var isObject = require('../internals/is-object');

// `OrdinaryToPrimitive` abstract operation
// https://tc39.es/ecma262/#sec-ordinarytoprimitive
module.exports = function (input, pref) {
  var fn, val;
  if (pref === 'string' && typeof (fn = input.toString) == 'function' && !isObject(val = fn.call(input))) return val;
  if (typeof (fn = input.valueOf) == 'function' && !isObject(val = fn.call(input))) return val;
  if (pref !== 'string' && typeof (fn = input.toString) == 'function' && !isObject(val = fn.call(input))) return val;
  throw TypeError("Can't convert object to primitive value");
};