From: chris.double <chris.double@double.co.nz>
Date: Sun, 8 Oct 2006 10:44:34 +0000 (+0000)
Subject: contrib/sequences: add ?head-slice, ?tail-slice, etc
X-Git-Url: https://gitweb.factorcode.org/gitweb.cgi?p=factor.git;a=commitdiff_plain;h=a7798e06d0a816e655305f44263856bf53d1570b

contrib/sequences: add ?head-slice, ?tail-slice, etc
---

diff --git a/contrib/sequences.factor b/contrib/sequences.factor
index 4980022008..5ec775dad5 100644
--- a/contrib/sequences.factor
+++ b/contrib/sequences.factor
@@ -39,4 +39,13 @@ IN: sequences-contrib
 : trim* ( seq quot -- newseq ) [ (ltrim*) ] keep rtrim* ;
 : trim ( seq -- newseq ) [ blank? ] trim* ;
 
+: ?head-slice ( seq begin -- newseq ? )
+  2dup head? [ length tail-slice t ] [ drop f ] if ;
+
+: ?tail-slice ( seq end -- newseq ? )
+  2dup tail? [ length head-slice* t ] [ drop f ] if ;
+
+: unclip-slice ( seq -- rest first )
+  dup 1 tail-slice swap first ;
+
 PROVIDE: contrib/sequences ;