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https://github.com/bendtherules/eslint-plugin-undef-init.git
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49 lines
1.2 KiB
Markdown
49 lines
1.2 KiB
Markdown
# Always initialize variables during declaration. Set it explicitly to undefined, if required. (undef-init)
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### It is better to explicitly initialize all variable declarations.
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Instead of naked var / let declarations (which are implicitly set to `undefined` anyway), always explicitly set them to `undefined`. It makes clear that you explicitly intended to set them to undefined, not just because you forgot to initialize.
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## Rule Details
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This rule aims to...
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Examples of **incorrect** code for this rule:
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```js
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var a;
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let b;
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let c, d;
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let d, e = 1;
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for (var f of {}){var g;}
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for (var i in []){var j;}
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```
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Examples of **correct** code for this rule:
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```js
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var a = undefined;
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let b = undefined;
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let b1 = b;
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let c = undefined, d = undefined;
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for (var f of {}){var g = undefined;}
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for (var i in []){do_something()}
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```
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### Options
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There are no options
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## When Not To Use It
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If you feel setting vraiables implicitly to `undefined` is better than setting them explicitly, then don't use this - use `no-undef-init`.
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## More
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Ideally this would be a configuration in the in-built eslint rule `no-undef-init` instead of a separate rule, but wasn't accepted by maintainers. Hence, it's an external plugin. |