open list

meta_definition e := environment.mk_std 0

vm_eval environment.trust_lvl e
vm_eval environment.is_std e

vm_eval (environment.add e (declaration.def "foo" []
                                           (expr.sort (level.succ (level.zero)))
                                           (expr.sort (level.succ (level.zero)))
                                           bool.tt) : exceptional environment)

meta_definition e1 := (environment.add e (declaration.def "foo" []
                                            (expr.sort (level.succ (level.zero)))
                                            (expr.sort level.zero)
                                            bool.tt) : exceptional environment)

print "-----------"
open name

vm_eval do
   e₁ ← environment.add e (declaration.def "foo" []
                                           (expr.sort (level.succ (level.zero)))
                                           (expr.sort level.zero)
                                           bool.tt),
   e₂ ← environment.add_inductive e₁ "Two" [] 0 (expr.sort (level.succ level.zero))
                                  [("Zero", expr.const "Two" []),
                                   ("One",  expr.const "Two" [])],
   d₁ ← environment.get e₂ "Zero",
   d₂ ← environment.get e₂ "foo",
   /- TODO(leo): use

        return (declaration.type d)

      We currently don't use 'return' because the type is too high-order.

        return : ∀ {m : Type → Type} [monad m] {A : Type}, A → m A
      It is the kind of example where we should fallback to first-order unification for
      inferring the (m : Type → Type)

      The new elaborator should be able to handle it.
   -/
   exceptional.success (declaration.type d₁, declaration.type d₂,
                        environment.is_recursor e₂ ("Two" <.> "rec"),
                        environment.constructors_of e₂ "Two",
                        environment.fold e₂ (to_format "") (λ d r, r + format.line + to_fmt (declaration.to_name d)))