Mimer drops part of the solution with module parameter

[Andreas Abel]

open import Agda.Primitive renaming (Set to Type)
open import Agda.Builtin.Nat using (zero; suc) renaming (Nat to ℕ)

data T : ℕ → Type where
  c : ∀{n} → T n → T (suc n)

module _ (A : Set) where

  data D (n : ℕ) : Type where
    foo : T n → D n
    bar : T (suc n) → D n

  test : {n : ℕ} → T n → D n
  test (c t) = {!!}  -- C-c C-a just gives "foo"

Without the module parameter, the solution is foo (c t).