docs: function Formi(func) {
    var offset = func !== undefined && typeof func !== 'function' ? 0 : 1;
  
    // default to Identity if no function is defined
    if (func === undefined || typeof func !== 'function') {
      func = Formi.identity;
    }
  
    // return function & argument result
    var result = func.apply(undefined, normalize(arguments, offset));
  
    // slice result
    if (result && result.length && !(typeof result === 'string' || result instanceof String)) {
      return slice(result);
    }
  
    return result;
  }