Repeat String - Javascript

Question

What is the best or most concise method for returning a string repeated an arbitrary amount of times?

The following is my best shot so far:

function          


        

Answer 1

Expanding P.Bailey's solution:

String.prototype.repeat = function(num) {
    return new Array(isNaN(num)? 1 : ++num).join(this);
    }

This way you should be safe from unexpected argument types:

var foo = 'bar';
alert(foo.repeat(3));              // Will work, "barbarbar"
alert(foo.repeat('3'));            // Same as above
alert(foo.repeat(true));           // Same as foo.repeat(1)

alert(foo.repeat(0));              // This and all the following return an empty
alert(foo.repeat(false));          // string while not causing an exception
alert(foo.repeat(null));
alert(foo.repeat(undefined));
alert(foo.repeat({}));             // Object
alert(foo.repeat(function () {})); // Function

EDIT: Credits to jerone for his elegant ++num idea!