-- Note: This actually faster than:
    --      null (UUID 0 0 0 0) = True
    --      null _              = False

-- |The nil UUID, as defined in RFC 4122.
-- It is a UUID of all zeros. @'null' u@ iff @'u' == 'nil'@.
nil :: UUID
nil = UUID 0 0 0 0
nil :: UUID
nil = UUID 0 0 0 0
nil = UUID 0 0 0 0