disallow octal literals (no-octal)

The "extends": "eslint:recommended" property in a configuration file enables this rule.

Octal literals are numerals that begin with a leading zero, such as:

var num = 071;      // 57

Because the leading zero which identifies an octal literal has been a source of confusion and error in JavaScript code, ECMAScript 5 deprecates the use of octal numeric literals.

Rule Details

The rule disallows octal literals.

If ESLint parses code in strict mode, the parser (instead of this rule) reports the error.

Examples of incorrect code for this rule:

/*eslint no-octal: "error"*/

var num = 071;
var result = 5 + 07;

Examples of correct code for this rule:

/*eslint no-octal: "error"*/

var num  = "071";


  • JSHint: W115


This rule was introduced in ESLint 0.0.6.


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