[Request] Utility for creating unions from object keys

[pheuter]

Request a feature

(Discord thread for context)

Our codebase has large collections of objects that represent enum values mapping keys of concrete types (like QualificationType in my example below, which is a Prisma enum in our db) to string values that are rendered as labels in the UI, such as in select dropdowns.

It would be super helpful and valuable to have a way in arktype to convert these objects to string unions comprised of the enumerable keys in that object, accomplishing something similar to the arkEnumValidator helper function I created below:

export const arkEnumValidator = <K extends string, V>(obj: Record<K, V>) => {
	return type(
		Object.keys(obj)
			.map((t) => `'${t}'`)
			.join('|') as Infer<K>
	);
};

///

export const qualificationTypeOptions = {
    drivers: "Driver's License",
    cna: 'CNA Certification',
    lpn: 'LPN License',
    rn: 'RN License',
    hha: 'HHA Certificate',
    caregiver_cert: 'Caregiver Certificate',
    first_aid: 'First Aid Certification',
    cpr: 'CPR Certification',
    food_handler_card: 'Food Handler Card',
    custom: 'Custom'
} as const satisfies { [P in QualificationType]: string };

///

export const formSchema = type({
	qualificationType: arkEnumValidator(qualificationTypeOptions)
});