
-                      SCM_CLASSF_PURE_GENERIC);
-  make_stdcls (&scm_class_extended_accessor, "<extended-accessor>",
-              scm_class_applicable_struct_class,
-              scm_list_2 (scm_class_accessor,
-                          scm_class_extended_generic_with_setter),
-              SCM_EOL);
-  /* <extended-generic> is misplaced.  */
-  fix_cpl (scm_class_extended_accessor,
-          scm_class_extended_generic, scm_class_generic_with_setter);
-  SCM_SET_CLASS_FLAGS (scm_class_extended_accessor, SCM_CLASSF_PURE_GENERIC);
-
-  /* Primitive types classes */
-  make_stdcls (&scm_class_boolean,        "<boolean>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_char,                   "<char>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_list,                   "<list>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_pair,                   "<pair>",
-              scm_class_class, scm_class_list,            SCM_EOL);
-  make_stdcls (&scm_class_null,                   "<null>",
-              scm_class_class, scm_class_list,            SCM_EOL);
-  make_stdcls (&scm_class_string,         "<string>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_symbol,         "<symbol>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_vector,         "<vector>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_foreign,            "<foreign>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_hashtable,          "<hashtable>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_fluid,              "<fluid>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_dynamic_state,      "<dynamic-state>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_frame,              "<frame>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_vm_cont,            "<vm-continuation>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_bytevector,         "<bytevector>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_uvec,               "<uvec>",
-              scm_class_class, class_bytevector,          SCM_EOL);
-  make_stdcls (&class_array,              "<array>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&class_bitvector,           "<bitvector>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_number,         "<number>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_complex,        "<complex>",
-              scm_class_class, scm_class_number,          SCM_EOL);
-  make_stdcls (&scm_class_real,                   "<real>",
-              scm_class_class, scm_class_complex,         SCM_EOL);
-  make_stdcls (&scm_class_integer,        "<integer>",
-              scm_class_class, scm_class_real,            SCM_EOL);
-  make_stdcls (&scm_class_fraction,       "<fraction>",
-              scm_class_class, scm_class_real,            SCM_EOL);
-  make_stdcls (&scm_class_keyword,        "<keyword>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_unknown,        "<unknown>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_procedure,      "<procedure>",
-              scm_class_procedure_class, scm_class_applicable, SCM_EOL);
-  make_stdcls (&scm_class_primitive_generic, "<primitive-generic>",
-              scm_class_procedure_class, scm_class_procedure, SCM_EOL);
-  make_stdcls (&scm_class_port,                   "<port>",
-              scm_class_class, scm_class_top,             SCM_EOL);
-  make_stdcls (&scm_class_input_port,     "<input-port>",
-              scm_class_class, scm_class_port,            SCM_EOL);
-  make_stdcls (&scm_class_output_port,    "<output-port>",
-              scm_class_class, scm_class_port,            SCM_EOL);
-  make_stdcls (&scm_class_input_output_port, "<input-output-port>",
-              scm_class_class,
-              scm_list_2 (scm_class_input_port, scm_class_output_port),
-              SCM_EOL);
-}
-
-/**********************************************************************
- *
- * Smob classes
- *
- **********************************************************************/
-
-static SCM
-make_class_from_template (char const *template, char const *type_name, SCM supers, int applicablep)
-{
-  SCM name;
-  if (type_name)
-    {
-      char buffer[100];
-      sprintf (buffer, template, type_name);
-      name = scm_from_utf8_symbol (buffer);
-    }
-  else
-    name = SCM_GOOPS_UNBOUND;
-
-  return scm_basic_make_class (applicablep ? scm_class_procedure_class : scm_class_class,
-                               name, supers, SCM_EOL);
-}
-
-static SCM
-make_class_from_symbol (SCM type_name_sym, SCM supers, int applicablep)
-{
-  SCM name;
-
-  if (scm_is_true (type_name_sym))
-    {
-      name = scm_string_append (scm_list_3 (scm_from_locale_string ("<"),
-                                           scm_symbol_to_string (type_name_sym),
-                                           scm_from_locale_string (">")));
-      name = scm_string_to_symbol (name);
-    }
-  else
-    name = SCM_GOOPS_UNBOUND;
-
-  return scm_basic_make_class (applicablep ? scm_class_procedure_class : scm_class_class,
-                               name, supers, SCM_EOL);
-}
-
-SCM
-scm_make_extended_class (char const *type_name, int applicablep)
-{
-  return make_class_from_template ("<%s>",
-                                  type_name,
-                                  scm_list_1 (applicablep
-                                              ? scm_class_applicable
-                                              : scm_class_top),
-                                  applicablep);
-}
-
-static SCM
-scm_make_extended_class_from_symbol (SCM type_name_sym, int applicablep)
-{
-  return make_class_from_symbol (type_name_sym,
-                                scm_list_1 (applicablep
-                                            ? scm_class_applicable
-                                            : scm_class_top),
-                                applicablep);
-}
-
-void
-scm_i_inherit_applicable (SCM c)
-{
-  if (!SCM_SUBCLASSP (c, scm_class_applicable))
-    {
-      SCM dsupers = SCM_SLOT (c, scm_si_direct_supers);
-      SCM cpl = SCM_SLOT (c, scm_si_cpl);
-      /* patch scm_class_applicable into direct-supers */
-      SCM top = scm_c_memq (scm_class_top, dsupers);
-      if (scm_is_false (top))
-       dsupers = scm_append (scm_list_2 (dsupers,
-                                         scm_list_1 (scm_class_applicable)));
-      else
-       {
-         SCM_SETCAR (top, scm_class_applicable);
-         SCM_SETCDR (top, scm_cons (scm_class_top, SCM_CDR (top)));
-       }
-      SCM_SET_SLOT (c, scm_si_direct_supers, dsupers);
-      /* patch scm_class_applicable into cpl */
-      top = scm_c_memq (scm_class_top, cpl);
-      if (scm_is_false (top))
-       abort ();
-      else
-       {
-         SCM_SETCAR (top, scm_class_applicable);
-         SCM_SETCDR (top, scm_cons (scm_class_top, SCM_CDR (top)));
-       }
-      /* add class to direct-subclasses of scm_class_applicable */
-      SCM_SET_SLOT (scm_class_applicable,
-                   scm_si_direct_subclasses,
-                   scm_cons (c, SCM_SLOT (scm_class_applicable,
-                                          scm_si_direct_subclasses)));
-    }
-}
-
-static void
-create_smob_classes (void)
-{
-  long i;
-
-  for (i = 0; i < SCM_I_MAX_SMOB_TYPE_COUNT; ++i)
-    scm_smob_class[i] = SCM_BOOL_F;
-
-  for (i = 0; i < scm_numsmob; ++i)
-    if (scm_is_false (scm_smob_class[i]))
-      scm_smob_class[i] = scm_make_extended_class (SCM_SMOBNAME (i),
-                                                  scm_smobs[i].apply != 0);
-}
-
-void
-scm_make_port_classes (long ptobnum, char *type_name)
-{
-  SCM c, class = make_class_from_template ("<%s-port>",
-                                          type_name,
-                                          scm_list_1 (scm_class_port),
-                                          0);
-  scm_port_class[SCM_IN_PCLASS_INDEX + ptobnum]
-    = make_class_from_template ("<%s-input-port>",
-                               type_name,
-                               scm_list_2 (class, scm_class_input_port),
-                               0);
-  scm_port_class[SCM_OUT_PCLASS_INDEX + ptobnum]
-    = make_class_from_template ("<%s-output-port>",
-                               type_name,
-                               scm_list_2 (class, scm_class_output_port),
-                               0);
-  scm_port_class[SCM_INOUT_PCLASS_INDEX + ptobnum]
-    = c
-    = make_class_from_template ("<%s-input-output-port>",
-                               type_name,
-                               scm_list_2 (class, scm_class_input_output_port),
-                               0);
-  /* Patch cpl (since this tree is too complex for the C level compute-cpl) */
-  SCM_SET_SLOT (c, scm_si_cpl,
-               scm_cons2 (c, class, SCM_SLOT (scm_class_input_output_port, scm_si_cpl)));
-}
-
-static void
-create_port_classes (void)
-{
-  long i;
-
-  for (i = scm_c_num_port_types () - 1; i >= 0; i--)
-    scm_make_port_classes (i, SCM_PTOBNAME (i));
-}
-
-static SCM
-make_struct_class (void *closure SCM_UNUSED,
-                  SCM vtable, SCM data, SCM prev SCM_UNUSED)
-{
-  if (scm_is_false (data))
-    scm_i_define_class_for_vtable (vtable);
-  return SCM_UNSPECIFIED;
-}
-
-static void
-create_struct_classes (void)
-{
-  /* FIXME: take the vtable_class_map while initializing goops?  */
-  scm_internal_hash_fold (make_struct_class, 0, SCM_BOOL_F,
-                          vtable_class_map);
-}
-
-/**********************************************************************
- *
- * C interface
- *
- **********************************************************************/
-
-void
-scm_load_goops ()
-{
-  if (!goops_loaded_p)
-    scm_c_resolve_module ("oop goops");
-}
-
-
-SCM_SYMBOL (sym_o, "o");
-SCM_SYMBOL (sym_x, "x");
-
-SCM_KEYWORD (k_accessor, "accessor");
-SCM_KEYWORD (k_getter, "getter");
-
-SCM
-scm_ensure_accessor (SCM name)
-{
-  SCM var, gf;
-
-  var = scm_module_variable (scm_current_module (), name);
-  if (SCM_VARIABLEP (var) && !SCM_UNBNDP (SCM_VARIABLE_REF (var)))
-    gf = SCM_VARIABLE_REF (var);
-  else
-    gf = SCM_BOOL_F;
-
-  if (!SCM_IS_A_P (gf, scm_class_accessor))
-    {
-      gf = scm_make (scm_list_3 (scm_class_generic, k_name, name));
-      gf = scm_make (scm_list_5 (scm_class_accessor,
-                                k_name, name, k_setter, gf));
-    }
-
-  return gf;
-}
-
-#ifdef GUILE_DEBUG
-/*
- * Debugging utilities
- */
-
-SCM_DEFINE (scm_pure_generic_p, "pure-generic?", 1, 0, 0,
-           (SCM obj),
-           "Return @code{#t} if @var{obj} is a pure generic.")
-#define FUNC_NAME s_scm_pure_generic_p
-{
-  return scm_from_bool (SCM_PUREGENERICP (obj));
-}
-#undef FUNC_NAME
-
-#endif /* GUILE_DEBUG */
-
-/*
- * Initialization
- */
-
-SCM_DEFINE (scm_sys_goops_loaded, "%goops-loaded", 0, 0, 0,
-           (),
-           "Announce that GOOPS is loaded and perform initialization\n"
-           "on the C level which depends on the loaded GOOPS modules.")
-#define FUNC_NAME s_scm_sys_goops_loaded
-{
-  goops_loaded_p = 1;
-  var_compute_applicable_methods =
-    scm_module_variable (scm_module_goops, sym_compute_applicable_methods);
-  var_slot_unbound =
-    scm_module_variable (scm_module_goops, sym_slot_unbound);
-  var_slot_missing =
-    scm_module_variable (scm_module_goops, sym_slot_missing);
-  var_compute_cpl =
-    scm_module_variable (scm_module_goops, sym_compute_cpl);
-  var_no_applicable_method =
-    scm_module_variable (scm_module_goops, sym_no_applicable_method);
-  var_change_class =
-    scm_module_variable (scm_module_goops, sym_change_class);
-  setup_extended_primitive_generics ();
-  return SCM_UNSPECIFIED;
-}
-#undef FUNC_NAME
-
-SCM scm_module_goops;
-
-SCM
-scm_init_goops_builtins (void)
-{
-  scm_module_goops = scm_current_module ();
-
-  goops_rstate = scm_c_make_rstate ("GOOPS", 5);
-
-#include "libguile/goops.x"
-
-  hell = scm_calloc (hell_size * sizeof (*hell));
-  hell_mutex = scm_make_mutex ();
-
-  create_basic_classes ();
-  create_standard_classes ();
-  create_smob_classes ();
-  create_struct_classes ();
-  create_port_classes ();
-
-  {
-    SCM name = scm_from_latin1_symbol ("no-applicable-method");
-    scm_no_applicable_method =
-      scm_make (scm_list_3 (scm_class_generic, k_name, name));
-    scm_module_define (scm_module_goops, name, scm_no_applicable_method);
-  }
-
-  return SCM_UNSPECIFIED;
-}
-
-void
-scm_init_goops ()
-{
-  scm_c_define_gsubr ("%init-goops-builtins", 0, 0, 0,
-                     scm_init_goops_builtins);
-}
-
-/*
-  Local Variables:
-  c-file-style: "gnu"
-  End:
-*/
+/* Copyright (C) 1998,1999,2000,2001,2002,2003,2004,2008,2009,2010,2011,2012,2013,2014,2015
+ * 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 3 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 software is a derivative work of other copyrighted softwares; the
+ * copyright notices of these softwares are placed in the file COPYRIGHTS
+ *
+ * This file is based upon stklos.c from the STk distribution by
+ * Erick Gallesio <eg@unice.fr>.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "libguile/_scm.h"
+#include "libguile/async.h"
+#include "libguile/chars.h"
+#include "libguile/dynwind.h"
+#include "libguile/eval.h"
+#include "libguile/gsubr.h"
+#include "libguile/hashtab.h"
+#include "libguile/keywords.h"
+#include "libguile/macros.h"
+#include "libguile/modules.h"
+#include "libguile/ports.h"
+#include "libguile/procprop.h"
+#include "libguile/programs.h"
+#include "libguile/smob.h"
+#include "libguile/strings.h"
+#include "libguile/strports.h"
+#include "libguile/vectors.h"
+
+#include "libguile/validate.h"
+#include "libguile/goops.h"
+
+/* Port classes */
+#define SCM_IN_PCLASS_INDEX       0
+#define SCM_OUT_PCLASS_INDEX      SCM_I_MAX_PORT_TYPE_COUNT
+#define SCM_INOUT_PCLASS_INDEX    (2 * SCM_I_MAX_PORT_TYPE_COUNT)
+
+/* Objects have identity, so references to classes and instances are by
+   value, not by reference.  Redefinition of a class or modification of
+   an instance causes in-place update; you can think of GOOPS as
+   building in its own indirection, and for that reason referring to
+   GOOPS values by variable reference is unnecessary.
+
+   References to ordinary procedures is by reference (by variable),
+   though, as in the rest of Guile.  */
+
+SCM_KEYWORD (k_name, "name");
+SCM_KEYWORD (k_setter, "setter");
+SCM_SYMBOL (sym_redefined, "redefined");
+SCM_GLOBAL_SYMBOL (scm_sym_args, "args");
+
+static int goops_loaded_p = 0;
+
+static SCM var_make_standard_class = SCM_BOOL_F;
+static SCM var_change_class = SCM_BOOL_F;
+static SCM var_make = SCM_BOOL_F;
+static SCM var_inherit_applicable = SCM_BOOL_F;
+static SCM var_class_name = SCM_BOOL_F;
+static SCM var_class_direct_supers = SCM_BOOL_F;
+static SCM var_class_direct_slots = SCM_BOOL_F;
+static SCM var_class_direct_subclasses = SCM_BOOL_F;
+static SCM var_class_direct_methods = SCM_BOOL_F;
+static SCM var_class_precedence_list = SCM_BOOL_F;
+static SCM var_class_slots = SCM_BOOL_F;
+
+static SCM var_generic_function_methods = SCM_BOOL_F;
+static SCM var_method_generic_function = SCM_BOOL_F;
+static SCM var_method_specializers = SCM_BOOL_F;
+static SCM var_method_procedure = SCM_BOOL_F;
+
+static SCM var_slot_ref = SCM_BOOL_F;
+static SCM var_slot_set_x = SCM_BOOL_F;
+static SCM var_slot_bound_p = SCM_BOOL_F;
+static SCM var_slot_exists_p = SCM_BOOL_F;
+
+/* These variables are filled in by the object system when loaded. */
+static SCM class_boolean, class_char, class_pair;
+static SCM class_procedure, class_string, class_symbol;
+static SCM class_primitive_generic;
+static SCM class_vector, class_null;
+static SCM class_integer, class_real, class_complex, class_fraction;
+static SCM class_unknown;
+static SCM class_top, class_object, class_class;
+static SCM class_applicable;
+static SCM class_applicable_struct, class_applicable_struct_with_setter;
+static SCM class_generic, class_generic_with_setter;
+static SCM class_accessor;
+static SCM class_extended_generic, class_extended_generic_with_setter;
+static SCM class_extended_accessor;
+static SCM class_method;
+static SCM class_accessor_method;
+static SCM class_procedure_class;
+static SCM class_applicable_struct_class;
+static SCM class_applicable_struct_with_setter_class;
+static SCM class_number, class_list;
+static SCM class_keyword;
+static SCM class_port, class_input_output_port;
+static SCM class_input_port, class_output_port;
+static SCM class_foreign_slot;
+static SCM class_self, class_protected;
+static SCM class_hidden, class_opaque, class_read_only;
+static SCM class_protected_hidden, class_protected_opaque, class_protected_read_only;
+static SCM class_scm;
+static SCM class_int, class_float, class_double;
+
+static SCM class_foreign;
+static SCM class_hashtable;
+static SCM class_fluid;
+static SCM class_dynamic_state;
+static SCM class_frame;
+static SCM class_vm_cont;
+static SCM class_bytevector;
+static SCM class_uvec;
+static SCM class_array;
+static SCM class_bitvector;
+
+static SCM vtable_class_map = SCM_BOOL_F;
+
+/* Port classes.  Allocate 3 times the maximum number of port types so that
+   input ports, output ports, and in/out ports can be stored at different
+   offsets.  See `SCM_IN_PCLASS_INDEX' et al.  */
+SCM scm_i_port_class[3 * SCM_I_MAX_PORT_TYPE_COUNT];
+
+/* SMOB classes.  */
+SCM scm_i_smob_class[SCM_I_MAX_SMOB_TYPE_COUNT];
+
+SCM scm_module_goops;
+
+static SCM scm_sys_make_vtable_vtable (SCM layout);
+static SCM scm_sys_init_layout_x (SCM class, SCM layout);
+static SCM scm_sys_clear_fields_x (SCM obj, SCM unbound);
+static SCM scm_sys_goops_early_init (void);
+static SCM scm_sys_goops_loaded (void);
+
+
+\f
+
+SCM_DEFINE (scm_sys_make_vtable_vtable, "%make-vtable-vtable", 1, 0, 0,
+            (SCM layout),
+           "")
+#define FUNC_NAME s_scm_sys_make_vtable_vtable
+{
+  return scm_i_make_vtable_vtable (layout);
+}
+#undef FUNC_NAME
+
+SCM
+scm_make_standard_class (SCM meta, SCM name, SCM dsupers, SCM dslots)
+{
+  return scm_call_4 (scm_variable_ref (var_make_standard_class),
+                     meta, name, dsupers, dslots);
+}
+
+SCM_DEFINE (scm_sys_init_layout_x, "%init-layout!", 2, 0, 0,
+           (SCM class, SCM layout),
+           "")
+#define FUNC_NAME s_scm_sys_init_layout_x
+{
+  SCM_VALIDATE_INSTANCE (1, class);
+  SCM_ASSERT (!scm_is_symbol (SCM_VTABLE_LAYOUT (class)), class, 1, FUNC_NAME);
+  SCM_VALIDATE_STRING (2, layout);
+
+  SCM_SET_VTABLE_LAYOUT (class, scm_make_struct_layout (layout));
+  scm_i_struct_inherit_vtable_magic (SCM_CLASS_OF (class), class);
+  SCM_SET_CLASS_FLAGS (class, SCM_CLASSF_GOOPS_OR_VALID);
+
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+\f
+
+/* 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 class_integer;
+
+    case scm_tc3_imm24:
+      if (SCM_CHARP (x))
+       return class_char;
+      else if (scm_is_bool (x))
+        return class_boolean;
+      else if (scm_is_null (x))
+        return class_null;
+      else
+        return class_unknown;
+
+    case scm_tc3_cons:
+      switch (SCM_TYP7 (x))
+       {
+       case scm_tcs_cons_nimcar:
+         return class_pair;
+       case scm_tc7_symbol:
+         return class_symbol;
+       case scm_tc7_vector:
+       case scm_tc7_wvect:
+         return class_vector;
+       case scm_tc7_pointer:
+         return class_foreign;
+       case scm_tc7_hashtable:
+         return class_hashtable;
+       case scm_tc7_fluid:
+         return class_fluid;
+       case scm_tc7_dynamic_state:
+         return class_dynamic_state;
+        case scm_tc7_frame:
+         return class_frame;
+        case scm_tc7_keyword:
+         return class_keyword;
+        case scm_tc7_vm_cont:
+         return class_vm_cont;
+       case scm_tc7_bytevector:
+          if (SCM_BYTEVECTOR_ELEMENT_TYPE (x) == SCM_ARRAY_ELEMENT_TYPE_VU8)
+            return class_bytevector;
+          else
+            return class_uvec;
+       case scm_tc7_array:
+          return class_array;
+       case scm_tc7_bitvector:
+          return class_bitvector;
+       case scm_tc7_string:
+         return class_string;
+        case scm_tc7_number:
+          switch SCM_TYP16 (x) {
+          case scm_tc16_big:
+            return class_integer;
+          case scm_tc16_real:
+            return class_real;
+          case scm_tc16_complex:
+            return class_complex;
+         case scm_tc16_fraction:
+           return class_fraction;
+          }
+       case scm_tc7_program:
+         if (SCM_PROGRAM_IS_PRIMITIVE_GENERIC (x)
+              && SCM_UNPACK (*SCM_SUBR_GENERIC (x)))
+           return class_primitive_generic;
+         else
+           return class_procedure;
+
+       case scm_tc7_smob:
+         {
+           scm_t_bits type = SCM_TYP16 (x);
+           if (type != scm_tc16_port_with_ps)
+             return scm_i_smob_class[SCM_TC2SMOBNUM (type)];
+           x = SCM_PORT_WITH_PS_PORT (x);
+           /* fall through to ports */
+         }
+       case scm_tc7_port:
+         return scm_i_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_struct:
+         if (SCM_OBJ_CLASS_FLAGS (x) & SCM_CLASSF_GOOPS_VALID)
+            /* A GOOPS object with a valid class.  */
+           return SCM_CLASS_OF (x);
+         else if (SCM_OBJ_CLASS_FLAGS (x) & SCM_CLASSF_GOOPS)
+            /* A GOOPS object whose class might have been redefined.  */
+           {
+              SCM class = SCM_CLASS_OF (x);
+              SCM new_class = scm_slot_ref (class, sym_redefined);
+              if (!scm_is_false (new_class))
+               scm_change_object_class (x, class, new_class);
+              /* Re-load class from instance.  */
+             return SCM_CLASS_OF (x);
+           }
+         else
+            return scm_i_define_class_for_vtable (SCM_CLASS_OF (x));
+       default:
+         if (scm_is_pair (x))
+           return class_pair;
+         else
+           return class_unknown;
+       }
+
+    case scm_tc3_struct:
+    case scm_tc3_tc7_1:
+    case scm_tc3_tc7_2:
+      /* case scm_tc3_unused: */
+      /* Never reached */
+      break;
+    }
+  return class_unknown;
+}
+#undef FUNC_NAME
+
+
+\f
+
+SCM_DEFINE (scm_instance_p, "instance?", 1, 0, 0,
+           (SCM obj),
+           "Return @code{#t} if @var{obj} is an instance.")
+#define FUNC_NAME s_scm_instance_p
+{
+  return scm_from_bool (SCM_INSTANCEP (obj));
+}
+#undef FUNC_NAME
+
+int
+scm_is_generic (SCM x)
+{
+  return SCM_INSTANCEP (x) && SCM_SUBCLASSP (SCM_CLASS_OF (x), class_generic);
+}
+
+int
+scm_is_method (SCM x)
+{
+  return SCM_INSTANCEP (x) && SCM_SUBCLASSP (SCM_CLASS_OF (x), class_method);
+}
+
+
+\f
+
+SCM
+scm_class_name (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_class_name), obj);
+}
+
+SCM
+scm_class_direct_supers (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_class_direct_supers), obj);
+}
+
+SCM
+scm_class_direct_slots (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_class_direct_slots), obj);
+}
+
+SCM
+scm_class_direct_subclasses (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_class_direct_subclasses), obj);
+}
+
+SCM
+scm_class_direct_methods (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_class_direct_methods), obj);
+}
+
+SCM
+scm_class_precedence_list (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_class_precedence_list), obj);
+}
+
+SCM
+scm_class_slots (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_class_slots), obj);
+}
+
+
+\f
+
+SCM_DEFINE (scm_generic_function_name, "generic-function-name", 1, 0, 0,
+            (SCM obj),
+           "Return the name of the generic function @var{obj}.")
+#define FUNC_NAME s_scm_generic_function_name
+{
+  SCM_VALIDATE_GENERIC (1, obj);
+  return scm_procedure_property (obj, scm_sym_name);
+}
+#undef FUNC_NAME
+
+SCM
+scm_generic_function_methods (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_generic_function_methods), obj);
+}
+
+SCM
+scm_method_generic_function (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_method_generic_function), obj);
+}
+
+SCM
+scm_method_specializers (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_method_specializers), obj);
+}
+
+SCM
+scm_method_procedure (SCM obj)
+{
+  return scm_call_1 (scm_variable_ref (var_method_procedure), obj);
+}
+
+
+\f
+
+SCM
+scm_slot_ref (SCM obj, SCM slot_name)
+{
+  return scm_call_2 (scm_variable_ref (var_slot_ref), obj, slot_name);
+}
+
+SCM
+scm_slot_set_x (SCM obj, SCM slot_name, SCM value)
+{
+  return scm_call_3 (scm_variable_ref (var_slot_set_x), obj, slot_name, value);
+}
+
+SCM
+scm_slot_bound_p (SCM obj, SCM slot_name)
+{
+  return scm_call_2 (scm_variable_ref (var_slot_bound_p), obj, slot_name);
+}
+
+SCM
+scm_slot_exists_p (SCM obj, SCM slot_name)
+{
+  return scm_call_2 (scm_variable_ref (var_slot_exists_p), obj, slot_name);
+}
+
+
+\f
+
+SCM_DEFINE (scm_sys_clear_fields_x, "%clear-fields!", 2, 0, 0,
+           (SCM obj, SCM unbound),
+            "")
+#define FUNC_NAME s_scm_sys_clear_fields_x
+{
+  scm_t_signed_bits n, i;
+  SCM vtable, layout;
+
+  SCM_VALIDATE_STRUCT (1, obj);
+  vtable = SCM_STRUCT_VTABLE (obj);
+
+  n = SCM_STRUCT_DATA_REF (vtable, scm_vtable_index_size);
+  layout = SCM_VTABLE_LAYOUT (vtable);
+
+  /* Set all SCM-holding slots to the GOOPS unbound value.  */
+  for (i = 0; i < n; i++)
+    if (scm_i_symbol_ref (layout, i*2) == 'p')
+      SCM_STRUCT_SLOT_SET (obj, i, unbound);
+
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+\f
+
+SCM_DEFINE (scm_sys_modify_instance, "%modify-instance", 2, 0, 0,
+           (SCM old, SCM new),
+           "Used by change-class to modify objects in place.")
+#define FUNC_NAME s_scm_sys_modify_instance
+{
+  SCM_VALIDATE_INSTANCE (1, old);
+  SCM_VALIDATE_INSTANCE (2, new);
+
+  /* Exchange the data contained in old and new. We exchange rather than
+   * scratch the old value with new to be correct with GC.
+   * See "Class redefinition protocol above".
+   */
+  SCM_CRITICAL_SECTION_START;
+  {
+    scm_t_bits word0, word1;
+    word0 = SCM_CELL_WORD_0 (old);
+    word1 = SCM_CELL_WORD_1 (old);
+    SCM_SET_CELL_WORD_0 (old, SCM_CELL_WORD_0 (new));
+    SCM_SET_CELL_WORD_1 (old, SCM_CELL_WORD_1 (new));
+    SCM_SET_CELL_WORD_0 (new, word0);
+    SCM_SET_CELL_WORD_1 (new, word1);
+  }
+  SCM_CRITICAL_SECTION_END;
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_sys_modify_class, "%modify-class", 2, 0, 0,
+           (SCM old, SCM new),
+           "")
+#define FUNC_NAME s_scm_sys_modify_class
+{
+  SCM_VALIDATE_CLASS (1, old);
+  SCM_VALIDATE_CLASS (2, new);
+
+  SCM_CRITICAL_SECTION_START;
+  {
+    scm_t_bits word0, word1;
+    word0 = SCM_CELL_WORD_0 (old);
+    word1 = SCM_CELL_WORD_1 (old);
+    SCM_SET_CELL_WORD_0 (old, SCM_CELL_WORD_0 (new));
+    SCM_SET_CELL_WORD_1 (old, SCM_CELL_WORD_1 (new));
+    SCM_STRUCT_DATA (old)[scm_vtable_index_self] = SCM_UNPACK (old);
+    SCM_SET_CELL_WORD_0 (new, word0);
+    SCM_SET_CELL_WORD_1 (new, word1);
+    SCM_STRUCT_DATA (new)[scm_vtable_index_self] = SCM_UNPACK (new);
+  }
+  SCM_CRITICAL_SECTION_END;
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+/* When instances change class, they finally get a new body, but
+ * before that, they go through purgatory in hell.  Odd as it may
+ * seem, this data structure saves us from eternal suffering in
+ * infinite recursions.
+ */
+
+static scm_t_bits **hell;
+static long n_hell = 1;                /* one place for the evil one himself */
+static long hell_size = 4;
+static SCM hell_mutex;
+
+static long
+burnin (SCM o)
+{
+  long i;
+  for (i = 1; i < n_hell; ++i)
+    if (SCM_STRUCT_DATA (o) == hell[i])
+      return i;
+  return 0;
+}
+
+static void
+go_to_hell (void *o)
+{
+  SCM obj = *(SCM*)o;
+  scm_lock_mutex (hell_mutex);
+  if (n_hell >= hell_size)
+    {
+      hell_size *= 2;
+      hell = scm_realloc (hell, hell_size * sizeof(*hell));
+    }
+  hell[n_hell++] = SCM_STRUCT_DATA (obj);
+  scm_unlock_mutex (hell_mutex);
+}
+
+static void
+go_to_heaven (void *o)
+{
+  SCM obj = *(SCM*)o;
+  scm_lock_mutex (hell_mutex);
+  hell[burnin (obj)] = hell[--n_hell];
+  scm_unlock_mutex (hell_mutex);
+}
+
+
+static SCM
+purgatory (SCM obj, SCM new_class)
+{
+  return scm_call_2 (SCM_VARIABLE_REF (var_change_class), obj, new_class);
+}
+
+/* This function calls the generic function change-class for all
+ * instances which aren't currently undergoing class change.
+ */
+
+void
+scm_change_object_class (SCM obj, SCM old_class SCM_UNUSED, SCM new_class)
+{
+  if (!burnin (obj))
+    {
+      scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
+      scm_dynwind_rewind_handler (go_to_hell, &obj, SCM_F_WIND_EXPLICITLY);
+      scm_dynwind_unwind_handler (go_to_heaven, &obj, SCM_F_WIND_EXPLICITLY);
+      purgatory (obj, new_class);
+      scm_dynwind_end ();
+    }
+}
+
+
+\f
+
+/* Primitive generics: primitives that can dispatch to generics if their
+   arguments fail to apply.  */
+
+SCM_DEFINE (scm_generic_capability_p, "generic-capability?", 1, 0, 0,
+           (SCM proc),
+           "")
+#define FUNC_NAME s_scm_generic_capability_p
+{
+  SCM_ASSERT (scm_is_true (scm_procedure_p (proc)),
+             proc, SCM_ARG1, FUNC_NAME);
+  return (SCM_PRIMITIVE_GENERIC_P (proc) ? SCM_BOOL_T : SCM_BOOL_F);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_enable_primitive_generic_x, "enable-primitive-generic!", 0, 0, 1,
+           (SCM subrs),
+           "")
+#define FUNC_NAME s_scm_enable_primitive_generic_x
+{
+  SCM_VALIDATE_REST_ARGUMENT (subrs);
+  while (!scm_is_null (subrs))
+    {
+      SCM subr = SCM_CAR (subrs);
+      SCM_ASSERT (SCM_PRIMITIVE_GENERIC_P (subr), subr, SCM_ARGn, FUNC_NAME);
+      SCM_SET_SUBR_GENERIC (subr,
+                            scm_make (scm_list_3 (class_generic,
+                                                  k_name,
+                                                  SCM_SUBR_NAME (subr))));
+      subrs = SCM_CDR (subrs);
+    }
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_set_primitive_generic_x, "set-primitive-generic!", 2, 0, 0,
+           (SCM subr, SCM generic),
+           "")
+#define FUNC_NAME s_scm_set_primitive_generic_x
+{
+  SCM_ASSERT (SCM_PRIMITIVE_GENERIC_P (subr), subr, SCM_ARG1, FUNC_NAME);
+  SCM_ASSERT (SCM_GENERICP (generic), generic, SCM_ARG2, FUNC_NAME);
+  SCM_SET_SUBR_GENERIC (subr, generic);
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_primitive_generic_generic, "primitive-generic-generic", 1, 0, 0,
+           (SCM subr),
+           "")
+#define FUNC_NAME s_scm_primitive_generic_generic
+{
+  if (SCM_PRIMITIVE_GENERIC_P (subr))
+    {
+      if (!SCM_UNPACK (*SCM_SUBR_GENERIC (subr)))
+       scm_enable_primitive_generic_x (scm_list_1 (subr));
+      return *SCM_SUBR_GENERIC (subr);
+    }
+  SCM_WRONG_TYPE_ARG (SCM_ARG1, subr);
+}
+#undef FUNC_NAME
+
+SCM
+scm_wta_dispatch_0 (SCM gf, const char *subr)
+{
+  if (!SCM_UNPACK (gf))
+    scm_error_num_args_subr (subr);
+
+  return scm_call_0 (gf);
+}
+
+SCM
+scm_wta_dispatch_1 (SCM gf, SCM a1, int pos, const char *subr)
+{
+  if (!SCM_UNPACK (gf))
+    scm_wrong_type_arg (subr, pos, a1);
+
+  return scm_call_1 (gf, a1);
+}
+
+SCM
+scm_wta_dispatch_2 (SCM gf, SCM a1, SCM a2, int pos, const char *subr)
+{
+  if (!SCM_UNPACK (gf))
+    scm_wrong_type_arg (subr, pos, (pos == SCM_ARG1) ? a1 : a2);
+
+  return scm_call_2 (gf, a1, a2);
+}
+
+SCM
+scm_wta_dispatch_n (SCM gf, SCM args, int pos, const char *subr)
+{
+  if (!SCM_UNPACK (gf))
+    scm_wrong_type_arg (subr, pos, scm_list_ref (args, scm_from_int (pos)));
+
+  return scm_apply_0 (gf, args);
+}
+
+
+\f
+
+SCM
+scm_make (SCM args)
+{
+  return scm_apply_0 (scm_variable_ref (var_make), args);
+}
+
+
+\f
+
+/* SMOB, struct, and port classes.  */
+
+static SCM
+make_class_name (const char *prefix, const char *type_name, const char *suffix)
+{
+  if (!type_name)
+    type_name = "";
+  return scm_string_to_symbol (scm_string_append
+                               (scm_list_3 (scm_from_utf8_string (prefix),
+                                            scm_from_utf8_string (type_name),
+                                            scm_from_utf8_string (suffix))));
+}
+
+SCM
+scm_make_extended_class (char const *type_name, int applicablep)
+{
+  SCM name, meta, supers;
+
+  name = make_class_name ("<", type_name, ">");
+  meta = class_class;
+
+  if (applicablep)
+    supers = scm_list_1 (class_applicable);
+  else
+    supers = scm_list_1 (class_top);
+
+  return scm_make_standard_class (meta, name, supers, SCM_EOL);
+}
+
+void
+scm_i_inherit_applicable (SCM c)
+{
+  scm_call_1 (scm_variable_ref (var_inherit_applicable), c);
+}
+
+static void
+create_smob_classes (void)
+{
+  long i;
+
+  for (i = 0; i < SCM_I_MAX_SMOB_TYPE_COUNT; ++i)
+    scm_i_smob_class[i] = SCM_BOOL_F;
+
+  for (i = 0; i < scm_numsmob; ++i)
+    if (scm_is_false (scm_i_smob_class[i]))
+      scm_i_smob_class[i] = scm_make_extended_class (SCM_SMOBNAME (i),
+                                                     scm_smobs[i].apply != 0);
+}
+
+void
+scm_make_port_classes (long ptobnum, char *type_name)
+{
+  SCM name, meta, super, supers;
+
+  meta = class_class;
+
+  name = make_class_name ("<", type_name, "-port>");
+  supers = scm_list_1 (class_port);
+  super = scm_make_standard_class (meta, name, supers, SCM_EOL);
+
+  name = make_class_name ("<", type_name, "-input-port>");
+  supers = scm_list_2 (super, class_input_port);
+  scm_i_port_class[SCM_IN_PCLASS_INDEX + ptobnum]
+    = scm_make_standard_class (meta, name, supers, SCM_EOL);
+
+  name = make_class_name ("<", type_name, "-output-port>");
+  supers = scm_list_2 (super, class_output_port);
+  scm_i_port_class[SCM_OUT_PCLASS_INDEX + ptobnum]
+    = scm_make_standard_class (meta, name, supers, SCM_EOL);
+
+  name = make_class_name ("<", type_name, "-input-output-port>");
+  supers = scm_list_2 (super, class_input_output_port);
+  scm_i_port_class[SCM_INOUT_PCLASS_INDEX + ptobnum]
+    = scm_make_standard_class (meta, name, supers, SCM_EOL);
+}
+
+static void
+create_port_classes (void)
+{
+  long i;
+
+  for (i = scm_c_num_port_types () - 1; i >= 0; i--)
+    scm_make_port_classes (i, SCM_PTOBNAME (i));
+}
+
+SCM
+scm_i_define_class_for_vtable (SCM vtable)
+{
+  SCM class;
+
+  scm_i_pthread_mutex_lock (&scm_i_misc_mutex);
+  if (scm_is_false (vtable_class_map))
+    vtable_class_map = scm_c_make_weak_table (0, SCM_WEAK_TABLE_KIND_KEY);
+  scm_i_pthread_mutex_unlock (&scm_i_misc_mutex);
+
+  if (scm_is_false (scm_struct_vtable_p (vtable)))
+    abort ();
+
+  class = scm_weak_table_refq (vtable_class_map, vtable, SCM_BOOL_F);
+
+  if (scm_is_false (class))
+    {
+      if (SCM_UNPACK (class_class))
+        {
+          SCM name, meta, supers;
+
+          name = SCM_VTABLE_NAME (vtable);
+          if (scm_is_symbol (name))
+            name = scm_string_to_symbol
+              (scm_string_append
+               (scm_list_3 (scm_from_latin1_string ("<"),
+                            scm_symbol_to_string (name),
+                            scm_from_latin1_string (">"))));
+          else
+            name = scm_from_latin1_symbol ("<>");
+
+          if (SCM_STRUCT_VTABLE_FLAG_IS_SET (vtable, SCM_VTABLE_FLAG_SETTER))
+            {
+              meta = class_applicable_struct_with_setter_class;
+              supers = scm_list_1 (class_applicable_struct_with_setter);
+            }
+          else if (SCM_STRUCT_VTABLE_FLAG_IS_SET (vtable,
+                                                  SCM_VTABLE_FLAG_APPLICABLE))
+            {
+              meta = class_applicable_struct_class;
+              supers = scm_list_1 (class_applicable_struct);
+            }
+          else
+            {
+              meta = class_class;
+              supers = scm_list_1 (class_top);
+            }
+
+          return scm_make_standard_class (meta, name, supers, SCM_EOL);
+        }
+      else
+        /* `create_struct_classes' will fill this in later.  */
+        class = SCM_BOOL_F;
+
+      /* Don't worry about races.  This only happens when creating a
+         vtable, which happens by definition in one thread.  */
+      scm_weak_table_putq_x (vtable_class_map, vtable, class);
+    }
+
+  return class;
+}
+
+static SCM
+make_struct_class (void *closure SCM_UNUSED,
+                  SCM vtable, SCM data, SCM prev SCM_UNUSED)
+{
+  if (scm_is_false (data))
+    scm_i_define_class_for_vtable (vtable);
+  return SCM_UNSPECIFIED;
+}
+
+static void
+create_struct_classes (void)
+{
+  /* FIXME: take the vtable_class_map while initializing goops?  */
+  scm_internal_hash_fold (make_struct_class, 0, SCM_BOOL_F,
+                          vtable_class_map);
+}
+
+
+\f
+
+void
+scm_load_goops ()
+{
+  if (!goops_loaded_p)
+    scm_c_resolve_module ("oop goops");
+}
+
+SCM
+scm_ensure_accessor (SCM name)
+{
+  SCM var, gf;
+
+  var = scm_module_variable (scm_current_module (), name);
+  if (SCM_VARIABLEP (var) && !SCM_UNBNDP (SCM_VARIABLE_REF (var)))
+    gf = SCM_VARIABLE_REF (var);
+  else
+    gf = SCM_BOOL_F;
+
+  if (!SCM_IS_A_P (gf, class_accessor))
+    {
+      gf = scm_make (scm_list_3 (class_generic, k_name, name));
+      gf = scm_make (scm_list_5 (class_accessor,
+                                k_name, name, k_setter, gf));
+    }
+
+  return gf;
+}
+
+
+\f
+
+SCM_DEFINE (scm_sys_goops_early_init, "%goops-early-init", 0, 0, 0,
+           (),
+           "")
+#define FUNC_NAME s_scm_sys_goops_early_init
+{
+  var_make_standard_class = scm_c_lookup ("make-standard-class");
+  var_make = scm_c_lookup ("make");
+  var_inherit_applicable = scm_c_lookup ("inherit-applicable!");
+
+  /* For SCM_SUBCLASSP.  */
+  var_class_precedence_list = scm_c_lookup ("class-precedence-list");
+
+  var_slot_ref = scm_c_lookup ("slot-ref");
+  var_slot_set_x = scm_c_lookup ("slot-set!");
+  var_slot_bound_p = scm_c_lookup ("slot-bound?");
+  var_slot_exists_p = scm_c_lookup ("slot-exists?");
+
+  class_class = scm_variable_ref (scm_c_lookup ("<class>"));
+  class_top = scm_variable_ref (scm_c_lookup ("<top>"));
+  class_object = scm_variable_ref (scm_c_lookup ("<object>"));
+
+  class_foreign_slot = scm_variable_ref (scm_c_lookup ("<foreign-slot>"));
+  class_protected = scm_variable_ref (scm_c_lookup ("<protected-slot>"));
+  class_hidden = scm_variable_ref (scm_c_lookup ("<hidden-slot>"));
+  class_opaque = scm_variable_ref (scm_c_lookup ("<opaque-slot>"));
+  class_read_only = scm_variable_ref (scm_c_lookup ("<read-only-slot>"));
+  class_self = scm_variable_ref (scm_c_lookup ("<self-slot>"));
+  class_protected_opaque = scm_variable_ref (scm_c_lookup ("<protected-opaque-slot>"));
+  class_protected_hidden = scm_variable_ref (scm_c_lookup ("<protected-hidden-slot>"));
+  class_protected_read_only = scm_variable_ref (scm_c_lookup ("<protected-read-only-slot>"));
+  class_scm = scm_variable_ref (scm_c_lookup ("<scm-slot>"));
+  class_int = scm_variable_ref (scm_c_lookup ("<int-slot>"));
+  class_float = scm_variable_ref (scm_c_lookup ("<float-slot>"));
+  class_double = scm_variable_ref (scm_c_lookup ("<double-slot>"));
+
+  /* Applicables */
+  class_procedure_class = scm_variable_ref (scm_c_lookup ("<procedure-class>"));
+  class_applicable_struct_class = scm_variable_ref (scm_c_lookup ("<applicable-struct-class>"));
+  class_applicable_struct_with_setter_class =
+    scm_variable_ref (scm_c_lookup ("<applicable-struct-with-setter-class>"));
+
+  class_method = scm_variable_ref (scm_c_lookup ("<method>"));
+  class_accessor_method = scm_variable_ref (scm_c_lookup ("<accessor-method>"));
+  class_applicable = scm_variable_ref (scm_c_lookup ("<applicable>"));
+  class_applicable_struct = scm_variable_ref (scm_c_lookup ("<applicable-struct>"));
+  class_applicable_struct_with_setter = scm_variable_ref (scm_c_lookup ("<applicable-struct-with-setter>"));
+  class_generic = scm_variable_ref (scm_c_lookup ("<generic>"));
+  class_extended_generic = scm_variable_ref (scm_c_lookup ("<extended-generic>"));
+  class_generic_with_setter = scm_variable_ref (scm_c_lookup ("<generic-with-setter>"));
+  class_accessor = scm_variable_ref (scm_c_lookup ("<accessor>"));
+  class_extended_generic_with_setter = scm_variable_ref (scm_c_lookup ("<extended-generic-with-setter>"));
+  class_extended_accessor = scm_variable_ref (scm_c_lookup ("<extended-accessor>"));
+
+  /* Primitive types classes */
+  class_boolean = scm_variable_ref (scm_c_lookup ("<boolean>"));
+  class_char = scm_variable_ref (scm_c_lookup ("<char>"));
+  class_list = scm_variable_ref (scm_c_lookup ("<list>"));
+  class_pair = scm_variable_ref (scm_c_lookup ("<pair>"));
+  class_null = scm_variable_ref (scm_c_lookup ("<null>"));
+  class_string = scm_variable_ref (scm_c_lookup ("<string>"));
+  class_symbol = scm_variable_ref (scm_c_lookup ("<symbol>"));
+  class_vector = scm_variable_ref (scm_c_lookup ("<vector>"));
+  class_foreign = scm_variable_ref (scm_c_lookup ("<foreign>"));
+  class_hashtable = scm_variable_ref (scm_c_lookup ("<hashtable>"));
+  class_fluid = scm_variable_ref (scm_c_lookup ("<fluid>"));
+  class_dynamic_state = scm_variable_ref (scm_c_lookup ("<dynamic-state>"));
+  class_frame = scm_variable_ref (scm_c_lookup ("<frame>"));
+  class_vm_cont = scm_variable_ref (scm_c_lookup ("<vm-continuation>"));
+  class_bytevector = scm_variable_ref (scm_c_lookup ("<bytevector>"));
+  class_uvec = scm_variable_ref (scm_c_lookup ("<uvec>"));
+  class_array = scm_variable_ref (scm_c_lookup ("<array>"));
+  class_bitvector = scm_variable_ref (scm_c_lookup ("<bitvector>"));
+  class_number = scm_variable_ref (scm_c_lookup ("<number>"));
+  class_complex = scm_variable_ref (scm_c_lookup ("<complex>"));
+  class_real = scm_variable_ref (scm_c_lookup ("<real>"));
+  class_integer = scm_variable_ref (scm_c_lookup ("<integer>"));
+  class_fraction = scm_variable_ref (scm_c_lookup ("<fraction>"));
+  class_keyword = scm_variable_ref (scm_c_lookup ("<keyword>"));
+  class_unknown = scm_variable_ref (scm_c_lookup ("<unknown>"));
+  class_procedure = scm_variable_ref (scm_c_lookup ("<procedure>"));
+  class_primitive_generic = scm_variable_ref (scm_c_lookup ("<primitive-generic>"));
+  class_port = scm_variable_ref (scm_c_lookup ("<port>"));
+  class_input_port = scm_variable_ref (scm_c_lookup ("<input-port>"));
+  class_output_port = scm_variable_ref (scm_c_lookup ("<output-port>"));
+  class_input_output_port = scm_variable_ref (scm_c_lookup ("<input-output-port>"));
+
+  create_smob_classes ();
+  create_struct_classes ();
+  create_port_classes ();
+
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_sys_goops_loaded, "%goops-loaded", 0, 0, 0,
+           (),
+           "Announce that GOOPS is loaded and perform initialization\n"
+           "on the C level which depends on the loaded GOOPS modules.")
+#define FUNC_NAME s_scm_sys_goops_loaded
+{
+  goops_loaded_p = 1;
+  var_class_name = scm_c_lookup ("class-name");
+  var_class_direct_supers = scm_c_lookup ("class-direct-supers");
+  var_class_direct_slots = scm_c_lookup ("class-direct-slots");
+  var_class_direct_subclasses = scm_c_lookup ("class-direct-subclasses");
+  var_class_direct_methods = scm_c_lookup ("class-direct-methods");
+  var_class_slots = scm_c_lookup ("class-slots");
+
+  var_generic_function_methods = scm_c_lookup ("generic-function-methods");
+  var_method_generic_function = scm_c_lookup ("method-generic-function");
+  var_method_specializers = scm_c_lookup ("method-specializers");
+  var_method_procedure = scm_c_lookup ("method-procedure");
+
+  var_change_class = scm_c_lookup ("change-class");
+
+#if (SCM_ENABLE_DEPRECATED == 1)
+  scm_init_deprecated_goops ();
+#endif
+
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+static void
+scm_init_goops_builtins (void *unused)
+{
+  scm_module_goops = scm_current_module ();
+
+  hell = scm_calloc (hell_size * sizeof (*hell));
+  hell_mutex = scm_make_mutex ();
+
+#include "libguile/goops.x"
+
+  scm_c_define ("vtable-flag-vtable",
+                scm_from_int (SCM_VTABLE_FLAG_VTABLE));
+  scm_c_define ("vtable-flag-applicable-vtable",
+                scm_from_int (SCM_VTABLE_FLAG_APPLICABLE_VTABLE));
+  scm_c_define ("vtable-flag-setter-vtable",
+                scm_from_int (SCM_VTABLE_FLAG_SETTER_VTABLE));
+  scm_c_define ("vtable-flag-validated",
+                scm_from_int (SCM_VTABLE_FLAG_VALIDATED));
+  scm_c_define ("vtable-flag-goops-class",
+                scm_from_int (SCM_VTABLE_FLAG_GOOPS_CLASS));
+  scm_c_define ("vtable-flag-goops-valid",
+                scm_from_int (SCM_VTABLE_FLAG_GOOPS_VALID));
+}
+
+void
+scm_init_goops ()
+{
+  scm_c_register_extension ("libguile-" SCM_EFFECTIVE_VERSION,
+                            "scm_init_goops_builtins", scm_init_goops_builtins,
+                            NULL);
+}
+
+/*
+  Local Variables:
+  c-file-style: "gnu"
+  End:
+*/