literal

Exactly one specific value: a string, a number or true/false. Strict comparison (===).

Signature

function literal<const T extends string | number | boolean>(value: T, msg?: Message): Schema<T>

Parameter	Type	Description
`value`	`string	number
`msg`	`Message`	Custom message. Replaces the default messages for all errors of this schema

Code	When	Default message
`required`	The value is empty	Required
`literal`	The value does not match	Must be {expected}

You can change the texts: see Messages & i18n.

The result type is the literal itself: literal('admin') gives 'admin', not string.
literal('') won't work: an empty string is a missing value. See Empty values.

const Signup = object({
  terms: literal(true, 'You must accept the terms'),
});

const Payload = object({ version: literal(2), data: unknown() });