From 3decf306260c9729cc4391c483cda8aad96c016a Mon Sep 17 00:00:00 2001
From: John Benediktsson <mrjbq7@gmail.com>
Date: Wed, 19 Sep 2012 10:07:03 -0700
Subject: [PATCH] sequences: adding second-, third-, and fourth- unsafe words.

---
 core/sequences/sequences.factor | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/core/sequences/sequences.factor b/core/sequences/sequences.factor
index fcae61044e..4203fcb85c 100644
--- a/core/sequences/sequences.factor
+++ b/core/sequences/sequences.factor
@@ -113,17 +113,19 @@ INSTANCE: iota immutable-sequence
 
 <PRIVATE
 
-: first-unsafe ( seq -- first )
-    0 swap nth-unsafe ; inline
+: first-unsafe ( seq -- first ) 0 swap nth-unsafe ; inline
+: second-unsafe ( seq -- second ) 1 swap nth-unsafe ; inline
+: third-unsafe ( seq -- third ) 2 swap nth-unsafe ; inline
+: fourth-unsafe ( seq -- fourth ) 3 swap nth-unsafe ; inline
 
 : first2-unsafe ( seq -- first second )
-    [ first-unsafe ] [ 1 swap nth-unsafe ] bi ; inline
+    [ first-unsafe ] [ second-unsafe ] bi ; inline
 
 : first3-unsafe ( seq -- first second third )
-    [ first2-unsafe ] [ 2 swap nth-unsafe ] bi ; inline
+    [ first2-unsafe ] [ third-unsafe ] bi ; inline
 
 : first4-unsafe ( seq -- first second third fourth )
-    [ first3-unsafe ] [ 3 swap nth-unsafe ] bi ; inline
+    [ first3-unsafe ] [ fourth-unsafe ] bi ; inline
 
 : exchange-unsafe ( m n seq -- )
     [ [ nth-unsafe ] curry bi@ ]