Given this little class:

package testing {
import mx.collections.IList;
import mx.collections.ArrayCollection;
public class Clazz {
public var aList : IList = new ArrayCollection();

public function foo() : void {
var anotherArray : ArrayCollection = new ArrayCollection();
aList = anotherArray;

}
}
}

IDEA will warn me that the initializer assigning aList is "not assignable to IList", even though ArrayCollection inherits ListCollectionView, which does implement IList. About the same warning appears in the foo() method, though not in an initializer. It compiles without problems!

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