Haskus.Utils.Types.Generics

Generics

Documentation

module GHC.Generics

Fields

data Field (name :: Symbol) (t :: *)

Named field

type family FieldType f where ...

Equations

FieldType (Field name t) = t

type family LookupField (fs :: [*]) (s :: Symbol) where ...

Equations

LookupField (Field name t ': fs) name = Field name t

LookupField (Field name t ': fs) s = LookupField fs s

LookupField '[] name = TypeError (Text "Cannot find field with name: " :<>: ShowType name)

type family LookupFieldType fs s where ...

Equations

LookupFieldType fs s = FieldType (LookupField fs s)

Data type fields

type family ExtractFields (a :: *) where ...

Extract fields of a data type: - require selector symbols - only support data type with a single constructor

Equations

ExtractFields a = ExtractFields' (Rep a)

type family ExtractFieldTypes (a :: *) where ...

Extract types of the fields of a data type - only support data type with a single constructor

Equations

ExtractFieldTypes a = ExtractFieldTypes' (Rep a)