Use new pushback token priming for single regex parse.

* parser.h (enum prime_parser): New enum.
(prime_parser, prime_scanner, parse): Declarations updated with new
argument.

* parser.c (prime_parser): New argument of enum prime_parser type
Select appropriate secret token for regex and Lisp case.  Pass prime
selector down to prime_scanner.
(regex_parse): Do not prepend secret escape to string.  Do not use
parse_once function; instead do the parser init and cleanup here and
use the parse function.
(lisp_parse): Pass new argument to parse, configuring the parser to be
primed for Lisp parsing.

* parser.l (grammar): Rule producing SECRET_ESCAPE_R removed.
(prime_scanner): New argument. Pop the scanner state down to INITIAL.
Then unconditionally switch to appopriate state based on priming
configuration.

* parser.y (parse): New argument for priming selection, passed down to
prime parser.

1 files changed, 5 insertions, 3 deletions

diff --git a/parser.h b/parser.h
index bedebfbe..fe8e4413 100644
--- a/parser.h
+++ b/parser.h
@@ -56,6 +56,8 @@ struct parser {
 };
 #endif
 
+enum prime_parser { prime_lisp, prime_regex };
+
 extern const wchar_t *spec_file;
 extern val form_to_ln_hash;
 extern val parser_s;
@@ -76,10 +78,10 @@ void yyset_extra(parser_t *, yyscan_t);
 void yyset_hold_char(yyscan_t, int);
 void parser_l_init(void);
 void open_txr_file(val spec_file, val *txr_lisp_p, val *name, val *stream);
-void prime_parser(parser_t *, val name);
-void prime_scanner(scanner_t *);
+void prime_parser(parser_t *, val name, enum prime_parser);
+void prime_scanner(scanner_t *, enum prime_parser);
 int parse_once(val stream, val name, parser_t *parser);
-int parse(parser_t *parser, val name);
+int parse(parser_t *parser, val name, enum prime_parser);
 val source_loc(val form);
 val source_loc_str(val form, val alt);
 val rlset(val form, val info);