a super simple JSON stringify

gistfile1.txt

function repeat(_char, num) {
  return (new Array(num + 1)).join(_char);
}

function stringify(object, blanks) {
  blanks = blanks || 4;
  var leading = repeat(' ', blanks);
  switch (true) {
  case Array.isArray(object):
    return "[" + object.map(function(item) {return stringify(item, blanks + 4)}).join(', ') + "]";
  break;
  case (typeof object == "object"):
  return "{\n" + Object.keys(object).map(function(key) {
      return leading + '"' + key + '": '  + stringify(object[key], blanks + 4);
    }).join(',\n') + "\n" + repeat(' ', blanks - 4) + "}";
  break;
  case (typeof object == 'string'):
    return '"' + object + '"';
  default:
    return object + "";
  }
}
console.log(stringify(
  {
    name: 'jack',
    age: 18,
    profile: {
      city: 'beijing',
      phone_number: 18911456678,
      person: ['mary', 'ford', 'peak', {hello: 'james'}]
    }
  }
));