/* Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, * 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 * 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 */ #ifdef HAVE_CONFIG_H # include #endif #include "libguile/__scm.h" #include "libguile/_scm.h" #include "libguile/continuations.h" #include "libguile/eq.h" #include "libguile/expand.h" #include "libguile/list.h" #include "libguile/macros.h" #include "libguile/memoize.h" #include "libguile/modules.h" #include "libguile/srcprop.h" #include "libguile/ports.h" #include "libguile/print.h" #include "libguile/strings.h" #include "libguile/throw.h" #include "libguile/validate.h" #define CAR(x) SCM_CAR(x) #define CDR(x) SCM_CDR(x) #define CAAR(x) SCM_CAAR(x) #define CADR(x) SCM_CADR(x) #define CDAR(x) SCM_CDAR(x) #define CDDR(x) SCM_CDDR(x) #define CADDR(x) SCM_CADDR(x) #define CDDDR(x) SCM_CDDDR(x) #define CADDDR(x) SCM_CADDDR(x) #define VECTOR_REF(v, i) (SCM_SIMPLE_VECTOR_REF (v, i)) #define VECTOR_SET(v, i, x) (SCM_SIMPLE_VECTOR_SET (v, i, x)) #define VECTOR_LENGTH(v) (SCM_SIMPLE_VECTOR_LENGTH (v)) SCM_SYMBOL (sym_case_lambda_star, "case-lambda*"); /* Primitives not exposed to general Scheme. */ static SCM wind; static SCM unwind; static SCM push_fluid; static SCM pop_fluid; static SCM do_wind (SCM in, SCM out) { scm_dynstack_push_dynwind (&SCM_I_CURRENT_THREAD->dynstack, in, out); return SCM_UNSPECIFIED; } static SCM do_unwind (void) { scm_dynstack_pop (&SCM_I_CURRENT_THREAD->dynstack); return SCM_UNSPECIFIED; } static SCM do_push_fluid (SCM fluid, SCM val) { scm_i_thread *thread = SCM_I_CURRENT_THREAD; scm_dynstack_push_fluid (&thread->dynstack, fluid, val, thread->dynamic_state); return SCM_UNSPECIFIED; } static SCM do_pop_fluid (void) { scm_i_thread *thread = SCM_I_CURRENT_THREAD; scm_dynstack_unwind_fluid (&thread->dynstack, thread->dynamic_state); return SCM_UNSPECIFIED; } /* {Evaluator memoized expressions} */ scm_t_bits scm_tc16_memoized; #define MAKMEMO(n, args) \ (scm_cons (SCM_I_MAKINUM (n), args)) #define MAKMEMO_SEQ(head,tail) \ MAKMEMO (SCM_M_SEQ, scm_cons (head, tail)) #define MAKMEMO_IF(test, then, else_) \ MAKMEMO (SCM_M_IF, scm_cons (test, scm_cons (then, else_))) #define FIXED_ARITY(nreq) \ scm_list_1 (SCM_I_MAKINUM (nreq)) #define REST_ARITY(nreq, rest) \ scm_list_2 (SCM_I_MAKINUM (nreq), rest) #define FULL_ARITY(nreq, rest, nopt, kw, inits, alt) \ scm_list_n (SCM_I_MAKINUM (nreq), rest, SCM_I_MAKINUM (nopt), kw, inits, \ alt, SCM_UNDEFINED) #define MAKMEMO_LAMBDA(body, arity, meta) \ MAKMEMO (SCM_M_LAMBDA, \ scm_cons (body, scm_cons (meta, arity))) #define MAKMEMO_LET(inits, body) \ MAKMEMO (SCM_M_LET, scm_cons (inits, body)) #define MAKMEMO_QUOTE(exp) \ MAKMEMO (SCM_M_QUOTE, exp) #define MAKMEMO_DEFINE(var, val) \ MAKMEMO (SCM_M_DEFINE, scm_cons (var, val)) #define MAKMEMO_APPLY(proc, args)\ MAKMEMO (SCM_M_APPLY, scm_list_2 (proc, args)) #define MAKMEMO_CONT(proc) \ MAKMEMO (SCM_M_CONT, proc) #define MAKMEMO_CALL_WITH_VALUES(prod, cons) \ MAKMEMO (SCM_M_CALL_WITH_VALUES, scm_cons (prod, cons)) #define MAKMEMO_CALL(proc, nargs, args) \ MAKMEMO (SCM_M_CALL, scm_cons (proc, scm_cons (SCM_I_MAKINUM (nargs), args))) #define MAKMEMO_LEX_REF(pos) \ MAKMEMO (SCM_M_LEXICAL_REF, pos) #define MAKMEMO_LEX_SET(pos, val) \ MAKMEMO (SCM_M_LEXICAL_SET, scm_cons (pos, val)) #define MAKMEMO_TOP_REF(var) \ MAKMEMO (SCM_M_TOPLEVEL_REF, var) #define MAKMEMO_TOP_SET(var, val) \ MAKMEMO (SCM_M_TOPLEVEL_SET, scm_cons (var, val)) #define MAKMEMO_MOD_REF(mod, var, public) \ MAKMEMO (SCM_M_MODULE_REF, scm_cons (mod, scm_cons (var, public))) #define MAKMEMO_MOD_SET(val, mod, var, public) \ MAKMEMO (SCM_M_MODULE_SET, scm_cons (val, scm_cons (mod, scm_cons (var, public)))) #define MAKMEMO_CALL_WITH_PROMPT(tag, thunk, handler) \ MAKMEMO (SCM_M_CALL_WITH_PROMPT, scm_cons (tag, scm_cons (thunk, handler))) /* This table must agree with the list of M_ constants in memoize.h */ static const char *const memoized_tags[] = { "seq", "if", "lambda", "let", "quote", "define", "apply", "call/cc", "call-with-values", "call", "lexical-ref", "lexical-set!", "toplevel-ref", "toplevel-set!", "module-ref", "module-set!", "call-with-prompt", }; static int try_lookup_rib (SCM x, SCM rib) { int idx = 0; for (; idx < VECTOR_LENGTH (rib); idx++) if (scm_is_eq (x, VECTOR_REF (rib, idx))) return idx; /* bound */ return -1; } static int lookup_rib (SCM x, SCM rib) { int idx = try_lookup_rib (x, rib); if (idx < 0) abort (); return idx; } static SCM make_pos (int depth, int width) { return scm_cons (SCM_I_MAKINUM (depth), SCM_I_MAKINUM (width)); } static SCM lookup (SCM x, SCM env) { int d = 0; for (; scm_is_pair (env); env = CDR (env), d++) { int w = try_lookup_rib (x, CAR (env)); if (w < 0) continue; return make_pos (d, w); } abort (); } /* Abbreviate SCM_EXPANDED_REF. Copied because I'm not sure about symbol pasting */ #define REF(x,type,field) \ (scm_struct_ref (x, SCM_I_MAKINUM (SCM_EXPANDED_##type##_##field))) static SCM list_of_guile = SCM_BOOL_F; static SCM memoize (SCM exp, SCM env); static SCM memoize_exps (SCM exps, SCM env) { SCM ret; for (ret = SCM_EOL; scm_is_pair (exps); exps = CDR (exps)) ret = scm_cons (memoize (CAR (exps), env), ret); return scm_reverse_x (ret, SCM_UNDEFINED); } static SCM memoize (SCM exp, SCM env) { if (!SCM_EXPANDED_P (exp)) abort (); switch (SCM_EXPANDED_TYPE (exp)) { case SCM_EXPANDED_VOID: return MAKMEMO_QUOTE (SCM_UNSPECIFIED); case SCM_EXPANDED_CONST: return MAKMEMO_QUOTE (REF (exp, CONST, EXP)); case SCM_EXPANDED_PRIMITIVE_REF: if (scm_is_eq (scm_current_module (), scm_the_root_module ())) return MAKMEMO_TOP_REF (REF (exp, PRIMITIVE_REF, NAME)); else return MAKMEMO_MOD_REF (list_of_guile, REF (exp, PRIMITIVE_REF, NAME), SCM_BOOL_F); case SCM_EXPANDED_LEXICAL_REF: return MAKMEMO_LEX_REF (lookup (REF (exp, LEXICAL_REF, GENSYM), env)); case SCM_EXPANDED_LEXICAL_SET: return MAKMEMO_LEX_SET (lookup (REF (exp, LEXICAL_SET, GENSYM), env), memoize (REF (exp, LEXICAL_SET, EXP), env)); case SCM_EXPANDED_MODULE_REF: return MAKMEMO_MOD_REF (REF (exp, MODULE_REF, MOD), REF (exp, MODULE_REF, NAME), REF (exp, MODULE_REF, PUBLIC)); case SCM_EXPANDED_MODULE_SET: return MAKMEMO_MOD_SET (memoize (REF (exp, MODULE_SET, EXP), env), REF (exp, MODULE_SET, MOD), REF (exp, MODULE_SET, NAME), REF (exp, MODULE_SET, PUBLIC)); case SCM_EXPANDED_TOPLEVEL_REF: return MAKMEMO_TOP_REF (REF (exp, TOPLEVEL_REF, NAME)); case SCM_EXPANDED_TOPLEVEL_SET: return MAKMEMO_TOP_SET (REF (exp, TOPLEVEL_SET, NAME), memoize (REF (exp, TOPLEVEL_SET, EXP), env)); case SCM_EXPANDED_TOPLEVEL_DEFINE: return MAKMEMO_DEFINE (REF (exp, TOPLEVEL_DEFINE, NAME), memoize (REF (exp, TOPLEVEL_DEFINE, EXP), env)); case SCM_EXPANDED_CONDITIONAL: return MAKMEMO_IF (memoize (REF (exp, CONDITIONAL, TEST), env), memoize (REF (exp, CONDITIONAL, CONSEQUENT), env), memoize (REF (exp, CONDITIONAL, ALTERNATE), env)); case SCM_EXPANDED_CALL: { SCM proc, args; proc = REF (exp, CALL, PROC); args = memoize_exps (REF (exp, CALL, ARGS), env); return MAKMEMO_CALL (memoize (proc, env), scm_ilength (args), args); } case SCM_EXPANDED_PRIMCALL: { SCM name, args; int nargs; name = REF (exp, PRIMCALL, NAME); args = memoize_exps (REF (exp, PRIMCALL, ARGS), env); nargs = scm_ilength (args); if (nargs == 3 && scm_is_eq (name, scm_from_latin1_symbol ("call-with-prompt"))) return MAKMEMO_CALL_WITH_PROMPT (CAR (args), CADR (args), CADDR (args)); else if (nargs == 2 && scm_is_eq (name, scm_from_latin1_symbol ("apply"))) return MAKMEMO_APPLY (CAR (args), CADR (args)); else if (nargs == 1 && scm_is_eq (name, scm_from_latin1_symbol ("call-with-current-continuation"))) return MAKMEMO_CONT (CAR (args)); else if (nargs == 2 && scm_is_eq (name, scm_from_latin1_symbol ("call-with-values"))) return MAKMEMO_CALL_WITH_VALUES (CAR (args), CADR (args)); else if (nargs == 2 && scm_is_eq (name, scm_from_latin1_symbol ("wind"))) return MAKMEMO_CALL (MAKMEMO_QUOTE (wind), 2, args); else if (nargs == 0 && scm_is_eq (name, scm_from_latin1_symbol ("unwind"))) return MAKMEMO_CALL (MAKMEMO_QUOTE (unwind), 0, SCM_EOL); else if (nargs == 2 && scm_is_eq (name, scm_from_latin1_symbol ("push-fluid"))) return MAKMEMO_CALL (MAKMEMO_QUOTE (push_fluid), 2, args); else if (nargs == 0 && scm_is_eq (name, scm_from_latin1_symbol ("pop-fluid"))) return MAKMEMO_CALL (MAKMEMO_QUOTE (pop_fluid), 0, SCM_EOL); else if (scm_is_eq (scm_current_module (), scm_the_root_module ())) return MAKMEMO_CALL (MAKMEMO_TOP_REF (name), nargs, args); else return MAKMEMO_CALL (MAKMEMO_MOD_REF (list_of_guile, name, SCM_BOOL_F), nargs, args); } case SCM_EXPANDED_SEQ: return MAKMEMO_SEQ (memoize (REF (exp, SEQ, HEAD), env), memoize (REF (exp, SEQ, TAIL), env)); case SCM_EXPANDED_LAMBDA: /* The body will be a lambda-case or #f. */ { SCM meta, body, proc; meta = REF (exp, LAMBDA, META); body = REF (exp, LAMBDA, BODY); if (scm_is_false (body)) /* Give a body to case-lambda with no clauses. */ proc = MAKMEMO_LAMBDA (MAKMEMO_CALL (MAKMEMO_MOD_REF (list_of_guile, scm_from_latin1_symbol ("throw"), SCM_BOOL_F), 5, scm_list_5 (MAKMEMO_QUOTE (scm_args_number_key), MAKMEMO_QUOTE (SCM_BOOL_F), MAKMEMO_QUOTE (scm_from_latin1_string ("Wrong number of arguments")), MAKMEMO_QUOTE (SCM_EOL), MAKMEMO_QUOTE (SCM_BOOL_F))), FIXED_ARITY (0), meta); else { proc = memoize (body, env); SCM_SETCAR (SCM_CDR (SCM_MEMOIZED_ARGS (proc)), meta); } return proc; } case SCM_EXPANDED_LAMBDA_CASE: { SCM req, rest, opt, kw, inits, vars, body, alt; SCM walk, minits, arity, rib, new_env; int nreq, nopt; req = REF (exp, LAMBDA_CASE, REQ); rest = scm_not (scm_not (REF (exp, LAMBDA_CASE, REST))); opt = REF (exp, LAMBDA_CASE, OPT); kw = REF (exp, LAMBDA_CASE, KW); inits = REF (exp, LAMBDA_CASE, INITS); vars = REF (exp, LAMBDA_CASE, GENSYMS); body = REF (exp, LAMBDA_CASE, BODY); alt = REF (exp, LAMBDA_CASE, ALTERNATE); nreq = scm_ilength (req); nopt = scm_is_pair (opt) ? scm_ilength (opt) : 0; /* The vars are the gensyms, according to the divine plan. But we need to memoize the inits within their appropriate environment, complicating things. */ rib = scm_vector (vars); new_env = scm_cons (rib, env); minits = SCM_EOL; for (walk = inits; scm_is_pair (walk); walk = CDR (walk)) minits = scm_cons (memoize (CAR (walk), new_env), minits); minits = scm_reverse_x (minits, SCM_UNDEFINED); if (scm_is_true (kw)) { /* (aok? (kw name sym) ...) -> (aok? (kw . index) ...) */ SCM aok = CAR (kw), indices = SCM_EOL; for (kw = CDR (kw); scm_is_pair (kw); kw = CDR (kw)) { SCM k; int idx; k = CAR (CAR (kw)); idx = lookup_rib (CADDR (CAR (kw)), rib); indices = scm_acons (k, SCM_I_MAKINUM (idx), indices); } kw = scm_cons (aok, scm_reverse_x (indices, SCM_UNDEFINED)); } if (scm_is_false (alt) && scm_is_false (kw) && scm_is_false (opt)) { if (scm_is_false (rest)) arity = FIXED_ARITY (nreq); else arity = REST_ARITY (nreq, SCM_BOOL_T); } else if (scm_is_true (alt)) arity = FULL_ARITY (nreq, rest, nopt, kw, minits, SCM_MEMOIZED_ARGS (memoize (alt, env))); else arity = FULL_ARITY (nreq, rest, nopt, kw, minits, SCM_BOOL_F); return MAKMEMO_LAMBDA (memoize (body, new_env), arity, SCM_BOOL_F /* meta, filled in later */); } case SCM_EXPANDED_LET: { SCM vars, exps, body, varsv, inits, new_env; int i; vars = REF (exp, LET, GENSYMS); exps = REF (exp, LET, VALS); body = REF (exp, LET, BODY); varsv = scm_vector (vars); inits = scm_c_make_vector (VECTOR_LENGTH (varsv), SCM_BOOL_F); new_env = scm_cons (varsv, env); for (i = 0; scm_is_pair (exps); exps = CDR (exps), i++) VECTOR_SET (inits, i, memoize (CAR (exps), env)); return MAKMEMO_LET (inits, memoize (body, new_env)); } case SCM_EXPANDED_LETREC: { SCM vars, varsv, exps, expsv, body, undefs, new_env; int i, nvars, in_order_p; vars = REF (exp, LETREC, GENSYMS); exps = REF (exp, LETREC, VALS); body = REF (exp, LETREC, BODY); in_order_p = scm_is_true (REF (exp, LETREC, IN_ORDER_P)); varsv = scm_vector (vars); nvars = VECTOR_LENGTH (varsv); expsv = scm_vector (exps); undefs = scm_c_make_vector (nvars, MAKMEMO_QUOTE (SCM_UNDEFINED)); new_env = scm_cons (varsv, env); if (in_order_p) { SCM body_exps = memoize (body, new_env); for (i = nvars - 1; i >= 0; i--) { SCM init = memoize (VECTOR_REF (expsv, i), new_env); body_exps = MAKMEMO_SEQ (MAKMEMO_LEX_SET (make_pos (0, i), init), body_exps); } return MAKMEMO_LET (undefs, body_exps); } else { SCM sets = SCM_BOOL_F, inits = scm_c_make_vector (nvars, SCM_BOOL_F); for (i = nvars - 1; i >= 0; i--) { SCM init, set; init = memoize (VECTOR_REF (expsv, i), new_env); VECTOR_SET (inits, i, init); set = MAKMEMO_LEX_SET (make_pos (1, i), MAKMEMO_LEX_REF (make_pos (0, i))); if (scm_is_false (sets)) sets = set; else sets = MAKMEMO_SEQ (set, sets); } if (scm_is_false (sets)) return memoize (body, env); return MAKMEMO_LET (undefs, MAKMEMO_SEQ (MAKMEMO_LET (inits, sets), memoize (body, new_env))); } } default: abort (); } } SCM_DEFINE (scm_memoize_expression, "memoize-expression", 1, 0, 0, (SCM exp), "Memoize the expression @var{exp}.") #define FUNC_NAME s_scm_memoize_expression { SCM_ASSERT_TYPE (SCM_EXPANDED_P (exp), exp, 1, FUNC_NAME, "expanded"); return memoize (exp, scm_current_module ()); } #undef FUNC_NAME SCM_SYMBOL (sym_placeholder, "_"); static SCM unmemoize (SCM expr); static SCM unmemoize_exprs (SCM exprs) { SCM ret, tail; if (scm_is_null (exprs)) return SCM_EOL; ret = scm_list_1 (unmemoize (CAR (exprs))); tail = ret; for (exprs = CDR (exprs); !scm_is_null (exprs); exprs = CDR (exprs)) { SCM_SETCDR (tail, scm_list_1 (unmemoize (CAR (exprs)))); tail = CDR (tail); } return ret; } static SCM unmemoize_bindings (SCM inits) { SCM ret = SCM_EOL; int n = scm_c_vector_length (inits); while (n--) ret = scm_cons (unmemoize (scm_c_vector_ref (inits, n)), ret); return ret; } static SCM unmemoize_lexical (SCM n) { char buf[32]; buf[31] = 0; snprintf (buf, 31, "<%u,%u>", scm_to_uint32 (CAR (n)), scm_to_uint32 (CDR (n))); return scm_from_utf8_symbol (buf); } static SCM unmemoize (const SCM expr) { SCM args; args = SCM_MEMOIZED_ARGS (expr); switch (SCM_MEMOIZED_TAG (expr)) { case SCM_M_APPLY: return scm_cons (scm_from_latin1_symbol ("apply"), unmemoize_exprs (args)); case SCM_M_SEQ: return scm_list_3 (scm_sym_begin, unmemoize (CAR (args)), unmemoize (CDR (args))); case SCM_M_CALL: return scm_cons (unmemoize (CAR (args)), unmemoize_exprs (CDDR (args))); case SCM_M_CONT: return scm_list_2 (scm_from_latin1_symbol ("call-with-current_continuation"), unmemoize (args)); case SCM_M_CALL_WITH_VALUES: return scm_list_3 (scm_from_latin1_symbol ("call-with-values"), unmemoize (CAR (args)), unmemoize (CDR (args))); case SCM_M_DEFINE: return scm_list_3 (scm_sym_define, CAR (args), unmemoize (CDR (args))); case SCM_M_IF: return scm_list_4 (scm_sym_if, unmemoize (scm_car (args)), unmemoize (scm_cadr (args)), unmemoize (scm_cddr (args))); case SCM_M_LAMBDA: { SCM body = CAR (args), spec = CDDR (args); if (scm_is_null (CDR (spec))) return scm_list_3 (scm_sym_lambda, scm_make_list (CAR (spec), sym_placeholder), unmemoize (CAR (args))); else if (scm_is_null (SCM_CDDR (spec))) { SCM formals = scm_make_list (CAR (spec), sym_placeholder); return scm_list_3 (scm_sym_lambda, scm_is_true (CADR (spec)) ? scm_cons_star (sym_placeholder, formals) : formals, unmemoize (CAR (args))); } else { SCM alt, tail; alt = CADDR (CDDDR (spec)); if (scm_is_true (alt)) tail = CDR (unmemoize (alt)); else tail = SCM_EOL; return scm_cons (sym_case_lambda_star, scm_cons (scm_list_2 (scm_list_5 (CAR (spec), CADR (spec), CADDR (spec), CADDDR (spec), unmemoize_exprs (CADR (CDDDR (spec)))), unmemoize (body)), tail)); } } case SCM_M_LET: return scm_list_3 (scm_sym_let, unmemoize_bindings (CAR (args)), unmemoize (CDR (args))); case SCM_M_QUOTE: return scm_list_2 (scm_sym_quote, args); case SCM_M_LEXICAL_REF: return unmemoize_lexical (args); case SCM_M_LEXICAL_SET: return scm_list_3 (scm_sym_set_x, unmemoize_lexical (CAR (args)), unmemoize (CDR (args))); case SCM_M_TOPLEVEL_REF: return args; case SCM_M_TOPLEVEL_SET: return scm_list_3 (scm_sym_set_x, CAR (args), unmemoize (CDR (args))); case SCM_M_MODULE_REF: return SCM_VARIABLEP (args) ? args : scm_list_3 (scm_is_true (CDDR (args)) ? scm_sym_at : scm_sym_atat, scm_i_finite_list_copy (CAR (args)), CADR (args)); case SCM_M_MODULE_SET: return scm_list_3 (scm_sym_set_x, SCM_VARIABLEP (CDR (args)) ? CDR (args) : scm_list_3 (scm_is_true (CDDDR (args)) ? scm_sym_at : scm_sym_atat, scm_i_finite_list_copy (CADR (args)), CADDR (args)), unmemoize (CAR (args))); case SCM_M_CALL_WITH_PROMPT: return scm_list_4 (scm_from_latin1_symbol ("call-with-prompt"), unmemoize (CAR (args)), unmemoize (CADR (args)), unmemoize (CDDR (args))); default: abort (); } } SCM_DEFINE (scm_unmemoize_expression, "unmemoize-expression", 1, 0, 0, (SCM m), "Unmemoize the memoized expression @var{m}.") #define FUNC_NAME s_scm_unmemoize_expression { return unmemoize (m); } #undef FUNC_NAME SCM_DEFINE (scm_memoized_typecode, "memoized-typecode", 1, 0, 0, (SCM sym), "Return the memoized typecode corresponding to the symbol @var{sym}.") #define FUNC_NAME s_scm_memoized_typecode { int i; SCM_VALIDATE_SYMBOL (1, sym); for (i = 0; i < sizeof(memoized_tags)/sizeof(const char*); i++) if (strcmp (scm_i_symbol_chars (sym), memoized_tags[i]) == 0) return scm_from_int32 (i); return SCM_BOOL_F; } #undef FUNC_NAME SCM_SYMBOL (scm_unbound_variable_key, "unbound-variable"); static void error_unbound_variable (SCM symbol) SCM_NORETURN; static void error_unbound_variable (SCM symbol) { scm_error (scm_unbound_variable_key, NULL, "Unbound variable: ~S", scm_list_1 (symbol), SCM_BOOL_F); } SCM_DEFINE (scm_memoize_variable_access_x, "memoize-variable-access!", 2, 0, 0, (SCM m, SCM mod), "Look up and cache the variable that @var{m} will access, returning the variable.") #define FUNC_NAME s_scm_memoize_variable_access_x { SCM mx = SCM_MEMOIZED_ARGS (m); switch (SCM_MEMOIZED_TAG (m)) { case SCM_M_TOPLEVEL_REF: if (SCM_VARIABLEP (mx)) return mx; else { SCM var = scm_module_variable (mod, mx); if (scm_is_false (var) || scm_is_false (scm_variable_bound_p (var))) error_unbound_variable (mx); SCM_SETCDR (m, var); return var; } case SCM_M_TOPLEVEL_SET: { SCM var = CAR (mx); if (SCM_VARIABLEP (var)) return var; else { var = scm_module_variable (mod, var); if (scm_is_false (var)) error_unbound_variable (CAR (mx)); SCM_SETCAR (mx, var); return var; } } case SCM_M_MODULE_REF: if (SCM_VARIABLEP (mx)) return mx; else { SCM var; mod = scm_resolve_module (CAR (mx)); if (scm_is_true (CDDR (mx))) mod = scm_module_public_interface (mod); var = scm_module_lookup (mod, CADR (mx)); if (scm_is_false (scm_variable_bound_p (var))) error_unbound_variable (CADR (mx)); SCM_SETCDR (m, var); return var; } case SCM_M_MODULE_SET: /* FIXME: not quite threadsafe */ if (SCM_VARIABLEP (CDR (mx))) return CDR (mx); else { SCM var; mod = scm_resolve_module (CADR (mx)); if (scm_is_true (CDDDR (mx))) mod = scm_module_public_interface (mod); var = scm_module_lookup (mod, CADDR (mx)); SCM_SETCDR (mx, var); return var; } default: scm_wrong_type_arg (FUNC_NAME, 1, m); return SCM_BOOL_F; } } #undef FUNC_NAME void scm_init_memoize () { #include "libguile/memoize.x" wind = scm_c_make_gsubr ("wind", 2, 0, 0, do_wind); unwind = scm_c_make_gsubr ("unwind", 0, 0, 0, do_unwind); push_fluid = scm_c_make_gsubr ("push-fluid", 2, 0, 0, do_push_fluid); pop_fluid = scm_c_make_gsubr ("pop-fluid", 0, 0, 0, do_pop_fluid); list_of_guile = scm_list_1 (scm_from_latin1_symbol ("guile")); } /* Local Variables: c-file-style: "gnu" End: */