Filtering feature for variable substitution in output.

* filter.c, filter.h: New files.

* Makefile (OBJS): filter.o added.

* gc.c (mark_obj): Mark new alloc field of string objets.

* hash.c (struct hash): New member, userdata.
(hash_mark): Mark new userdata member of hash.
(make_hash): Initialize userdata.
(get_hash_userdata, set_hash_userdata, hashp): New functions.

* hash.h (get_hash_userdata, set_hash_userdata, hashp): New functions
declared.

* lib.c (getplist, string_extend, cobjp): New functions.
(string_own, string, string_utf8): Initialize new alloc field to nil.
(mkstring, mkustring): Initialize new alloc field to actual size.
(length_str): When length is computed and cached, also compute
and cache alloc.
(init): Call filter_init.

* lib.h (string string): New member, alloc.
(num_fast): Macro converted to inline function.
(getplist, string_extend, cobjp): New functions declared.

* match.c (match_line): Follows change of modifier s-exp syntax.
(format_field): New parameter, filter.
New modifier syntax parsed. Filter retrieved, and applied.
(subst_vars): New parameter, filter. Filter is either applied
in this function or passed to format_field, as needed.
(eval_form): Pass nil to new parameter of subst_vars.
(do_output_line): New parameter, filter. Passed down to subst_vars.
(do_output): New parameter, filter. Passed down to do_output_line.
(match_files): Pass nil filter to subst_vars in cat directive.
Output directive refactored to parse keywords, extract the
filter and pass down to do_output.

* parser.y (regex): Generate (sys:regex regex syntax ...)
instead of (regex syntax ...).
(elem, expr): Updated w.r.t. regex syntax change.
(var): Cases '{' IDENT regex '}' and '{' IDENT NUMBER '}'
are removed. new syntax '{' IDENT exprs '}' to handle these
more generally and allow for keywords.

* txr.1: Updated.

1 files changed, 4 insertions, 0 deletions

diff --git a/hash.h b/hash.h
index cd293ce9..b5bd200a 100644
--- a/hash.h
+++ b/hash.h
@@ -28,8 +28,12 @@ val hash_obj(val);
 val make_hash(val weak_keys, val weak_vals);
 val *gethash_l(val hash, val key, val *new_p);
 val gethash(val hash, val key);
+val gethash_f(val hash, val key, val *found);
 val sethash(val hash, val key, val value);
 val remhash(val hash, val key);
+val get_hash_userdata(val hash);
+val set_hash_userdata(val hash, val data);
+val hashp(val obj);
 void hash_process_weak(void);
 
 void hash_init(void);