ExtractRequiredKeys
See source codetype ExtractRequiredKeys<T extends object> = {
[K in keyof T]: undefined extends T[K] ? never : K
}[keyof T]Prev
ExtractOptionalKeysNext
UnionValidatorConfigtype ExtractRequiredKeys<T extends object> = {
[K in keyof T]: undefined extends T[K] ? never : K
}[keyof T]