λ(nix : ../NixPrelude.dhall) →
  let Number = ./Type.dhall

  let Number/fromNatural = ./fromNatural.dhall nix

  let Number/lessThan = ./lessThan.dhall nix

  let zero = Number/fromNatural 0

  in  λ(a : Number) → if Number/lessThan a zero then zero else a