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  1. deriveTypeElim :: Name -> Q [Dec]

    eliminators Data.Eliminator.TH

    deriveTypeElim dataName generates a type-level eliminator for the datatype dataName. The eliminator will follow these naming conventions:

    • If the datatype has an alphanumeric name, its eliminator will have that name with Elim prepended.
    • If the datatype has a symbolic name, its eliminator will have that name with ~> prepended.

  2. deriveTypeElimNamed :: String -> Name -> Q [Dec]

    eliminators Data.Eliminator.TH

    deriveTypeElimNamed funName dataName generates a type-level eliminator named funName for the datatype dataName.

  3. deriveClasses :: OptionsT (f :: Type -> Type) -> [Name]

    enum-subset-generate Data.MakeEnum.Options

    No documentation available.

  4. deriveGeneralizable :: Name -> DecsQ

    extrapolate Test.Extrapolate

    Derives a Generalizable instance for a given type Name. If needed, this function also automatically derivates Listable, Express and Name instances using respectively deriveListable, deriveExpress and deriveName. Consider the following Stack datatype: 

    data Stack a = Stack a (Stack a) | Empty
    Writing 
    deriveGeneralizable ''Stack
    will automatically derive the following Generalizable instance: 
    instance Generalizable a => Generalizable (Stack a) where
instances s = this "s" s
$ let Stack x y = Stack undefined undefined `asTypeOf` s
in instances x
. instances y
    This function needs the TemplateHaskell extension.

  5. deriveGeneralizableCascading :: Name -> DecsQ

    extrapolate Test.Extrapolate

    Derives a Generalizable instance for a given type Name cascading derivation of type arguments as well.

  6. deriveGeneralizableIfNeeded :: Name -> DecsQ

    extrapolate Test.Extrapolate

    Same as deriveGeneralizable but does not warn when instance already exists (deriveGeneralizable is preferable).

  7. deriveListable :: Name -> DecsQ

    extrapolate Test.Extrapolate

    Derives a Listable instance for a given type Name. Consider the following Stack datatype: 

    data Stack a  =  Stack a (Stack a) | Empty
    Writing 
    deriveListable ''Stack
    will automatically derive the following Listable instance: 
    instance Listable a => Listable (Stack a) where
tiers  =  cons2 Stack \/ cons0 Empty
    Warning: if the values in your type need to follow a data invariant, the derived instance won't respect it. Use this only on "free" datatypes. Needs the TemplateHaskell extension.

  8. deriveListableCascading :: Name -> DecsQ

    extrapolate Test.Extrapolate

    Derives a Listable instance for a given type Name cascading derivation of type arguments as well. Consider the following series of datatypes: 

    data Position  =  CEO | Manager | Programmer

data Person  =  Person
{  name :: String
,  age :: Int
,  position :: Position
}

data Company  =  Company
{  name :: String
,  employees :: [Person]
}
    Writing 
    deriveListableCascading ''Company
    will automatically derive the following three Listable instances: 
    instance Listable Position where
tiers  =  cons0 CEO \/ cons0 Manager \/ cons0 Programmer

instance Listable Person where
tiers  =  cons3 Person

instance Listable Company where
tiers  =  cons2 Company

  9. deriveListable :: Name -> DecsQ

    extrapolate Test.Extrapolate.Core

    Derives a Listable instance for a given type Name. Consider the following Stack datatype: 

    data Stack a  =  Stack a (Stack a) | Empty
    Writing 
    deriveListable ''Stack
    will automatically derive the following Listable instance: 
    instance Listable a => Listable (Stack a) where
tiers  =  cons2 Stack \/ cons0 Empty
    Warning: if the values in your type need to follow a data invariant, the derived instance won't respect it. Use this only on "free" datatypes. Needs the TemplateHaskell extension.

  10. deriveListableCascading :: Name -> DecsQ

    extrapolate Test.Extrapolate.Core

    Derives a Listable instance for a given type Name cascading derivation of type arguments as well. Consider the following series of datatypes: 

    data Position  =  CEO | Manager | Programmer

data Person  =  Person
{  name :: String
,  age :: Int
,  position :: Position
}

data Company  =  Company
{  name :: String
,  employees :: [Person]
}
    Writing 
    deriveListableCascading ''Company
    will automatically derive the following three Listable instances: 
    instance Listable Position where
tiers  =  cons0 CEO \/ cons0 Manager \/ cons0 Programmer

instance Listable Person where
tiers  =  cons3 Person

instance Listable Company where
tiers  =  cons2 Company

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