Lean.Compiler.LCNF.LetDecl Lean.Compiler.LCNF.Purity.pure →
  Lean.Compiler.LCNF.Code Lean.Compiler.LCNF.Purity.pure →
    Lean.Name →
      ℕ →
        Array (Lean.Compiler.LCNF.Arg Lean.Compiler.LCNF.Purity.impure) →
          Lean.Compiler.LCNF.ToImpureM✝ (Lean.Compiler.LCNF.Code Lean.Compiler.LCNF.Purity.impure)