From 7094b78821bf4817af674284d2a40f070b46e894 Mon Sep 17 00:00:00 2001
From: Slava Pestov <slava@slava-pestovs-macbook-pro.local>
Date: Sun, 26 Apr 2009 21:22:06 -0500
Subject: [PATCH] Add firstn-unsafe, input<sequence-unsafe

---
 basis/combinators/smart/smart.factor         | 4 ++++
 basis/generalizations/generalizations.factor | 9 ++++++---
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/basis/combinators/smart/smart.factor b/basis/combinators/smart/smart.factor
index aa7960539c..9519847810 100644
--- a/basis/combinators/smart/smart.factor
+++ b/basis/combinators/smart/smart.factor
@@ -18,6 +18,10 @@ MACRO: input<sequence ( quot -- newquot )
     [ infer in>> ] keep
     '[ _ firstn @ ] ;
 
+MACRO: input<sequence-unsafe ( quot -- newquot )
+    [ infer in>> ] keep
+    '[ _ firstn-unsafe @ ] ;
+
 MACRO: reduce-outputs ( quot operation -- newquot )
     [ dup infer out>> 1 [-] ] dip n*quot compose ;
 
diff --git a/basis/generalizations/generalizations.factor b/basis/generalizations/generalizations.factor
index edee44acc6..139b7a528a 100644
--- a/basis/generalizations/generalizations.factor
+++ b/basis/generalizations/generalizations.factor
@@ -26,11 +26,14 @@ MACRO: narray ( n -- )
 MACRO: nsum ( n -- )
     1- [ + ] n*quot ;
 
+MACRO: firstn-unsafe ( n -- )
+    [ '[ [ _ ] dip nth-unsafe ] ] map '[ _ cleave ] ;
+
 MACRO: firstn ( n -- )
     dup zero? [ drop [ drop ] ] [
-        [ [ '[ [ _ ] dip nth-unsafe ] ] map ]
-        [ 1- '[ [ _ ] dip bounds-check 2drop ] ]
-        bi prefix '[ _ cleave ]
+        [ 1- swap bounds-check 2drop ]
+        [ firstn-unsafe ]
+        bi-curry '[ _ _ bi ]
     ] if ;
 
 MACRO: npick ( n -- )