# E0258: missing type between '|' and '|' (or '&' and '&')

An extra `|` or `&` is allowed at the beginning of a TypeScript type. However, it is a syntax error to write an extra `|` or `&` in the middle of a TypeScript type:

    type Primitive =
      | string
      | number
      | bigint
      | boolean
      | null |
      | undefined

To fix this error, remove the extra `|` or `&`:

    type Primitive =
      | string
      | number
      | bigint
      | boolean
      | null
      | undefined

Introduced in quick-lint-js version 2.7.0.

Documentation for other errors