JS will immediately error on the lack of parens, but the `in` vs `of` iterates over indexes, not values, and those indexes are unfortunately converted to strings (since `for-in` is object field-name iteration). So even TypeScript would not have caught it when the (stringified) index is used as the first argument of `fs.watch()`.
`for path in paths`
should be
`for (const path of paths)`
JS will immediately error on the lack of parens, but the `in` vs `of` iterates over indexes, not values, and those indexes are unfortunately converted to strings (since `for-in` is object field-name iteration). So even TypeScript would not have caught it when the (stringified) index is used as the first argument of `fs.watch()`.