From: John Benediktsson <mrjbq7@gmail.com>
Date: Tue, 25 Jan 2022 17:55:57 +0000 (-0800)
Subject: Revert "Revert "sequences: unslicing in binary-reduce""
X-Git-Tag: 0.99~1677
X-Git-Url: https://gitweb.factorcode.org/gitweb.cgi?p=factor.git;a=commitdiff_plain;h=6148cb2061691fb0617eff3dd9b8c7044b630bba

Revert "Revert "sequences: unslicing in binary-reduce""

This reverts commit 0e9427d874a9f4d683c0b58eba84b3f7ad8a49f3.
---

diff --git a/core/sequences/sequences.factor b/core/sequences/sequences.factor
index b1524145d4..f090543020 100644
--- a/core/sequences/sequences.factor
+++ b/core/sequences/sequences.factor
@@ -1017,7 +1017,11 @@ PRIVATE>
 PRIVATE>
 
 : binary-reduce ( seq start quot: ( elt1 elt2 -- newelt ) -- value )
-    pick length 0 max 0 swap (binary-reduce) ; inline
+    pick dup slice? [
+        [ seq>> ] 3dip [ from>> 0 max ] [ to>> 0 max over - ] bi
+    ] [
+        length 0 max 0 swap
+    ] if (binary-reduce) ; inline
 
 : cut ( seq n -- before after )
     [ head ] [ tail ] 2bi ;