From cd86eb8febeb04120c601c314cbff2159743ce7a Mon Sep 17 00:00:00 2001
From: Daniel Ehrenberg <ehrenbed@carleton.edu>
Date: Mon, 17 Dec 2007 00:42:41 -0500
Subject: [PATCH] Sequence hashcode

---
 core/sequences/sequences.factor | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/core/sequences/sequences.factor b/core/sequences/sequences.factor
index 01443716e7..92e160f3bf 100755
--- a/core/sequences/sequences.factor
+++ b/core/sequences/sequences.factor
@@ -674,9 +674,13 @@ PRIVATE>
 !        hashcode* >fixnum swap 31 fixnum*fast fixnum+fast
 !    ] curry* each ; inline
 
+: sequence-hashcode-step ( oldhash newpart -- newhash )
+    swap [
+        dup -2 shift swap 5 shift
+        fixnum+fast fixnum+fast
+    ] keep bitxor ;
+
 : sequence-hashcode ( n seq -- x )
     0 -rot [
-        hashcode* >fixnum swap
-        [ -2 shift fixnum+fast ] keep [ 5 shift fixnum+fast ] keep
-        bitxor
+        hashcode* >fixnum sequence-hashcode-step
     ] curry* each ; inline