NodeList.forEach

[Kalinovych]

Hi Richard,
how about to add forEach() method to the NodeList?

public function forEach( callback : Function ) : void
{
    for( var node : Node = head; node; node = node.next )
    {
        callback( node );
    }
}

simple example of use in a System:

override public function addToEngine( engine:Engine ):void
{
    nodeList = engine.getNodeList( MyNode );
    nodeList.forEach( handleNodeAdded );
    nodeList.nodeAdded.add( handleNodeAdded );
    nodeList.nodeRemoved.add( handleNodeRemoved );
}

override public function removeFromEngine( engine:Engine ):void
{
    nodeList.nodeAdded.remove( handleNodeAdded );
    nodeList.nodeRemoved.remove( handleNodeRemoved );
    nodeList.forEach( handleNodeRemoved );
    nodeList = null;
}

Maybe somebody will like it to use in the update function.
Of course for() iteration will be a bit faster than forEach() but we can live this decision to a developer.

override public function update( time:Number ):void
{
    nodeList.forEach( processNode );
}

private function processNode( node:MyNode ):void
{

}

Sometimes we need to pass additional params like a "time" in the update func.
Here is the extended implementation:

public function forEach( callback : Function, ...params ) : void
{
    if ( head )
    {
        params.unshift( null );
        for( var node : Node = head; node; node = node.next )
        {
            params[0] = node;
            callback.apply( null, params );
        }
    }
}

Now update function can look like:

override public function update( time:Number ):void
{
    nodeList.forEach( processNode, time );

    // nodeList.forEach( processNode ); - will work fine too
}

private function processNode( node:MyNode, time:Number ):void
{

}

Also can be an implementation with checking a value returned by callback.apply( null, params ); and if this value == false break forEach loop :)