code: function format(str, ...args) {
    return !args.length ? str : str.replace(/%[a-zA-Z]/, (match) => args.shift() || match);
  }
docs: returns a checker function which runs all validator functions in the validators array enable string formatting like in console log, ie console.log('I like to %s a lot', 'poop') > "I like to poop alot"