From a42b872a23859635459e11522d11b20217df0997 Mon Sep 17 00:00:00 2001
From: Doug Coleman <erg@jobim.local>
Date: Fri, 3 Apr 2009 12:40:45 -0500
Subject: [PATCH] fix bug in take-sequence

---
 extra/html/parser/state/state-tests.factor |  3 +++
 extra/html/parser/state/state.factor       | 11 +++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/extra/html/parser/state/state-tests.factor b/extra/html/parser/state/state-tests.factor
index 75db1a373e..c8a8a95892 100644
--- a/extra/html/parser/state/state-tests.factor
+++ b/extra/html/parser/state/state-tests.factor
@@ -99,3 +99,6 @@ IN: html.parser.state.tests
 
 [ "" ]
 [ "abc" <state-parser> dup "abc" take-sequence drop take-rest ] unit-test
+
+[ f ]
+[ "abc" <state-parser> "abcdefg" take-sequence ] unit-test
diff --git a/extra/html/parser/state/state.factor b/extra/html/parser/state/state.factor
index 5f845ce810..2bcd08be5f 100644
--- a/extra/html/parser/state/state.factor
+++ b/extra/html/parser/state/state.factor
@@ -51,9 +51,16 @@ TUPLE: state-parser sequence n ;
 : take-while ( state-parser quot: ( obj -- ? ) -- sequence/f )
     [ not ] compose take-until ; inline
 
+: <safe-slice> ( from to seq -- slice/f )
+    3dup {
+        [ 2drop 0 < ]
+        [ [ drop ] 2dip length > ]
+        [ drop > ]
+    } 3|| [ 3drop f ] [ slice boa ] if ; inline
+
 :: take-sequence ( state-parser sequence -- obj/f )
-    state-parser [ n>> dup sequence length + ] [ sequence>> ] bi <slice>
-    sequence sequence= [
+    state-parser [ n>> dup sequence length + ] [ sequence>> ] bi
+    <safe-slice> sequence sequence= [
         sequence
         state-parser [ sequence length + ] change-n drop
     ] [