parser: always use stream-associated parser for parse_once.

This refactoring is needed for fixing the off-by-one
line number bug when the hash bang line is processed.

* eval.c (load): Don't define parser locally; ensure there is
one in the stream and use it.

* match.c (v_load): Likewise.

* parser.c (get_parser_impl): Renamed to parser_get_impl and
changed from internal to external linkage.
(ensure_parser): Changed to external linkage.
(lisp_parser_impl, read_file_common): Follow rename of
get_parser_impl.

* parser.h (parse_once): Declaration updated.
(parser_get_impl, ensure_parser): Declared.

* parser.y (parse_once): Take self parameter; drop parser
parameter. Ensure a parser to the stream, rather than
declaring one locally. Don't clean up the parser when
done, just let the stream clean it up.

* txr.c (parse_once_noerr): Parser argument is dropped and
not passed to parse_once. Program name is passed as self
argument to parse_once.
(txr_main): When parsing the TXR pattern query, don't define a
parser locally; ensure there is one in the stream and use it,
like in load and v_load.

1 files changed, 5 insertions, 4 deletions

diff --git a/eval.c b/eval.c
index a91d7bc8..ee9ac973 100644
--- a/eval.c
+++ b/eval.c
@@ -4364,21 +4364,22 @@ val load(val target)
     }
   } else {
     int gc = gc_state(0);
-    parser_t parser;
-    parse_once(stream, name, &parser);
+    val parser_obj = ensure_parser(stream);
+    parser_t *parser = parser_get_impl(self, parser_obj);
+    parse_once(self, stream, name);
     gc_state(gc);
 
     close_stream(stream, nil);
 
     uw_release_deferred_warnings();
 
-    if (parser.errors)
+    if (parser->errors)
       uw_throwf(query_error_s, lit("~a: parser errors in ~a"),
                 self, path, nao);
     {
       val match_ctx = uw_get_match_context();
       val bindings = cdr(match_ctx);
-      val result = extract(parser.syntax_tree, nil, bindings);
+      val result = extract(parser->syntax_tree, nil, bindings);
       cons_bind (new_bindings, success, result);
       if (success)
         uw_set_match_context(cons(car(match_ctx), new_bindings));