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

diff --git a/lib/standard/collection/array.nit b/lib/standard/collection/array.nit
index ae351cf..3cc0b57 100644
--- a/lib/standard/collection/array.nit
+++ b/lib/standard/collection/array.nit
@@ -13,7 +13,9 @@
 
 # This module introduces the standard array structure.
 # It also implements two other abstract collections : ArrayMap and ArraySet
-module array
+module array is
+	no_warning "useless-type-test" # to avoid warning with nitc while compiling with c_src
+end
 
 import abstract_collection
 
@@ -130,7 +132,20 @@ abstract class AbstractArrayRead[E]
 		end
 	end
 
-	redef fun iterator: ArrayIterator[E] do return new ArrayIterator[E](self)
+	redef fun iterator: ArrayIterator[E] do
+		var res = _free_iterator
+		if res == null then return new ArrayIterator[E](self)
+		res._index = 0
+		_free_iterator = null
+		return res
+	end
+
+	# An old iterator, free to reuse.
+	# Once an iterator is `finish`, it become reusable.
+	# Since some arrays are iterated a lot, this avoid most of the
+	# continuous allocation/garbage-collection of the needed iterators.
+	private var free_iterator: nullable ArrayIterator[E] = null
+
 	redef fun reverse_iterator do return new ArrayReverseIterator[E](self)
 end
 
@@ -252,6 +267,7 @@ end
 #     assert a == b
 class Array[E]
 	super AbstractArray[E]
+	super Cloneable
 
 	redef fun [](index)
 	do
@@ -393,6 +409,29 @@ class Array[E]
 		return true
 	end
 
+	# Shallow clone of `self`
+	#
+	# ~~~
+	# var a = [1,2,3]
+	# var b = a.clone
+	# assert a == b
+	# a.add 4
+	# assert a != b
+	# b.add 4
+	# assert a == b
+	# ~~~
+	#
+	# Note that the clone is shallow and elements are shared between `self` and the result.
+	#
+	# ~~~
+	# var aa = [a]
+	# var bb = aa.clone
+	# assert aa == bb
+	# aa.first.add 5
+	# assert aa == bb
+	# ~~~
+	redef fun clone do return to_a
+
 	# Concatenation of arrays.
 	#
 	# Returns a new array built by concatenating `self` and `other` together.
@@ -453,6 +492,8 @@ private class ArrayIterator[E]
 	redef var index = 0
 
 	var array: AbstractArrayRead[E]
+
+	redef fun finish do _array._free_iterator = self
 end
 
 private class ArrayReverseIterator[E]
@@ -473,6 +514,7 @@ end
 # A set implemented with an Array.
 class ArraySet[E]
 	super Set[E]
+	super Cloneable
 
 	# The stored elements.
 	private var array: Array[E] is noinit
@@ -519,6 +561,37 @@ class ArraySet[E]
 	init with_capacity(i: Int) do _array = new Array[E].with_capacity(i)
 
 	redef fun new_set do return new ArraySet[E]
+
+	# Shallow clone of `self`
+	#
+	# ~~~
+	# var a = new ArraySet[Int]
+	# a.add 1
+	# a.add 2
+	# var b = a.clone
+	# assert a == b
+	# a.add 3
+	# assert a != b
+	# b.add 3
+	# assert a == b
+	# ~~~
+	#
+	# Note that the clone is shallow and keys and values are shared between `self` and the result.
+	#
+	# ~~~
+	# var aa = new ArraySet[Array[Int]]
+	# aa.add([1,2])
+	# var bb = aa.clone
+	# assert aa == bb
+	# aa.first.add 5
+	# assert aa == bb
+	# ~~~
+	redef fun clone
+	do
+		var res = new ArraySet[E]
+		res.add_all self
+		return res
+	end
 end
 
 # Iterators on sets implemented with arrays.
@@ -538,6 +611,7 @@ end
 # Associative arrays implemented with an array of (key, value) pairs.
 class ArrayMap[K, E]
 	super CoupleMap[K, E]
+	super Cloneable
 
 	# O(n)
 	redef fun [](key)
@@ -561,8 +635,8 @@ class ArrayMap[K, E]
 		end
 	end
 
-	redef var keys: RemovableCollection[K] = new ArrayMapKeys[K, E](self)
-	redef var values: RemovableCollection[E] = new ArrayMapValues[K, E](self)
+	redef var keys: RemovableCollection[K] = new ArrayMapKeys[K, E](self) is lazy
+	redef var values: RemovableCollection[E] = new ArrayMapValues[K, E](self) is lazy
 
 	# O(1)
 	redef fun length do return _items.length
@@ -616,6 +690,35 @@ class ArrayMap[K, E]
 		end
 		return -1
 	end
+
+	# Shallow clone of `self`
+	#
+	# ~~~
+	# var a = new ArrayMap[String,Int]
+	# a["one"] = 1
+	# a["two"] = 2
+	# var b = a.clone
+	# assert a == b
+	# a["zero"] = 0
+	# assert a != b
+	# ~~~
+	#
+	# Note that the clone is shallow and keys and values are shared between `self` and the result.
+	#
+	# ~~~
+	# var aa = new ArrayMap[String, Array[Int]]
+	# aa["two"] = [1,2]
+	# var bb = aa.clone
+	# assert aa == bb
+	# aa["two"].add 5
+	# assert aa == bb
+	# ~~~
+	redef fun clone
+	do
+		var res = new ArrayMap[K,E]
+		res.recover_with self
+		return res
+	end
 end
 
 private class ArrayMapKeys[K, E]