From: Jean Privat <jean@pryen.org>
Date: Fri, 15 Aug 2014 19:55:50 +0000 (-0400)
Subject: lib: add Seq:insert_all as a generalized `insert`
X-Git-Tag: v0.6.8~16^2~2
X-Git-Url: http://nitlanguage.org

lib: add Seq:insert_all as a generalized `insert`

Signed-off-by: Jean Privat <jean@pryen.org>
---

diff --git a/lib/standard/collection/abstract_collection.nit b/lib/standard/collection/abstract_collection.nit
index 93d882a..b99c465 100644
--- a/lib/standard/collection/abstract_collection.nit
+++ b/lib/standard/collection/abstract_collection.nit
@@ -835,10 +835,30 @@ interface Sequence[E]
 	#     a.insert(100, 2)
 	#     assert a      ==  [10, 20, 100, 30, 40]
 	#
-	# REQUIRE `index >= 0 and index < length`
+	# REQUIRE `index >= 0 and index <= length`
 	# ENSURE `self[index] == item`
 	fun insert(item: E, index: Int) is abstract
 
+	# Insert all elements at a given position, following elements are shifted.
+	#
+	#     var a = [10, 20, 30, 40]
+	#     a.insert_all([100..102], 2)
+	#     assert a      ==  [10, 20, 100, 101, 102, 30, 40]
+	#
+	# REQUIRE `index >= 0 and index <= length`
+	# ENSURE `self[index] == coll.first`
+	fun insert_all(coll: Collection[E], index: Int)
+	do
+		assert index >= 0 and index < length
+		if index == length then
+			add_all(coll)
+		end
+		for c in coll do
+			insert(c, index)
+			index += 1
+		end
+	end
+
 	# Remove the item at `index` and shift all following elements
 	#
 	#     var a = [10,20,30]
diff --git a/lib/standard/collection/array.nit b/lib/standard/collection/array.nit
index e98ddea..9482c8f 100644
--- a/lib/standard/collection/array.nit
+++ b/lib/standard/collection/array.nit
@@ -186,6 +186,19 @@ abstract class AbstractArray[E]
 		self[pos] = item
 	end
 
+	redef fun insert_all(coll, pos)
+	do
+		var l = coll.length
+		if l == 0 then return
+		enlarge(length + l)
+		_length += l
+		copy_to(pos, length-pos-l, self, pos + l)
+		for c in coll do
+			self[pos] = c
+			pos += 1
+		end
+	end
+
 	redef fun add(item) do self[length] = item
 
 	redef fun clear do _length = 0