From 3beebc10becc63a2a0f10ccb787afe47382e141e Mon Sep 17 00:00:00 2001
From: Jean Privat <jean@pryen.org>
Date: Fri, 10 Jul 2009 15:48:07 -0400
Subject: [PATCH] lib: improve list iterator

Signed-off-by: Jean Privat <jean@pryen.org>
---
 lib/standard/list.nit    |   24 ++++++++++++++++++++----
 tests/sav/test_list2.sav |    3 +++
 tests/test_list2.nit     |   33 +++++++++++++++++++++++++++++++++
 3 files changed, 56 insertions(+), 4 deletions(-)
 create mode 100644 tests/sav/test_list2.sav
 create mode 100644 tests/test_list2.nit

diff --git a/lib/standard/list.nit b/lib/standard/list.nit
index 13a8e29..ec803ba 100644
--- a/lib/standard/list.nit
+++ b/lib/standard/list.nit
@@ -170,7 +170,7 @@ special IndexedCollection[E]
 	end
 
 
-	redef fun iterator: ListIterator[E] do return new ListIterator[E](_head)
+	redef fun iterator: ListIterator[E] do return new ListIterator[E](self)
 
 	# Build an empty list.
 	init do end
@@ -245,7 +245,7 @@ class ListIterator[E]
 special IndexedIterator[E]
 	redef fun item do return _node.item
 
-	# redef fun item=(e) do _node.item = e
+	fun item=(e: E) do _node.item = e
 
 	redef fun is_ok do return not _node == null
 
@@ -256,17 +256,33 @@ special IndexedIterator[E]
 	end
 
 	# Build a new iterator from `node'.
-	private init(node: nullable ListNode[E])
+	private init(list: List[E])
 	do
-		_node = node
+		_list = list
+		_node = list._head
 		_index = 0
 	end
 
+	# The current list
+	var _list: List[E]
+
 	# The current node of the list
 	var _node: nullable ListNode[E]
 
 	# The index of the current node
 	redef readable var _index: Int
+
+	# Remove the current item
+	fun delete
+	do
+		_list.remove_node(_node.as(not null))
+	end
+
+	# Insert before the current item
+	fun insert_before(element: E)
+	do
+		_list.insert_before(element, _node.as(not null))
+	end
 end
 
 # Linked nodes that constitute a linked list.
diff --git a/tests/sav/test_list2.sav b/tests/sav/test_list2.sav
new file mode 100644
index 0000000..8fc8aa8
--- /dev/null
+++ b/tests/sav/test_list2.sav
@@ -0,0 +1,3 @@
+1, 2, 3, 4, 5, 6
+11, 12, 13, 14, 15, 16
+1, 21, 2, 22, 3, 23, 4, 24, 5, 25, 6, 26
diff --git a/tests/test_list2.nit b/tests/test_list2.nit
new file mode 100644
index 0000000..ab0290b
--- /dev/null
+++ b/tests/test_list2.nit
@@ -0,0 +1,33 @@
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Copyright 2009 Jean Privat <jean@pryen.org>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+var l = new List[Int]
+l.add_all([1, 2, 3, 4, 5, 6])
+print l.join(", ")
+var it = l.iterator
+while it.is_ok do
+	it.item += 10
+	it.next
+end
+print l.join(", ")
+var it = l.iterator
+while it.is_ok do
+	it.insert_before(it.item-10)
+	it.insert_before(it.item+10)
+	it.delete
+	it.next
+end
+print l.join(", ")
-- 
1.7.9.5