Disallow arrow functions where they could be confused with comparisons (no-confusing-arrow)

Arrow functions (=>) are similar in syntax to some comparison operators (>, <, <=, and >=). This rule warns against using the arrow function syntax in places where it could be confused with a comparison operator. Even if the arguments of the arrow function are wrapped with parens, this rule still warns about it.

Here's an example where the usage of => could be confusing:

// The intent is not clear
var x = a => 1 ? 2 : 3
// Did the author mean this
var x = function (a) { return a >= 1 ? 2 : 3 }
// Or this
var x = a <= 1 ? 2 : 3

Rule Details

The following patterns are considered warnings:

/*eslint no-confusing-arrow: 2*/
/*eslint-env es6*/

var x = a => 1 ? 2 : 3
var x = (a) => 1 ? 2 : 3

The following patterns are not considered warnings:

/*eslint no-confusing-arrow: 2*/
/*eslint-env es6*/

var x = a => { return 1 ? 2 : 3; }
var x = (a) => { return 1 ? 2 : 3; }

Version

This rule was introduced in ESLint 2.0.0-alpha-2.

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