lib/standard/ropes: Added an iterator on the leaves of the Rope.

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>

diff --git a/lib/standard/ropes.nit b/lib/standard/ropes.nit
index 01e09c4..b76784f 100644 (file)
--- a/lib/standard/ropes.nit
+++ b/lib/standard/ropes.nit
@@ -114,6 +114,9 @@ abstract class Rope
        # Iterator on the nodes of the rope, in forward postfix order
        private fun postfix(from: Int): Postfix do return new Postfix.from(self, from)
 
+       # Iterator on the leaves of the rope, forward order
+       private fun leaves(from: Int): LeavesIterator do return new LeavesIterator(self, from)
+
        # Path to the Leaf for `position`
        private fun node_at(position: Int): Path
        do
@@ -387,3 +390,33 @@ private class Postfix
        end
 end
 
+# Iterates on the leaves (substrings) of the Rope
+class LeavesIterator
+       super IndexedIterator[Leaf]
+
+       private var nodes: Postfix
+
+       init(tgt: Rope, pos: Int)
+       do
+               nodes = tgt.postfix(pos)
+       end
+
+       redef fun is_ok do return nodes.is_ok
+
+       redef fun item
+       do
+               assert is_ok
+               return nodes.item.as(Leaf)
+       end
+
+       redef fun index do return nodes.index
+
+       redef fun next
+       do
+               while nodes.is_ok do
+                       nodes.next
+                       if nodes.is_ok and nodes.item isa Leaf then break
+               end
+       end
+end
+