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func-style ignores function expressions not starting with var keyword

See original GitHub issue

The func-style rule has been set to enforce use of function declarations.

var eslintConfig = {
	'root': true,
	'env': {
		'browser': true
	'extends': 'eslint:recommended',
	'rules': {
		/** Coding Style Standards **/
		'func-style': ['error', 'declaration', { 'allowArrowFunctions': true }]

module.exports = eslintConfig;

I would expect that with this configuration, code such as the one below would lead to an error. But it doesn’t.

var fnVariable;

fnVariable = function() {
      return true;

Issue Analytics

  • State:closed
  • Created 7 years ago
  • Reactions:1
  • Comments:25 (13 by maintainers)

github_iconTop GitHub Comments

kiranjhollacommented, Jan 19, 2017

That code could also be written by declaring the function separately and then assigning it to the variable foo as and when required.

let foo = 5

assert.equal(foo + 5, 10);

foo = _myFunction;

 * JSDoc what the function is meant to do.
function _myFunction() {
         // Do what it is meant to do...

My idea is to enforce a consistent coding style across many developers so that code is easily recognizable for the entire team. After this discussion, I realize that func-style disallowing all Function Expressions might be overkill. However, I do believe func-style should include an option to disallow assignment of function expressions to variables.

albertocommented, Mar 11, 2017

Thanks for your interest in improving eslint. Unfortunately, it looks like this issue didn’t get enough support from the team and so I’m closing it. While we wish we’d be able to accommodate everyone’s requests, we do need to prioritize. We’ve found that issues failing to reach consensus after 21 days tend to never do it, and as such, we close those issues. This doesn’t mean the idea isn’t interesting, just that it’s not something the team can commit to.

Read more comments on GitHub >

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