diff options
| -rw-r--r-- | ChangeLog | 16 | ||||
| -rw-r--r-- | eval.c | 119 |
2 files changed, 61 insertions, 74 deletions
@@ -1,5 +1,21 @@ 2014-02-23 Kaz Kylheku <kaz@kylheku.com> + * eval.c (bindings_helper): This must now bind dynamic values + rather than just assign to them. Got rid of the superfluous variable + saving array. Fixed the problem in recognizing the special_s symbol (it + is bindable). + (op_with_saved_vars): This simplifies, since it no longer needs + to save individual variables in an array, only to set up and + tear down a new dynamic environment frame. + (expand_vars): No longer returns two values with a cons. + Takes a form argument for error reporting and a pointer to a boolean + just to report whether there are special vars without listing them. + (expand_save_specials): The with-saved-specials form doesn't need + a var list any more, so the expander is updated not to stick them in. + (expand): Update calls to expand_vars to new interface. + +2014-02-23 Kaz Kylheku <kaz@kylheku.com> + * stream.c (get_string_from_stream): Bugfix: do not abort if stream is not a string stream, but throw a proper error exception. @@ -950,9 +950,8 @@ static val bindings_helper(val vars, val env, val sequential, { val iter; list_collect_decl (new_bindings, ptail); + list_collect_decl (new_dyn_bindings, ptail_d); val nenv = if3(sequential, make_env(nil, nil, env), env); - val spec_val[32], *spec_loc[32]; - int speci = 0; for (iter = vars; iter; iter = cdr(iter)) { val item = car(iter); @@ -965,35 +964,28 @@ static val bindings_helper(val vars, val env, val sequential, var = item; } - if (!bindable(var)) { + if (var == special_s) { val special = car(item); - val *loc = lookup_var_l(nil, special); - if (var != special_s) - eval_error(ctx_form, lit("~s: ~s is not a bindable symbol"), - car(ctx_form), var, nao); - if (!loc) - eval_error(ctx_form, lit("~s: cannot rebind variable ~s: not found"), - car(ctx_form), special, nao); - if (sequential) { - *loc = value; - } else if (speci < 32) { - spec_val[speci] = value; - spec_loc[speci++] = loc; - } else { - eval_error(ctx_form, lit("~s: too many special variables rebound"), - car(ctx_form), nao); - } + ptail_d = list_collect(ptail_d, cons(special, value)); + + if (sequential) + env_replace_vbind(dyn_env, new_dyn_bindings); + if (include_specials) ptail = list_collect (ptail, cons(special_s, var)); - } else { + } else if (bindable(var)) { ptail = list_collect (ptail, cons(var, value)); if (sequential) env_replace_vbind(nenv, new_bindings); + } else { + eval_error(ctx_form, lit("~s: ~s is not a bindable symbol"), + car(ctx_form), var, nao); } } - while (speci-- > 0) - *spec_loc[speci] = spec_val[speci]; + + if (new_dyn_bindings) + env_replace_vbind(dyn_env, new_dyn_bindings); return new_bindings; } @@ -1823,34 +1815,10 @@ static val op_quasi_lit(val form, val env) static val op_with_saved_vars(val form, val env) { - val vars = (pop(&form), pop(&form)); - val prot_form = pop(&form); - val result = nil; - val var_save[32], *var_loc[32]; - int n; - - uw_simple_catch_begin; - - for (n = 0; n < 32 && vars; n++, vars = cdr(vars)) { - val sym = car(vars); - val *loc = lookup_var_l(nil, sym); - if (!loc) { - eval_error(form, lit("~s: cannot save value of " - "nonexistent var ~a"), car(form), sym, nao); - } - var_loc[n] = loc; - var_save[n] = *loc; - } - - result = eval(prot_form, env, prot_form); - - uw_unwind { - while (n-- > 0) - *var_loc[n] = var_save[n]; - } - - uw_catch_end; - + val prot_form = second(form); + val saved_de = set_dyn_env(make_env(nil, nil, dyn_env)); + val result = eval(prot_form, env, prot_form); + set_dyn_env(saved_de); return result; } @@ -1997,42 +1965,43 @@ static val expand_qquote(val qquoted_form, val menv) abort(); } -static val expand_vars(val vars, val specials, val menv) +static val expand_vars(val vars, val menv, val form, val *spec_p) { val sym; - if (atom(vars)) { + if (nilp(vars)) { + return nil; + } else if (atom(vars)) { + eval_error(form, lit("~a is an invalid variable binding syntax"), + vars, nao); return vars; } else if (special_p(sym = car(vars))) { val rest_vars = rest(vars); - cons_bind (rest_vars_ex, new_specials, - rlcp(expand_vars(rest_vars, specials, menv), rest_vars)); - val ret_specials = cons(sym, new_specials); + val rest_vars_ex = rlcp(expand_vars(rest_vars, menv, form, spec_p), + rest_vars); val var_ex = cons(special_s, cons(nil, cons(sym, nil))); - return cons(rlcp(cons(var_ex, rest_vars_ex), vars), ret_specials); + return rlcp(cons(var_ex, rest_vars_ex), vars); } else if (symbolp(sym)) { val rest_vars = rest(vars); - cons_bind (rest_vars_ex, new_specials, - expand_vars(rest_vars, specials, menv)); + val rest_vars_ex = expand_vars(rest_vars, menv, form, spec_p); if (rest_vars == rest_vars_ex) - return cons(vars, new_specials); - return cons(rlcp(cons(sym, rest_vars_ex), vars), new_specials); + return vars; + return rlcp(cons(sym, rest_vars_ex), vars); } else { cons_bind (var, init, sym); val rest_vars = rest(vars); val init_ex = rlcp(expand_forms(init, menv), init); - cons_bind (rest_vars_ex, new_specials, - rlcp(expand_vars(rest_vars, specials, menv), rest_vars)); + val rest_vars_ex = rlcp(expand_vars(rest_vars, menv, form, spec_p), + rest_vars); if (special_p(var)) { - val ret_specials = cons(var, new_specials); val var_ex = cons(special_s, cons(car(init_ex), cons(var, nil))); - return cons(rlcp(cons(var_ex, rest_vars_ex), vars), ret_specials); + *spec_p = t; + return rlcp(cons(var_ex, rest_vars_ex), vars); } else { if (init == init_ex && rest_vars == rest_vars_ex) - return cons(vars, new_specials); - return cons(rlcp(cons(cons(var, init_ex), rest_vars_ex), vars), - new_specials); + return vars; + return rlcp(cons(cons(var, init_ex), rest_vars_ex), vars); } } } @@ -2246,7 +2215,7 @@ static val expand_save_specials(val form, val specials) { if (!specials) return form; - return rlcp(cons(with_saved_vars_s, cons(specials, cons(form, nil))), form); + return rlcp(cons(with_saved_vars_s, cons(form, nil)), form); } val expand(val form, val menv) @@ -2269,12 +2238,13 @@ tail: val body = rest(rest(form)); val vars = second(form); val body_ex = expand_forms(body, menv); - cons_bind (vars_ex, specials, expand_vars(vars, nil, menv)); - if (body == body_ex && vars == vars_ex && !specials) { + val specials_p = nil; + val vars_ex = expand_vars(vars, menv, form, &specials_p); + if (body == body_ex && vars == vars_ex && !specials_p) { return form; } else { val basic_form = rlcp(cons(sym, cons(vars_ex, body_ex)), form); - return expand_save_specials(basic_form, specials); + return expand_save_specials(basic_form, specials_p); } } else if (sym == block_s || sym == return_from_s) { val name = second(form); @@ -2371,20 +2341,21 @@ tail: val cond = third(form); val incs = fourth(form); val forms = rest(rest(rest(rest(form)))); - cons_bind (vars_ex, specials, expand_vars(vars, nil, menv)); + val specials_p = nil; + val vars_ex = expand_vars(vars, menv, form, &specials_p); val cond_ex = expand_forms(cond, menv); val incs_ex = expand_forms(incs, menv); val forms_ex = expand_forms(forms, menv); if (vars == vars_ex && cond == cond_ex && - incs == incs_ex && forms == forms_ex && !specials) { + incs == incs_ex && forms == forms_ex && !specials_p) { return form; } else { val basic_form = rlcp(cons(sym, cons(vars_ex, cons(cond_ex, cons(incs_ex, forms_ex)))), form); - return expand_save_specials(basic_form, specials); + return expand_save_specials(basic_form, specials_p); } } else if (sym == dohash_s) { val spec = second(form); |