    {-|
        Derives an instance of @Monoid@. It uses the product
        construction of monoids. @mappend@ on two different constructors
        is undefined.
    -}
    module Data.Derive.Monoid(makeMonoid) where
    {-
    import Data.Monoid hiding (First)

    example :: Sample
    instance Monoid a => Monoid (Sample a) where
        mempty = head [First, Second (const mempty 1) (const mempty 2), Third (const mempty 1)]
        mappend (First) (First) = First
        mappend (Second x1 x2) (Second y1 y2) = Second (mappend x1 y1) (mappend x2 y2)
        mappend (Third x1) (Third y1) = Third (mappend x1 y1)
        mappend _ _ | length [First{},Second{},Third{}] > 1 = error "Monoid.mappend: Different constructors for Sample"

    -}
    -- GENERATED START

    import Data.Derive.DSL.DSL
    import Data.Derive.Internal.Derivation

    makeMonoid :: Derivation
    makeMonoid = derivationDSL "Monoid" dslMonoid

    dslMonoid =
        List [Instance ["Monoid"] "Monoid" (List [App "InsDecl" (List [App
        "PatBind" (List [App "PVar" (List [App "Ident" (List [String
        "mempty"])]),App "Nothing" (List []),App "UnGuardedRhs" (List [App
        "App" (List [App "Var" (List [App "UnQual" (List [App "Ident" (
        List [String "head"])])]),App "List" (List [MapCtor (Application (
        Concat (List [List [App "Con" (List [App "UnQual" (List [App
        "Ident" (List [CtorName])])])],MapField (App "Paren" (List [
        Application (List [App "Var" (List [App "UnQual" (List [App
        "Ident" (List [String "const"])])]),App "Var" (List [App "UnQual"
        (List [App "Ident" (List [String "mempty"])])]),App "Lit" (List [
        App "Int" (List [FieldIndex])])])]))])))])])]),App "BDecls" (List
        [List []])])]),App "InsDecl" (List [App "FunBind" (List [Concat (
        List [MapCtor (App "Match" (List [App "Ident" (List [String
        "mappend"]),List [App "PParen" (List [App "PApp" (List [App
        "UnQual" (List [App "Ident" (List [CtorName])]),MapField (App
        "PVar" (List [App "Ident" (List [Concat (List [String "x",ShowInt
        FieldIndex])])]))])]),App "PParen" (List [App "PApp" (List [App
        "UnQual" (List [App "Ident" (List [CtorName])]),MapField (App
        "PVar" (List [App "Ident" (List [Concat (List [String "y",ShowInt
        FieldIndex])])]))])])],App "Nothing" (List []),App "UnGuardedRhs"
        (List [Application (Concat (List [List [App "Con" (List [App
        "UnQual" (List [App "Ident" (List [CtorName])])])],MapField (App
        "Paren" (List [Application (List [App "Var" (List [App "UnQual" (
        List [App "Ident" (List [String "mappend"])])]),App "Var" (List [
        App "UnQual" (List [App "Ident" (List [Concat (List [String "x",
        ShowInt FieldIndex])])])]),App "Var" (List [App "UnQual" (List [
        App "Ident" (List [Concat (List [String "y",ShowInt FieldIndex])])
        ])])])]))]))]),App "BDecls" (List [List []])])),List [App "Match"
        (List [App "Ident" (List [String "mappend"]),List [App "PWildCard"
        (List []),App "PWildCard" (List [])],App "Nothing" (List []),App
        "GuardedRhss" (List [List [App "GuardedRhs" (List [List [App
        "Qualifier" (List [App "InfixApp" (List [App "App" (List [App
        "Var" (List [App "UnQual" (List [App "Ident" (List [String
        "length"])])]),App "List" (List [MapCtor (App "RecConstr" (List [
        App "UnQual" (List [App "Ident" (List [CtorName])]),List []]))])])
        ,App "QVarOp" (List [App "UnQual" (List [App "Symbol" (List [
        String ">"])])]),App "Lit" (List [App "Int" (List [Int 1])])])])],
        App "App" (List [App "Var" (List [App "UnQual" (List [App "Ident"
        (List [String "error"])])]),App "Lit" (List [App "String" (List [
        Concat (List [String "Monoid.mappend: Different constructors for "
        ,DataName])])])])])]]),App "BDecls" (List [List []])])]])])])])]
    -- GENERATED STOP