How to create a string with n characters? How to create a string with specific length? [duplicate]

Answer 1

Array.prototype.join doesn't have to be called on an Array, just an Object with a length property (tested in Google Chrome, FireFox, IE10)

function makeStr(len, char) {
    return Array.prototype.join.call({length: (len || -1) + 1}, char || 'x');
}
makeStr(5); // "xxxxx"

This lets you benefit from native function making the string, without the overhead of a huge array.