Accept number in string type

Hello! I'm parsing each value in a form with

JSON.parse

JSON.parse

to convert string values like

false

false

to actual booleans. Unfortunately, this introduces the issue, that if someone inputs

into a text field, it gets parsed into a number type by

JSON.parse

JSON.parse

. Then if the field is type

string

string

. An error is thrown, since number is not assignable to string.

How should a type look like, if it should handle such a situation?