From c2aca44b4a9c12c0b4f1a25c83f889b93af92828 Mon Sep 17 00:00:00 2001
From: Slava Pestov <slava@factorcode.org>
Date: Sat, 29 Jan 2011 00:18:36 -0500
Subject: [PATCH] sequences: nths should return a sequence of the same type as
 the original (reported by Jon Harper)

---
 core/sequences/sequences-tests.factor | 2 ++
 core/sequences/sequences.factor       | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/core/sequences/sequences-tests.factor b/core/sequences/sequences-tests.factor
index 175ab252e1..586e312edb 100644
--- a/core/sequences/sequences-tests.factor
+++ b/core/sequences/sequences-tests.factor
@@ -255,6 +255,8 @@ unit-test
 [ { "a" "b" "c" "d" } ] [ { 0 1 2 3 } { "a" "b" "c" "d" } nths ] unit-test
 [ { "d" "c" "b" "a" } ] [ { 3 2 1 0 } { "a" "b" "c" "d" } nths ] unit-test
 [ { "d" "a" "b" "c" } ] [ { 3 0 1 2 } { "a" "b" "c" "d" } nths ] unit-test
+
+[ "dac" ] [ { 3 0 2 } "abcd" nths ] unit-test
                           
 TUPLE: bogus-hashcode ;
 
diff --git a/core/sequences/sequences.factor b/core/sequences/sequences.factor
index 55398ff02b..493365db1a 100644
--- a/core/sequences/sequences.factor
+++ b/core/sequences/sequences.factor
@@ -1,4 +1,4 @@
-! Copyright (C) 2005, 2010 Slava Pestov, Daniel Ehrenberg.
+! Copyright (C) 2005, 2011 Slava Pestov, Daniel Ehrenberg.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: accessors kernel kernel.private slots.private math
 math.private math.order ;
@@ -559,7 +559,7 @@ PRIVATE>
     [ [ (indices) ] 2curry each-index ] keep ;
 
 : nths ( indices seq -- seq' )
-    [ nth ] curry map ;
+    [ [ nth ] curry ] keep map-as ;
 
 : any? ( ... seq quot: ( ... elt -- ... ? ) -- ... ? )
     find drop >boolean ; inline