useFieldArray: Why typescript doesn't support an array of primitive values, e.g array of strings?

[lucashfreitas]

The issue

Using useFieldArray with array of primitive values, e.g array of strings, will cause an type error on react hook form.

This is a wide issue and was reported multiple other times, as seem:

• https://www.reddit.com/r/typescript/comments/1cw0nvw/reacthookforms_usefieldarray_type_string_is_not/
• What type to use? useFieldArray #1986
• https://github.com/orgs/react-hook-form/discussions/7586

Why?

Quite often we just need an array of string and not an array of objects. In fact if i "HACK" the type-system the form work flawless, as seem below. There is any particular reason why react hook form does not support primitive values on useFieldArray out of the box?

  const { append, remove } = useFieldArray<{
    locations: { locations: string }[]
  }>({
    control: form.control as any,
    name: "locations",
  })