$.to-primitive.js 645 B

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  1. // 7.1.1 ToPrimitive(input [, PreferredType])
  2. var isObject = require('./$.is-object');
  3. // instead of the ES6 spec version, we didn't implement @@toPrimitive case
  4. // and the second argument - flag - preferred type is a string
  5. module.exports = function(it, S){
  6. if(!isObject(it))return it;
  7. var fn, val;
  8. if(S && typeof (fn = it.toString) == 'function' && !isObject(val = fn.call(it)))return val;
  9. if(typeof (fn = it.valueOf) == 'function' && !isObject(val = fn.call(it)))return val;
  10. if(!S && typeof (fn = it.toString) == 'function' && !isObject(val = fn.call(it)))return val;
  11. throw TypeError("Can't convert object to primitive value");
  12. };