read_from_chars module/op confusion, re issue #909

Author: infradig

library/builtins.pl

@@ -17,6 +17,11 @@
 
 :- help(predicate_property(+callable,+term), [iso(true)]).
 
+read_from_chars(Cs, T) :-
+    read_term_from_chars(Cs, T, []).
+
+:- help(read_from_chars(+chars,?term), [iso(false)]).
+
 predicate_property(P, A) :-
 	nonvar(P), atom(A), !,
 	must_be(P, callable, predicate_property/2, _),

library/charsio.pl

@@ -2,8 +2,7 @@
 	char_type/2,
 	get_line_to_chars/3,
 	get_single_char/1,
-	get_n_chars/3,
-	read_from_chars/2
+	get_n_chars/3
 	]).
 
 get_single_char(C) :-
@@ -22,11 +21,6 @@
 		Cs0 = Cs
 	).
 
-read_from_chars(Cs, T) :-
-    read_term_from_chars(Cs, T, []).
-
-:- help(read_from_chars(+chars,?term), [iso(false)]).
-
 fabricate_var_name(VarType, VarName, N) :-
     char_code('A', AC),
     LN is N mod 26 + AC,

src/bif_streams.c

@@ -4186,20 +4186,13 @@ static bool bif_sys_read_term_from_chars_4(query *q)
 		return throw_error(q, p_chars, p_chars_ctx, "type_error", "character");
 	}
 
-	str->p = parser_create(q->st.m);
-	str->p->flags = q->st.m->flags;
-	str->p->fp = str->fp;
-	parser_reset(str->p);
-	str->p->srcptr = src;
-
 	if (!src || !*src) {
-		parser_destroy(str->p);
 		cell tmp;
 		make_atom(&tmp, g_eof_s);
 		return unify(q, p_term, p_term_ctx, &tmp, q->st.cur_ctx);
 	}
 
-	bool ok = do_read_term(q, str, p_term, p_term_ctx, p_opts, p_opts_ctx, NULL);
+	bool ok = do_read_term(q, str, p_term, p_term_ctx, p_opts, p_opts_ctx, src);
 
 	if (ok != true) {
 		if (!is_string(p_chars))
@@ -4232,8 +4225,6 @@ static bool bif_sys_read_term_from_chars_4(query *q)
 		make_atom(&tmp, g_nil_s);
 	}
 
-	parser_destroy(str->p);
-
 	if (!is_string(p_chars))
 		free(src);
 
@@ -4281,21 +4272,6 @@ static bool bif_read_term_from_chars_3(query *q)
 		return throw_error(q, p_chars, p_chars_ctx, "type_error", "character");
 	}
 
-	str->p = parser_create(q->st.m);
-	str->p->flags = q->st.m->flags;
-	str->p->fp = str->fp;
-	parser_reset(str->p);
-	char *save_src = src;
-	str->p->srcptr = src;
-
-	if (!src || !*src) {
-		parser_destroy(str->p);
-		free(save_src);
-		cell tmp;
-		make_atom(&tmp, g_eof_s);
-		return unify(q, p_term, p_term_ctx, &tmp, q->st.cur_ctx);
-	}
-
 	const char *end_ptr = src + strlen(src) - 1;
 
 	while (isspace(*end_ptr) && (end_ptr != src))
@@ -4304,14 +4280,8 @@ static bool bif_read_term_from_chars_3(query *q)
 	if (src[strlen(src)-1] != '.')
 		strcat(src, ".");
 
-	bool ok = do_read_term(q, str, p_term, p_term_ctx, p_opts, p_opts_ctx, NULL);
-	parser_reset(str->p);
-	parser_destroy(str->p);
-	free(save_src);
-
-	if (ok != true)
-		return false;
-
+	bool ok = do_read_term(q, str, p_term, p_term_ctx, p_opts, p_opts_ctx, src);
+	free(src);
 	return ok;
 }
 
@@ -4349,7 +4319,6 @@ static bool bif_read_term_from_atom_3(query *q)
 		strcat(src, ".");
 
 	bool ok = do_read_term(q, str, p_term, p_term_ctx, p_opts, p_opts_ctx, src);
-	parser_destroy(str->p);
 	free(src);
 	return ok;
 }

tests/issues/test905.expected

@@ -1 +1 @@
-   Warning: Initialization goal exception: error(existence_error(procedure,read_from_chars/2),read_from_chars/2).
+   Warning: Initialization goal exception: error(syntax_error(read_term),read_term_from_chars/3).