public void ForEach(ArrayCallback callback) { }
bool Equals(ArrayCallback other) => other != null && other._item1 == _item1 && other._item2 == _item2;
bool Equals(ArrayCallback other) => other != null && EqualsObj(other._item1, _item1) && other._item2 == _item2;
bool Equals(ArrayCallback other) => other != null && EqualsObj(other._obj, _obj) && other._method == _method;
public extern void ForEach(ArrayCallback callback);