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