Semantics change. If a variable is followed by a mixture

of text and regular expressions, that whole mixture is
considered to follow the variable and used for matching.

The earlier semantics change whereby a single unescaped
space denotes the regular expression / +/ broke the
simple case   @a word.   It caused the @a to be followed
not by the text " word"  but by just the regular expression
element.

With this change @a word means that a is followed by
the regex / +/ and "word".

* match.c (text_s): New symbol variable.
(h_text): New function.
(syms_init): Initialize new symbol variable.
(dir_tables_init): Hook h_text into horizontal directives table.

* match.h (text_s): Declared.

* parser.y (text, texts): New nonterminals.
(elem): TEXT, SPACE and regex are now handled under texts
grammar production. All texts are run together and produce
an item which looks like (text items ...).

* txr.1, RELNOTES: Updated.

* txr.c (remove_hash_bang_line): Updated to find #! buried
in (text ...) syntax.

1 files changed, 18 insertions, 1 deletions

diff --git a/match.c b/match.c
index 52f79624..9f49657d 100644
--- a/match.c
+++ b/match.c
@@ -54,7 +54,7 @@ int opt_arraydims = 1;
 val decline_k, next_spec_k, repeat_spec_k;
 val mingap_k, maxgap_k, gap_k, mintimes_k, maxtimes_k, times_k;
 val lines_k, chars_k;
-val choose_s, gather_s;
+val text_s, choose_s, gather_s;
 val longest_k, shortest_k, greedy_k;
 val vars_k, resolve_k;
 val append_k, into_k, var_k, list_k, string_k, env_k;
@@ -400,6 +400,21 @@ typedef val (*h_match_func)(match_line_ctx c, match_line_ctx *cout);
   val elem_var = first(specline);                       \
   val directive_var = first(elem_var)
 
+static val h_text(match_line_ctx c, match_line_ctx *cout)
+{
+  val elem = first(c.specline);
+  val texts = rest(elem);
+  val new_pos = cdr(match_line(ml_specline(c, texts)));
+
+  if (new_pos) {
+    c.pos = new_pos;
+    *cout = c;
+    return next_spec_k;
+  }
+
+  return nil;
+}
+
 static val search_form(match_line_ctx *c, val needle_form, val from_end)
 {
   if (regexp(first(needle_form))) {
@@ -3250,6 +3265,7 @@ static void syms_init(void)
   times_k = intern(lit("times"), keyword_package);
   lines_k = intern(lit("lines"), keyword_package);
   chars_k = intern(lit("chars"), keyword_package);
+  text_s = intern(lit("text"), user_package);
   choose_s = intern(lit("choose"), user_package);
   gather_s = intern(lit("gather"), user_package);
   longest_k = intern(lit("longest"), keyword_package);
@@ -3306,6 +3322,7 @@ static void dir_tables_init(void)
   sethash(v_directive_table, filter_s, cptr((mem_t *) v_filter));
   sethash(v_directive_table, eof_s, cptr((mem_t *) v_eof));
 
+  sethash(h_directive_table, text_s, cptr((mem_t *) h_text));
   sethash(h_directive_table, var_s, cptr((mem_t *) h_var));
   sethash(h_directive_table, skip_s, cptr((mem_t *) h_skip));
   sethash(h_directive_table, coll_s, cptr((mem_t *) h_coll));