From 5402162df517499097194b08e063dde0eaf33b8d Mon Sep 17 00:00:00 2001
From: Slava Pestov <slava@slava-pestovs-macbook-pro.local>
Date: Thu, 27 Nov 2008 21:07:50 -0600
Subject: [PATCH] Add mnswap macro

---
 basis/generalizations/generalizations-tests.factor | 4 ++++
 basis/generalizations/generalizations.factor       | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/basis/generalizations/generalizations-tests.factor b/basis/generalizations/generalizations-tests.factor
index 1ebe528f35..1291012700 100644
--- a/basis/generalizations/generalizations-tests.factor
+++ b/basis/generalizations/generalizations-tests.factor
@@ -38,3 +38,7 @@ IN: generalizations.tests
 [ "a" ] [ { "a" } 1 firstn ] unit-test
 
 [ [ 1 2 ] ] [ 1 2 2 [ ] nsequence ] unit-test
+
+[ 4 5 1 2 3 ] [ 1 2 3 4 5 2 3 mnswap ] unit-test
+
+[ 1 2 3 4 5 6 ] [ 1 2 3 4 5 6 2 4 mnswap 4 2 mnswap ] unit-test
diff --git a/basis/generalizations/generalizations.factor b/basis/generalizations/generalizations.factor
index 490fa77204..b8d8db019c 100644
--- a/basis/generalizations/generalizations.factor
+++ b/basis/generalizations/generalizations.factor
@@ -73,3 +73,6 @@ MACRO: napply ( n -- )
     2 [a,b]
     [ [ 1- ] [ ] bi '[ _ ntuck _ nslip ] ]
     map concat >quotation [ call ] append ;
+
+MACRO: mnswap ( m n -- )
+    1+ '[ _ -nrot ] <repetition> spread>quot ;