sequences.extras: cleanup change-last{-unsafe}

diff --git a/extra/sequences/extras/extras.factor b/extra/sequences/extras/extras.factor
index 1cc541f163e751507503760c400199994c707f18..2d3b67ed14c8dc88bda5e97d770156e162ef96ea 100644 (file)
--- a/extra/sequences/extras/extras.factor
+++ b/extra/sequences/extras/extras.factor
@@ -634,10 +634,10 @@ PRIVATE>
     ] if-empty ;
 
 : change-last ( seq quot -- )
-    [ drop length 1 - ] [ change-nth ] 2bi ; inline
+    [ index-of-last ] [ change-nth ] bi* ; inline
 
 : change-last-unsafe ( seq quot -- )
-    [ drop length 1 - ] [ change-nth-unsafe ] 2bi ; inline
+    [ index-of-last ] [ change-nth-unsafe ] bi* ; inline
 
 : replicate-into ( ... seq quot: ( ... -- ... newelt ) -- ... )
     over [ length ] 2dip '[ _ dip _ set-nth-unsafe ] each-integer ; inline