Ralph Corderoy <ra...@inputplus.co.uk> wrote:
|> Unfortunately, this also means inventing a new syntax. How should
|> "\*", "\(", and "\[" be treated -- as groff escapes or as
|> regular-expression magic?
|
|Exactly. Taking an earlier suggestion for OR, it's valid now.
|
| $ nroff | grep .
| .if 'a'a'b'c'
| b’c’
| $
|
|However, a new syntax is needed. I'd guess something at the start that
|is currently invalid would indicate a whole new style of expression is
|present, one with typical precedence, and more string matching
|possibilities.
A really really ugly way of extending the current syntax today,
which possibly would do no harm in real life?, would be to let
a doubling of the delimiter mean that further tests follow, as in
.if 'abc'def''ghi''not this''abc' .tm matches
I have no idea, but the attached patch should do this pretty well.
Note i'm running groff(1) with my [file_case] extension and
without GNULib, but it applies somewhat:
?0[steffen@sherwood groff.git]$ gl1 15d0cd9 | s-patch
patching file src/roff/troff/input.cpp
Hunk #1 succeeded at 5766 (offset 5 lines).
?0[steffen@sherwood groff.git]$
I'm not sure i like this approach, though.
Ciao,
--steffen
commit 15d0cd9 (HEAD, refs/heads/file_case)
Author: Steffen Nurpmeso <sdao...@users.sf.net>
Date: 2014-11-13 16:42:38 +0100
Satisfy (hohe72 AT arcor DOT de): add ".if 'a'b''c''d''e'" pattern
---
src/roff/troff/input.cpp | 67 +++++++++++++++++++++++++++++-------------------
1 file changed, 40 insertions(+), 27 deletions(-)
diff --git a/src/roff/troff/input.cpp b/src/roff/troff/input.cpp
index e8ef0b9..8feb269 100644
--- a/src/roff/troff/input.cpp
+++ b/src/roff/troff/input.cpp
@@ -5761,36 +5761,49 @@ int do_if_request()
else if (tok.delimiter()) {
token delim = tok;
int delim_level = input_stack::get_level();
- environment env1(curenv);
- environment env2(curenv);
- environment *oldenv = curenv;
- curenv = &env1;
- suppress_push = 1;
- for (int i = 0; i < 2; i++) {
- for (;;) {
- tok.next();
- if (tok.newline() || tok.eof()) {
- warning(WARN_DELIM, "missing closing delimiter");
- tok.next();
- curenv = oldenv;
- return 0;
- }
- if (tok == delim
- && (compatible_flag || input_stack::get_level() == delim_level))
- break;
- tok.process();
+ environment *oldenv = curenv, env1(oldenv);
+ node *n1 = NULL;
+
+ result = 0;
+ for (bool any = false;;) {
+ suppress_push = 1;
+ environment env2(curenv = oldenv);
+jenv2:
+ for (curenv = any ? &env2 : &env1;;) {
+ tok.next();
+ if (tok.newline() || tok.eof()) {
+ warning(WARN_DELIM, "missing closing delimiter");
+ tok.next();
+ curenv = oldenv;
+ delete_node_list(n1);
+ return 0;
+ }
+ if (tok == delim &&
+ (compatible_flag || input_stack::get_level() == delim_level))
+ break;
+ tok.process();
}
- curenv = &env2;
+
+ if (!any) {
+ any = true;
+ n1 = env1.extract_output_line();
+ goto jenv2; // Cheaper than continue;
+ }
+ if (result == 0) {
+ node *n2 = env2.extract_output_line();
+ result = same_node_list(n1, n2);
+ delete_node_list(n2);
+ }
+
+ curenv = oldenv;
+ have_input = 0;
+ suppress_push = 0;
+ tok.next();
+ if (tok != delim)
+ break;
}
- node *n1 = env1.extract_output_line();
- node *n2 = env2.extract_output_line();
- result = same_node_list(n1, n2);
+
delete_node_list(n1);
- delete_node_list(n2);
- curenv = oldenv;
- have_input = 0;
- suppress_push = 0;
- tok.next();
}
else {
units n;
