dlist>seq now preserves f entries as reported by leifkb

basis/dlists/dlists-tests.factor

@@ -75,3 +75,7 @@ IN: dlists.tests
     dup clone 3 over push-back
     [ dlist>seq ] bi@
 ] unit-test
+
+[ V{ f 3 1 f } ] [ <dlist> 1 over push-front 3 over push-front f over push-front f over push-back dlist>seq ] unit-test
+
+[ V{ } ] [ <dlist> dlist>seq ] unit-test

basis/dlists/dlists.factor

@@ -154,7 +154,7 @@ M: dlist clear-deque ( dlist -- )
     [ obj>> ] prepose dlist-each-node ; inline
 
 : dlist>seq ( dlist -- seq )
-    [ ] pusher [ dlist-each ] dip ;
+    [ drop t ] pusher [ dlist-each ] dip ;
 
 : 1dlist ( obj -- dlist ) <dlist> [ push-front ] keep ;