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Is it possible to define a generic type Vector in Actionsctipt 3?

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遇见更好的自我
遇见更好的自我 2021-02-08 22:04

Hi i need to make a VectorIterator, so i need to accept a Vector with any type. I am currently trying to define the type as * like so:

var collection:Vector.<
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  • 小鲜肉
    小鲜肉 (楼主)
    2021-02-08 22:50

    So it looks like the answer is there is no way to implicitly cast a Vector of a type to valid super type. It must be performed explicitly with the global Vector.<> function.

    So my actual problem was a mix of problems :)

    It is correct to use Vector. as a generic reference to another Vector, but, it cannot be performed like this:

    var spriteList:Vector. = new Vector.()
var genericList:Vector. = new Vector.()
genericList = spriteList // this will cause a type casting error



    The assignment should be performed using the global Vector() function/cast like so:
    


    var spriteList:Vector. = new Vector.()
var genericList:Vector. = new Vector.()
genericList = Vector.(spriteList)



    It was a simple case of me not reading the documentation.
    


    Below is some test code, I would expect the Vector. to cast implicitly to Vector.<*>.
    


    public class VectorTest extends Sprite
{
    public function VectorTest()
    {
        // works, due to <*> being strictly the same type as the collection in VectorContainer
        var collection:Vector.<*> = new Vector.() 

        // compiler complains about implicit conversion of  to <*>
        var collection:Vector. = new Vector.()
        collection.push("One")
        collection.push("Two")
        collection.push("Three")

        for each (var eachNumber:String in collection)
        {
            trace("eachNumber: " + eachNumber)
        }

        var vectorContainer:VectorContainer = new VectorContainer(collection)

        while(vectorContainer.hasNext())
        {
            trace(vectorContainer.next) 
        }
    }
}

public class VectorContainer
{
    private var _collection:Vector.<*>

    private var _index:int = 0

    public function VectorContainer(collection:Vector.<*>)
    {
        _collection = collection
    }

    public function hasNext():Boolean
    {
        return _index < _collection.length
    }

    public function get next():*
    {
        return _collection[_index++]
    }
}

    
    
    
             
    
                                                        
    
            
            
    
              
                
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