Function values are accepted only when they declare no formal parameters, in which case they are treated as
factories for the underlying value and the type guard is not invoked. Non-function values are validated by the type
guard when provided, or accepted unconditionally otherwise.
Checks if a value is a Lazy reference.
Function values are accepted only when they declare no formal parameters, in which case they are treated as factories for the underlying value and the type guard is not invoked. Non-function values are validated by the type guard when provided, or accepted unconditionally otherwise.