sprintf

sprintf.js

var sprintf = function (str) {
    var args = Array.prototype.slice.call(arguments, 1),
        hash = {
            '%s': String,
            '%d': parseInt,
            '%f': parseFloat
        };
    return str.replace(/%0(\d+)d/g, function (m, num) {
        var r = String(args.shift()),
            c = '';
        num = parseInt(num, 10) - r.length;
        while ((num -= 1) >= 0) {
            c += '0';
        }
        return c + r;
    }).replace(/%[sdf]/g, function (m) {
        return hash[m](args.shift());
    });
};