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1. deriveRepresentable0 :: Name -> Q [Dec]

   generic-deriving	Generics.Deriving.TH

   Given the type and the name (as string) for the Representable0 type synonym to derive, generate the Representable0 instance.

2. deriveRepresentable0Options :: Options -> Name -> Q [Dec]

   generic-deriving	Generics.Deriving.TH

   Like deriveRepresentable0, but takes an Options argument.

3. deriveRepresentable1 :: Name -> Q [Dec]

   generic-deriving	Generics.Deriving.TH

   Given the type and the name (as string) for the Representable1 type synonym to derive, generate the Representable1 instance.

4. deriveRepresentable1Options :: Options -> Name -> Q [Dec]

   generic-deriving	Generics.Deriving.TH

   Like deriveRepresentable1, but takes an Options argument.

5. deriveSelectors :: Name -> Q [Dec]

   generic-deriving	Generics.Deriving.TH

   Given a datatype name, derive datatypes and instances of class Selector. On GHC 7.11 and up, this functionality is no longer used in GHC generics, so this function generates no declarations.

6. deriveLift :: Name -> Q [Dec]

   th-lift	Language.Haskell.TH.Lift

   No documentation available.

7. deriveLift' :: [Role] -> Info -> Q [Dec]

   th-lift	Language.Haskell.TH.Lift

   Obtain Info values through a custom reification function. This is useful when generating instances for datatypes that have not yet been declared.

8. deriveLiftMany :: [Name] -> Q [Dec]

   th-lift	Language.Haskell.TH.Lift

   Derive Lift instances for many datatypes.

9. deriveLiftMany' :: [([Role], Info)] -> Q [Dec]

   th-lift	Language.Haskell.TH.Lift

   No documentation available.

10. deriveGeneric :: Name -> Q [Dec]

    generics-sop	Generics.SOP.TH

    Generate generics-sop boilerplate for the given datatype. This function takes the name of a datatype and generates:

    • a Code instance
    • a Generic instance
    • a HasDatatypeInfo instance
    Note that the generated code will require the TypeFamilies and DataKinds extensions to be enabled for the module. Example: If you have the datatype

    data Tree = Leaf Int | Node Tree Tree
    

    and say

    deriveGeneric ''Tree
    

    then you get code that is equivalent to:

    instance Generic Tree where
    
    type Code Tree = '[ '[Int], '[Tree, Tree] ]
    
    from (Leaf x)   = SOP (   Z (I x :* Nil))
    from (Node l r) = SOP (S (Z (I l :* I r :* Nil)))
    
    to (SOP    (Z (I x :* Nil)))         = Leaf x
    to (SOP (S (Z (I l :* I r :* Nil)))) = Node l r
    to (SOP (S (S x)))                   = x `seq` error "inaccessible"
    
    instance HasDatatypeInfo Tree where
    type DatatypeInfoOf Tree =
    T.ADT "Main" "Tree"
    '[ T.Constructor "Leaf", T.Constructor "Node" ]
    
    datatypeInfo _ =
    T.demoteDatatypeInfo (Proxy :: Proxy (DatatypeInfoOf Tree))
    

    Limitations: Generation does not work for GADTs, for datatypes that involve existential quantification, for datatypes with unboxed fields.

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