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correctness.language

for-in over array-like value

Prefer for-of or index loops instead of for-in on arrays.

#Metadata

Rule ID
ts.correctness.for-in-on-array
Severity
medium
Confidence
0.85
Languages
javascript, typescript
Presets
recommended, strict
Stability
stable
Applies to
file
Tags
correctness, crq-cor-037, language, rules-catalog

#Why it matters

for-in enumerates keys (often as strings) and may include inherited properties; for-of iterates values safely.

#Remediation

Use `for (const item of array)` or indexed iteration instead of for-in.

#Repository path

The generated metadata points to critiq-rules/libs/rules/catalog/rules/typescript/ts.correctness.for-in-on-array.rule.yaml.