[[ts] Check if obj is instanceof U] Check if obj is instanceof U

new_gist_file

// => http://stackoverflow.com/questions/17392349/how-can-i-check-if-element-is-an-instanceof-u

function OfType<T, U>(list: T[], arg: Function) : U[]
{
    var result: U[] = [];

    list.forEach(e => {
        // extract the name of the class
        // used to match primitive types
        var typeName = /function\s*([^(]*)/i.exec(arg+"")[1].toLocaleLowerCase();

        var isOfType = typeof(e) === typeName;

        // if it is not primitive or didn't match the type
        // try to check if it is an instanceof
        if (!isOfType)
        {
            try {
                isOfType = (e instanceof arg)
            }
            catch (ex) { }
        }

        if (isOfType)
            result.push(<U><any>e);
    });

    return <any[]>result;
}

var list: any[] = [];
list.push("A");
list.push(2);

var numbers = OfType<any, number>(list, Number);


alert("Numbers: " + numbers);