generator-star

Enforces consistent spacing around the asterisk in generator functions.

Generators are a new type of function in ECMAScript 6 that can return multiple values over time. These special functions are indicated by placing an * after the function keyword.

Here is an example of a generator function:

/*eslint-env es6*/

function* generator() {
    yield "44";
    yield "55";
}
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This is also valid:

/*eslint-env es6*/

function *generator() {
    yield "44";
    yield "55";
}
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This is valid as well:

/*eslint-env es6*/

function * generator() {
    yield "44";
    yield "55";
}
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To keep a sense of consistency when using generators this rule enforces a single position for the *.

Rule Details

This rule enforces that the * is either placed next to the function keyword or the name of the function. The single option for this rule is a string specifying the placement of the asterisk. For this option you may pass "start", "middle" or "end". The default is "end".

You can set the style in configuration like this:

"generator-star": ["error", "start"]
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When using "start" this placement will be enforced:

/*eslint-env es6*/

function* generator() {
}
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When using "middle" this placement will be enforced:

/*eslint-env es6*/

function * generator() {
}
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When using "end" this placement will be enforced:

/*eslint-env es6*/

function *generator() {
}
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When using the expression syntax "start" will be enforced here:

/*eslint-env es6*/

var generator = function* () {
}
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When using the expression syntax "middle" will be enforced here:

/*eslint-env es6*/

var generator = function * () {
}
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When using the expression syntax "end" will be enforced here:

/*eslint-env es6*/

var generator = function *() {
}
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When using the expression syntax this is valid for both "start" and "end":

/*eslint-env es6*/

var generator = function*() {
}
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The shortened object literal syntax for generators is not affected by this rule.

When Not To Use It

If your project will not be using generators you do not need this rule.

Version

This rule was introduced in ESLint v0.12.0 and removed in v1.0.0-rc-1.