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unicorn/prefer-array-flat-map Style

🛠️ An auto-fix is available for this rule.

What it does

Prefers the use of .flatMap() when map().flat() are used together.

Why is this bad?

It is slightly more efficient to use .flatMap(…) instead of .map(…).flat().

Examples

Examples of incorrect code for this rule:

javascript
const bar = [1, 2, 3].map(i => [i]).flat();

Examples of correct code for this rule:

javascript
const bar = [1, 2, 3].flatMap(i => [i]);

How to use

To enable this rule in the CLI or using the config file, you can use:

bash
oxlint --deny unicorn/prefer-array-flat-map
json
{
  "rules": {
    "unicorn/prefer-array-flat-map": "error"
  }
}

References

Released under the MIT License.