{-| This is a flexible SPDX license type, which can be used for recursive
    compound-expressions, or for hpack-dhall, when specialized to `Text`.

- `NOASSERTION` is the identity in all conjunctions.
- `NONE` is the annihilator in `and` and treated as a weaker identity in `or`.
- `Expression` is any other arbitrary compound-expression.
-}
λ(compound-expression : Type) →
  < NOASSERTION | NONE | Expression : compound-expression >