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Function: oneOf()

oneOf<T>(allowed, errorMessage?): Validator<T, T, string>

Defined in: validation/validators/index.ts:397

Validates value is one of the allowed values.

Type Parameters​

T​

T

Parameters​

allowed​

readonly T[]

Array of allowed values

errorMessage?​

string

Custom error message (optional)

Returns​

Validator<T, T, string>

Validator that checks value is in allowed list

Example​

oneOf(['admin', 'user', 'guest'])('admin') // => Valid('admin')
oneOf(['admin', 'user', 'guest'])('superadmin') // => Invalid(['Must be one of: admin, user, guest'])

// With custom error
oneOf([1, 2, 3], 'Invalid option')(2) // => Valid(2)
oneOf([1, 2, 3], 'Invalid option')(4) // => Invalid(['Invalid option'])