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arrayFinds

Reports using .filter()[0] instead of .find() when looking for a single element.

✅ This rule is included in the ts stylistic and stylisticStrict presets.

When searching for the first item in an array matching a condition, using .filter(...)[0] is less efficient than using .find(...). The .find() method stops searching after finding the first match, whereas .filter() iterates through the entire array.

Examples

Section titled “Examples”
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Options

Section titled “Options”

This rule is not configurable.

When Not To Use It

Section titled “When Not To Use It”

If you intentionally use .filter(...)[0] to execute side effects in the callback on all array elements before returning the first match, you may want to disable this rule. However, this pattern is unusual and may indicate a need for code refactoring.

Further Reading

Section titled “Further Reading”

Equivalents in Other Linters

Section titled “Equivalents in Other Linters”