From fc85d095600162567fd0aa563eed9e6eada3e889 Mon Sep 17 00:00:00 2001
From: Mikael Djurfeldt <djurfeldt@nada.kth.se>
Date: Mon, 9 Dec 2002 12:58:52 +0000
Subject: [PATCH] * threads.scm (letpar): New macro.

---
 ice-9/ChangeLog   | 7 ++++++-
 ice-9/threads.scm | 8 ++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/ice-9/ChangeLog b/ice-9/ChangeLog
index bca320e72..456603177 100644
--- a/ice-9/ChangeLog
+++ b/ice-9/ChangeLog
@@ -1,3 +1,7 @@
+2002-12-09  Mikael Djurfeldt  <djurfeldt@nada.kth.se>
+
+	* threads.scm (letpar): New macro.
+
 2002-12-08  Rob Browning  <rlb@defaultvalue.org>
 
 	* debugger/breakpoints/Makefile.am (subpkgdatadir): VERSION ->
@@ -10,7 +14,8 @@
 
 2002-12-04  Mikael Djurfeldt  <mdj@linnaeus>
 
-	* threads.scm (par-map, par-for-each, parallel): 
+	* threads.scm (parallel): New macro.
+	 (par-map, par-for-each): New procedures.
 
 	* documentation.scm (object-documentation): Added support for
 	defmacros.
diff --git a/ice-9/threads.scm b/ice-9/threads.scm
index c552a8596..f5d178a4e 100644
--- a/ice-9/threads.scm
+++ b/ice-9/threads.scm
@@ -63,6 +63,7 @@
   :export-syntax (make-thread
 		  begin-thread
 		  parallel
+		  letpar
 		  with-mutex
 		  monitor))
 
@@ -188,6 +189,13 @@
 	      (wait-condition-variable ,c ,m)
 	      (values ,@vars))))))
 
+(defmacro letpar (bindings . body)
+  `(call-with-values
+       (lambda ()
+	 (parallel ,@(map cadr bindings)))
+     (lambda ,(map car bindings)
+       ,@body)))
+
 (defmacro with-mutex (m . body)
   `(dynamic-wind
        (lambda () (lock-mutex ,m))