Subject: bug#17485: [PATCH 3/3] Reimplement reduce-right in srfi-1

From: David Kastrup <[email-masked]>
Date: Tue, 3 Jun 2014 20:56:18 +0200

* module/srfi/srfi-1.scm (reduce-right): Avoid use of drop-right in
  connection with last as a single upfront reverse is more efficient and
  simpler to understand.

Signed-off-by: David Kastrup <[email-masked]>
---
 module/srfi/srfi-1.scm | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/module/srfi/srfi-1.scm b/module/srfi/srfi-1.scm
index 73d164a..6aa249a 100644
--- a/module/srfi/srfi-1.scm
+++ b/module/srfi/srfi-1.scm
@@ -573,10 +573,7 @@ then that's the return value."
 F is on two elements from LST, rather than one element and a given
 initial value.  If LST is empty, RIDENTITY is returned.  If LST
 has just one element then that's the return value."
-  (check-arg procedure? f reduce)
-  (if (null? lst)
-      ridentity
-      (fold-right f (last lst) (drop-right lst 1))))
+  (reduce f ridentity (reverse lst)))
 
 (define map
   (case-lambda
-- 
1.9.1