Reimplement leach so that stack is clean when executing the quotation

The previous implementation let garbage on the stack (such as the lazy list
cdr) before executing the quotation. This prevents easy implementation of
reduce-like words using leach.

diff --git a/extra/lazy-lists/lazy-lists.factor b/extra/lazy-lists/lazy-lists.factor
index 2e3dc9154a25ab03fc1158adda9b0f38336fd1a4..c6294087045f64cc3ad9f748118fea88518ca00f 100644 (file)
--- a/extra/lazy-lists/lazy-lists.factor
+++ b/extra/lazy-lists/lazy-lists.factor
@@ -100,11 +100,7 @@ M: lazy-cons list? ( object -- bool )
     dup car swap cdr ;
 
 : leach ( list quot -- )
-  swap dup nil? [
-    2drop
-  ] [
-    uncons swap pick call swap leach
-  ] if ;
+  swap dup nil? [ 2drop ] [ uncons swapd over 2slip leach ] if ; inline
 
 TUPLE: memoized-cons original car cdr nil? ;