From: Chris Hanson <org/chris-hanson/cph>
Date: Wed, 21 Mar 2007 15:06:16 +0000 (+0000)
Subject: Implement REDUCE-LEFT, which has semantics of old REDUCE.
X-Git-Tag: 20090517-FFI~707
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=197f293583977e651134b3d3cfd60bfc0c0b1ea6;p=mit-scheme.git

Implement REDUCE-LEFT, which has semantics of old REDUCE.
---

diff --git a/v7/src/runtime/list.scm b/v7/src/runtime/list.scm
index b9a27e666..12e9436f6 100644
--- a/v7/src/runtime/list.scm
+++ b/v7/src/runtime/list.scm
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Id: list.scm,v 14.54 2007/01/05 21:19:28 cph Exp $
+$Id: list.scm,v 14.55 2007/03/21 15:06:09 cph Exp $
 
 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
     1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
@@ -717,6 +717,9 @@ USA.
 	    (error:not-list list 'REDUCE))
 	initial)))
 
+(define (reduce-left procedure initial list)
+  (reduce (lambda (a b) (procedure b a)) initial list))
+
 (define (reduce-right procedure initial list)
   (if (pair? list)
       (let loop ((first (car list)) (rest (cdr list)))
diff --git a/v7/src/runtime/runtime.pkg b/v7/src/runtime/runtime.pkg
index 2aace2f52..60f8068b2 100644
--- a/v7/src/runtime/runtime.pkg
+++ b/v7/src/runtime/runtime.pkg
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Id: runtime.pkg,v 14.612 2007/01/17 03:39:42 cph Exp $
+$Id: runtime.pkg,v 14.613 2007/03/21 15:06:16 cph Exp $
 
 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
     1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
@@ -2296,6 +2296,7 @@ USA.
 	  null?
 	  pair?
 	  reduce
+	  reduce-left
 	  reduce-right
 	  restricted-keyword-list?
 	  reverse