From 76c76b81ed2c92b44ac0ac40a87418410a7df847 Mon Sep 17 00:00:00 2001
From: Samuel Tardieu <sam@rfc1149.net>
Date: Thu, 27 Dec 2007 03:42:19 +0100
Subject: [PATCH] Simplify lazy-append nil? word

lazy-append tuples are always built using lappend. If list1 is nil, then
list2 is returned, hence nil? on a lazy-append object is always false.
---
 extra/lazy-lists/lazy-lists.factor | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/extra/lazy-lists/lazy-lists.factor b/extra/lazy-lists/lazy-lists.factor
index daf02eef22..c42daabc05 100644
--- a/extra/lazy-lists/lazy-lists.factor
+++ b/extra/lazy-lists/lazy-lists.factor
@@ -310,11 +310,7 @@ M: lazy-append cdr ( lazy-append -- cdr )
   lazy-append-list2 lappend ;
 
 M: lazy-append nil? ( lazy-append -- bool )
-  dup lazy-append-list1 nil? [
-    lazy-append-list2 nil?
-  ] [
-    drop f
-  ] if ;
+   drop f ;
 
 M: lazy-append list? ( object -- bool )
   drop t ;