if-empty changes

[factor.git] / extra / units / units.factor

diff --git a/extra/units/units.factor b/extra/units/units.factor
index 7604108b82cd00d9b130fa95cb8b9db52e0cc0f9..02005fcd1f6c4143f2dc928a0c817204d48383ac 100755 (executable)
--- a/extra/units/units.factor
+++ b/extra/units/units.factor
@@ -19,8 +19,8 @@ M: dimensions-not-equal summary drop "Dimensions do not match" ;
     [ remove-one ] curry bi@ ;
 
 : symbolic-reduce ( seq seq -- seq seq )
-    2dup intersect dup empty?
-    [ drop ] [ first 2remove-one symbolic-reduce ] if ;
+    2dup intersect
+    [ first 2remove-one symbolic-reduce ] unless-empty ;
 
 : <dimensioned> ( n top bot -- obj )
     symbolic-reduce