var Q = function(funcs, callback){
    var returnCount = 0;
    if( typeof(funcs) == "function" ) funcs = [funcs];
    var totalCount = funcs.length;
    var values = [];
 
    var createCallback = function(i){
        return function(result){
            values[i] = result;
            returnCount++;
            if( returnCount == totalCount ){
                callback(values);
            }
        }
    }
 
    for(var i=0;i<totalCount;i++){
        // How to keep the scope?
        funcs[i](createCallback(i));
    }
}
 
function A(o){
    this.v = o || 10;
}
 
A.prototype.test = function(cb){ cb(this.v); }
 
var a = new A();
var b = new A(20);
 
Q([a.test, b.test], function(results){ 
    print(results[0]);
    print(results[1]);
});

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