lib/array: suppress a warning to be compatible with the bootstrap

[nit.git] / lib / standard / collection / array.nit

diff --git a/lib/standard/collection/array.nit b/lib/standard/collection/array.nit
index 1fb8581..3cc0b57 100644 (file)
--- 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
 
@@ -477,6 +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]
@@ -618,8 +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