Problem with mixing constructors defined via pattern-matching with external parameters

[sxhya]

\func f {X : \Type} => X \where {
  \data D1 (n : Nat) \with
    | 0 => nilD X -- 'X' is not a reference to either a definition or a variable
}



\func f2 {X : \Type} => X \where {
  \data D2 (n : Nat)
    | nilD2 X -- No error
}