From a592f3a37b3df86851dab32dca6f7c7db19c22d8 Mon Sep 17 00:00:00 2001
From: Doug Coleman <erg@jjjj.local>
Date: Sun, 13 Jan 2008 08:02:41 -1000
Subject: [PATCH] make singleton? foldable

---
 extra/sequences/lib/lib.factor | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/extra/sequences/lib/lib.factor b/extra/sequences/lib/lib.factor
index e46ce3b107..37b00042d2 100755
--- a/extra/sequences/lib/lib.factor
+++ b/extra/sequences/lib/lib.factor
@@ -59,7 +59,7 @@ IN: sequences.lib
     ] { } make ;
 
 : singleton? ( seq -- ? )
-    length 1 = ;
+    length 1 = ; foldable
 
 : delete-random ( seq -- value )
     [ length random ] keep [ nth ] 2keep delete-nth ;