This library is a collection of functional idioms for ActionScript 3 based on Haskell and Coffeescript. Below are a couple example utilities from the library.

String Lambdas:

private function lambdaTest():void {
    var data:Array = [1,2,3,4,5];
    var data1:Array = lambdaMap(data, "+", 3);
    // The result is: 4,5,6,7,8
    trace(data1); 
        
    data1 = lambdaMap(data, "*", 3);
    //lambdaMap *3: 3,6,9,12,15
    trace("lambdaMap *3:", data1);  

        
    data1 = lambdaMap(data, "==", 3);
    //lambdaMap ==3: false,false,true,false,false
    trace("lambdaMap ==3:", data1);  
        
    data1 = lambdaMap([[1,2,3],[1,2]], "+", [4,5]);
    //lambdaMap [[1,2,3],[1,2]] +[4,5]: [[1,2,3,4,5], [1,2,4,5]]
    trace("lambdaMap [[1,2,3],[1,2]] +[4,5]:", "[["+data1[0]+"], ["+ data1[1]+"]"); 
        
    data1 = lambdaFilter(data, "!=", 3); 
    //lambdaFilter !=3: 1,2,4,5
    trace("lambdaFilter !=3:", data1);
        
    data1 = lambdaFilter(data, ">", 3); 
    //lambdaFilter > 3: 4,5
    trace("lambdaFilter > 3:", data1);
        
    data1 = lambdaFilter(data, "<=", 3); 
    //lambdaFilter <= 3: 1,2,3
    trace("lambdaFilter <= 3:", data1);
}

XML Comprehensions:

private function xmlParsing():void {
    var raw:String = "<xml><game>Starcraft</game><game>Diablo</game><game>Warcraft</game></xml>";
    var data:XML = new XML(raw);
        
    var result:Array = xmlMap(data.game, mapXMLData);
    //xmlMap:  Game:Starcraft, Game:Diablo, Game:Warcraft
    trace("xmlMap:", result); 

    // create a TextField for each node and add them to the display
    xmlMap(data.game, mapXMLSprites).forEach(listCall(addChild));
}

// Used to transform an XML element into a constructed String with a prefix     
private function mapXMLData(node:XML, index:int, xml:XMLList):String {
    return " Game:" + node.toString();
}

// Used to transform an XML element into a TextField        
private function mapXMLSprites(node:XML, index:int, xml:XMLList):TextField {
    var field:TextField = new TextField();
    field.text = " Game:" + node.toString();
    field.y += index * field.textHeight;
    return field;
}

For more information and examples: http://www.jadbox.com/2012/02/announcing-as3fp/