{motive : Lean.Meta.Match.Alt → Sort u} →
  ((ref : Lean.Syntax) →
      (idx : ℕ) →
        (rhs : Lean.Expr) →
          (fvarDecls : List Lean.LocalDecl) →
            (patterns : List Lean.Meta.Match.Pattern) →
              (cnstrs : List (Lean.Expr × Lean.Expr)) →
                (notAltIdxs : Array ℕ) →
                  motive
                    { ref := ref, idx := idx, rhs := rhs, fvarDecls := fvarDecls, patterns := patterns,
                      cnstrs := cnstrs, notAltIdxs := notAltIdxs }) →
    (t : Lean.Meta.Match.Alt) → motive t