X-Git-Url: http://nitlanguage.org

diff --git a/lib/core/text/ropes.nit b/lib/core/text/ropes.nit
index f370e49..f57b33d 100644
--- a/lib/core/text/ropes.nit
+++ b/lib/core/text/ropes.nit
@@ -221,23 +221,16 @@ private class Concat
 	end
 
 	redef fun copy_to_native(dest, n, src_offset, dest_offset) do
-		var subs = new RopeSubstrings.from(self, src_offset)
-		var st = src_offset - subs.pos
-		var off = dest_offset
-		while n > 0 do
-			var it = subs.item
-			if n > it.length then
-				var cplen = it.length - st
-				it._items.copy_to(dest, cplen, st, off)
-				off += cplen
-				n -= cplen
-			else
-				it._items.copy_to(dest, n, st, off)
-				n = 0
-			end
-			subs.next
-			st = 0
+		var l = _left
+		if src_offset < l.bytelen then
+			var lcopy = l.bytelen - src_offset
+			lcopy = if lcopy > n then n else lcopy
+			l.copy_to_native(dest, lcopy, src_offset, dest_offset)
+			dest_offset += lcopy
+			n -= lcopy
+			src_offset = 0
 		end
+		_right.copy_to_native(dest, n, src_offset, dest_offset)
 	end
 
 	# Returns a balanced version of `self`
@@ -828,7 +821,7 @@ private class ReverseRopeSubstrings
 	redef fun next do
 		if pos < 0 then return
 		var curr = iter.prev
-		var currit = curr.node
+		var currit = curr.as(not null).node
 		while curr != null do
 			currit = curr.node
 			if not currit isa Concat then
@@ -935,14 +928,14 @@ private class RopeSubstrings
 	redef fun next do
 		pos += str.length
 		if pos > max then return
-		var it = iter.prev
+		var it = iter.prev.as(not null)
 		var rnod = it.node
 		loop
 			if not rnod isa Concat then
 				it.ldone = true
 				it.rdone = true
 				str = rnod.as(FlatString)
-				iter = it.as(not null)
+				iter = it
 				break
 			end
 			if not it.ldone then
@@ -954,7 +947,7 @@ private class RopeSubstrings
 				rnod = rnod._right
 				it = new RopeCharIteratorPiece(rnod, false, false, it)
 			else
-				it = it.prev
+				it = it.prev.as(not null)
 				rnod = it.node
 				continue
 			end