boyer-moore: simplify M\ sequence search-from.

diff --git a/extra/boyer-moore/boyer-moore.factor b/extra/boyer-moore/boyer-moore.factor
index aba3f614a12642c7e5bd9e0d55d97603f39545e6..1775b94c17ef2d68224d775c7ac838bcb4bb6515 100644 (file)
--- a/extra/boyer-moore/boyer-moore.factor
+++ b/extra/boyer-moore/boyer-moore.factor
@@ -70,8 +70,7 @@ PRIVATE>
 GENERIC: search-from ( seq from obj -- i/f )
 
 M: sequence search-from
-    dup length zero?
-    [ 3drop 0 ] [ <boyer-moore> (search-from) ] if ;
+    [ 2drop 0 ] [ <boyer-moore> (search-from) ] if-empty ;
 
 M: boyer-moore search-from (search-from) ;