eslint/docs/src/rules/no-new-symbol.md

   1 ---
   2 title: no-new-symbol
   3 layout: doc
   4 rule_type: problem
   5 further_reading:
   6 - https://www.ecma-international.org/ecma-262/6.0/#sec-symbol-objects
   7 ---
   8
   9
  10
  11 `Symbol` is not intended to be used with the `new` operator, but to be called as a function.
  12
  13 ```js
  14 var foo = new Symbol("foo");
  15 ```
  16
  17 This throws a `TypeError` exception.
  18
  19 ## Rule Details
  20
  21 This rule is aimed at preventing the accidental calling of `Symbol` with the `new` operator.
  22
  23 ## Examples
  24
  25 Examples of **incorrect** code for this rule:
  26
  27 ::: incorrect
  28
  29 ```js
  30 /*eslint no-new-symbol: "error"*/
  31 /*eslint-env es6*/
  32
  33 var foo = new Symbol('foo');
  34 ```
  35
  36 :::
  37
  38 Examples of **correct** code for this rule:
  39
  40 ::: correct
  41
  42 ```js
  43 /*eslint no-new-symbol: "error"*/
  44 /*eslint-env es6*/
  45
  46 var foo = Symbol('foo');
  47
  48 // Ignores shadowed Symbol.
  49 function bar(Symbol) {
  50     const baz = new Symbol("baz");
  51 }
  52
  53 ```
  54
  55 :::
  56
  57 ## When Not To Use It
  58
  59 This rule should not be used in ES3/5 environments.