* match.c (v_gather): Implemented until/last clause.

* parser.y (gather_parts, additional_gather_parts): New nonterminals.
(gather_clause): Syntax refactored for until/last clause.

* txr.1: Updated.

1 files changed, 16 insertions, 0 deletions

diff --git a/txr.1 b/txr.1
index 8ba7afaf..69f1cc5e 100644
--- a/txr.1
+++ b/txr.1
@@ -1829,6 +1829,14 @@ The syntax follows this pattern
 Of course the multi-line clauses are optional.   The gather directive takes
 keyword parameters, see below.
 
+Similarly to @(collect), @(gather) has an optional until/last clause:
+
+  @(gather)
+  ...
+  @(until)
+  ...
+  @(end)
+
 How gather works is that the text is searched for matches for the single line
 and multi-line queries. The clauses are applied in the order in which they appear.
 Whenever one of the clauses matches, any bindings it produces are retained and
@@ -1849,6 +1857,14 @@ order:
   SHELL=@SHELL
   @(end)
 
+If the until or last clause is present and a match occurs, then the matches
+from the other clauses are discarded and the gather terminates. The difference
+between until and last is that any bindings bindings established in last are
+retained, and the input position is advanced past the matched material.
+The until/last clause has visibility to bindings established in the
+previous clauses in that same iteration, even though those bindings
+end up thrown away.
+
 .SS Gather Keyword Parameters
 
 The gather diretive accepts the keyword parameter :vars. The argument to vars is a list