diff --git a/extra/combinators/lib/lib.factor b/extra/combinators/lib/lib.factor
index 7c93f805cd..6f1fbbe2c0 100755
--- a/extra/combinators/lib/lib.factor
+++ b/extra/combinators/lib/lib.factor
@@ -8,13 +8,6 @@ continuations ;
 
 IN: combinators.lib
 
-! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-
-: generate ( generator predicate -- obj )
-    #! Call 'generator' until the result satisfies 'predicate'.
-    [ slip over slip ] 2keep
-    roll [ 2drop ] [ rot drop generate ] if ; inline
-
 ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 ! Generalized versions of core combinators
 ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
@@ -165,3 +158,10 @@ MACRO: construct-slots ( assoc tuple-class -- tuple )
 
 : retry ( quot n -- )
     [ drop ] rot compose attempt-all ; inline
+
+: do-while ( pred body tail -- )
+    >r tuck 2slip r> while ;
+
+: generate ( generator predicate -- obj )
+    [ dup ] swap [ dup [ nip ] unless not ] 3compose
+    swap [ ] do-while ;