Safe Haskell | Trustworthy |
---|---|
Language | Haskell2010 |
This module gives the definition of the Lift
class.
This is an internal module. Please import Language.Haskell.TH or Language.Haskell.TH.Syntax instead!
Synopsis
- class Lift (t :: TYPE r) where
- dataToQa :: (Quote m, Data a) => (Name -> k) -> (Lit -> m q) -> (k -> [m q] -> m q) -> (forall b. Data b => b -> Maybe (m q)) -> a -> m q
- dataToExpQ :: (Quote m, Data a) => (forall b. Data b => b -> Maybe (m Exp)) -> a -> m Exp
- liftData :: (Quote m, Data a) => a -> m Exp
- dataToPatQ :: (Quote m, Data a) => (forall b. Data b => b -> Maybe (m Pat)) -> a -> m Pat
- liftString :: Quote m => String -> m Exp
- trueName :: Name
- falseName :: Name
- nothingName :: Name
- justName :: Name
- leftName :: Name
- rightName :: Name
- nonemptyName :: Name
Documentation
class Lift (t :: TYPE r) where Source #
A Lift
instance can have any of its values turned into a Template
Haskell expression. This is needed when a value used within a Template
Haskell quotation is bound outside the Oxford brackets ([| ... |]
or
[|| ... ||]
) but not at the top level. As an example:
add1 :: Int -> Code Q Int add1 x = [|| x + 1 ||]
Template Haskell has no way of knowing what value x
will take on at
splice-time, so it requires the type of x
to be an instance of Lift
.
A Lift
instance must satisfy $(lift x) ≡ x
and $$(liftTyped x) ≡ x
for all x
, where $(...)
and $$(...)
are Template Haskell splices.
It is additionally expected that
.lift
x ≡ unTypeCode
(liftTyped
x)
Lift
instances can be derived automatically by use of the -XDeriveLift
GHC language extension:
{-# LANGUAGE DeriveLift #-} module Foo where import Language.Haskell.TH.Syntax data Bar a = Bar1 a (Bar a) | Bar2 String deriving Lift
Representation-polymorphic since template-haskell-2.16.0.0.
lift :: Quote m => t -> m Exp Source #
Turn a value into a Template Haskell expression, suitable for use in a splice.
liftTyped :: forall (m :: Type -> Type). Quote m => t -> Code m t Source #
Turn a value into a Template Haskell typed expression, suitable for use in a typed splice.
Since: template-haskell-2.16.0.0
Instances
Lift Addr# Source # | Produces an Since: template-haskell-2.16.0.0 |
Lift Double# Source # | Since: template-haskell-2.16.0.0 |
Lift Float# Source # | Since: template-haskell-2.16.0.0 |
Lift Int# Source # | Since: template-haskell-2.16.0.0 |
Lift Void Source # | Since: template-haskell-2.15.0.0 |
Lift ForeignSrcLang Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => ForeignSrcLang -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => ForeignSrcLang -> Code m ForeignSrcLang Source # | |
Lift Int16 Source # | |
Lift Int32 Source # | |
Lift Int64 Source # | |
Lift Int8 Source # | |
Lift Extension Source # | Since: template-haskell-2.22.1.0 |
Lift AnnLookup Source # | Since: template-haskell-2.22.1.0 |
Lift AnnTarget Source # | Since: template-haskell-2.22.1.0 |
Lift Bang Source # | Since: template-haskell-2.22.1.0 |
Lift BndrVis Source # | Since: template-haskell-2.22.1.0 |
Lift Body Source # | Since: template-haskell-2.22.1.0 |
Lift Bytes Source # | Since: template-haskell-2.22.1.0 |
Lift Callconv Source # | Since: template-haskell-2.22.1.0 |
Lift Clause Source # | Since: template-haskell-2.22.1.0 |
Lift Con Source # | Since: template-haskell-2.22.1.0 |
Lift Dec Source # | Since: template-haskell-2.22.1.0 |
Lift DecidedStrictness Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => DecidedStrictness -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => DecidedStrictness -> Code m DecidedStrictness Source # | |
Lift DerivClause Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => DerivClause -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => DerivClause -> Code m DerivClause Source # | |
Lift DerivStrategy Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => DerivStrategy -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => DerivStrategy -> Code m DerivStrategy Source # | |
Lift DocLoc Source # | Since: template-haskell-2.22.1.0 |
Lift Exp Source # | Since: template-haskell-2.22.1.0 |
Lift FamilyResultSig Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => FamilyResultSig -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => FamilyResultSig -> Code m FamilyResultSig Source # | |
Lift Fixity Source # | Since: template-haskell-2.22.1.0 |
Lift FixityDirection Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => FixityDirection -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => FixityDirection -> Code m FixityDirection Source # | |
Lift Foreign Source # | Since: template-haskell-2.22.1.0 |
Lift FunDep Source # | Since: template-haskell-2.22.1.0 |
Lift Guard Source # | Since: template-haskell-2.22.1.0 |
Lift Info Source # | Since: template-haskell-2.22.1.0 |
Lift InjectivityAnn Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => InjectivityAnn -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => InjectivityAnn -> Code m InjectivityAnn Source # | |
Lift Inline Source # | Since: template-haskell-2.22.1.0 |
Lift Lit Source # | Since: template-haskell-2.22.1.0 |
Lift Loc Source # | Since: template-haskell-2.22.1.0 |
Lift Match Source # | Since: template-haskell-2.22.1.0 |
Lift ModName Source # | Since: template-haskell-2.22.1.0 |
Lift Module Source # | Since: template-haskell-2.22.1.0 |
Lift Name Source # | Since: template-haskell-2.22.1.0 |
Lift NameFlavour Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => NameFlavour -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => NameFlavour -> Code m NameFlavour Source # | |
Lift NameIs Source # | Since: template-haskell-2.22.1.0 |
Lift NameSpace Source # | Since: template-haskell-2.22.1.0 |
Lift NamespaceSpecifier Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => NamespaceSpecifier -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => NamespaceSpecifier -> Code m NamespaceSpecifier Source # | |
Lift OccName Source # | Since: template-haskell-2.22.1.0 |
Lift Overlap Source # | Since: template-haskell-2.22.1.0 |
Lift Pat Source # | Since: template-haskell-2.22.1.0 |
Lift PatSynArgs Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => PatSynArgs -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => PatSynArgs -> Code m PatSynArgs Source # | |
Lift PatSynDir Source # | Since: template-haskell-2.22.1.0 |
Lift Phases Source # | Since: template-haskell-2.22.1.0 |
Lift PkgName Source # | Since: template-haskell-2.22.1.0 |
Lift Pragma Source # | Since: template-haskell-2.22.1.0 |
Lift Range Source # | Since: template-haskell-2.22.1.0 |
Lift Role Source # | Since: template-haskell-2.22.1.0 |
Lift RuleBndr Source # | Since: template-haskell-2.22.1.0 |
Lift RuleMatch Source # | Since: template-haskell-2.22.1.0 |
Lift Safety Source # | Since: template-haskell-2.22.1.0 |
Lift SourceStrictness Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => SourceStrictness -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => SourceStrictness -> Code m SourceStrictness Source # | |
Lift SourceUnpackedness Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => SourceUnpackedness -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => SourceUnpackedness -> Code m SourceUnpackedness Source # | |
Lift Specificity Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => Specificity -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => Specificity -> Code m Specificity Source # | |
Lift Stmt Source # | Since: template-haskell-2.22.1.0 |
Lift TyLit Source # | Since: template-haskell-2.22.1.0 |
Lift TySynEqn Source # | Since: template-haskell-2.22.1.0 |
Lift Type Source # | Since: template-haskell-2.22.1.0 |
Lift TypeFamilyHead Source # | Since: template-haskell-2.22.1.0 |
Defined in GHC.Internal.TH.Lift lift :: Quote m => TypeFamilyHead -> m Exp Source # liftTyped :: forall (m :: Type -> Type). Quote m => TypeFamilyHead -> Code m TypeFamilyHead Source # | |
Lift Word16 Source # | |
Lift Word32 Source # | |
Lift Word64 Source # | |
Lift Word8 Source # | |
Lift Integer Source # | |
Lift Natural Source # | |
Lift () Source # | |
Lift Bool Source # | |
Lift Char Source # | |
Lift Double Source # | |
Lift Float Source # | |
Lift Int Source # | |
Lift Word Source # | |
Lift Char# Source # | Since: template-haskell-2.16.0.0 |
Lift Word# Source # | Since: template-haskell-2.16.0.0 |
Lift (# #) Source # | Since: template-haskell-2.16.0.0 |
Lift a => Lift (NonEmpty a :: Type) Source # | Since: template-haskell-2.15.0.0 |
Integral a => Lift (Ratio a :: Type) Source # | |
Lift a => Lift (TyVarBndr a :: Type) Source # | Since: template-haskell-2.22.1.0 |
Lift a => Lift (Maybe a :: Type) Source # | |
Lift a => Lift ([a] :: Type) Source # | |
(Lift a, Lift b) => Lift (Either a b :: Type) Source # | |
Lift (TExp a :: Type) Source # | Since: template-haskell-2.22.1.0 |
(Lift a, Lift b) => Lift ((a, b) :: Type) Source # | |
(Lift a, Lift b, Lift c) => Lift ((a, b, c) :: Type) Source # | |
(Lift a, Lift b, Lift c, Lift d) => Lift ((a, b, c, d) :: Type) Source # | |
(Lift a, Lift b, Lift c, Lift d, Lift e) => Lift ((a, b, c, d, e) :: Type) Source # | |
(Lift a, Lift b, Lift c, Lift d, Lift e, Lift f) => Lift ((a, b, c, d, e, f) :: Type) Source # | |
(Lift a, Lift b, Lift c, Lift d, Lift e, Lift f, Lift g) => Lift ((a, b, c, d, e, f, g) :: Type) Source # | |
Lift a => Lift ((# a #) :: TYPE ('TupleRep '[LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b) => Lift ((# a | b #) :: TYPE ('SumRep '[LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b) => Lift ((# a, b #) :: TYPE ('TupleRep '[LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c) => Lift ((# a | b | c #) :: TYPE ('SumRep '[LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c) => Lift ((# a, b, c #) :: TYPE ('TupleRep '[LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c, Lift d) => Lift ((# a | b | c | d #) :: TYPE ('SumRep '[LiftedRep, LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c, Lift d) => Lift ((# a, b, c, d #) :: TYPE ('TupleRep '[LiftedRep, LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c, Lift d, Lift e) => Lift ((# a | b | c | d | e #) :: TYPE ('SumRep '[LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c, Lift d, Lift e) => Lift ((# a, b, c, d, e #) :: TYPE ('TupleRep '[LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c, Lift d, Lift e, Lift f) => Lift ((# a | b | c | d | e | f #) :: TYPE ('SumRep '[LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c, Lift d, Lift e, Lift f) => Lift ((# a, b, c, d, e, f #) :: TYPE ('TupleRep '[LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c, Lift d, Lift e, Lift f, Lift g) => Lift ((# a | b | c | d | e | f | g #) :: TYPE ('SumRep '[LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
(Lift a, Lift b, Lift c, Lift d, Lift e, Lift f, Lift g) => Lift ((# a, b, c, d, e, f, g #) :: TYPE ('TupleRep '[LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep, LiftedRep])) Source # | Since: template-haskell-2.16.0.0 |
Generic Lift implementations
dataToQa :: (Quote m, Data a) => (Name -> k) -> (Lit -> m q) -> (k -> [m q] -> m q) -> (forall b. Data b => b -> Maybe (m q)) -> a -> m q Source #
dataToQa
is an internal utility function for constructing generic
conversion functions from types with Data
instances to various
quasi-quoting representations. See the source of dataToExpQ
and
dataToPatQ
for two example usages: mkCon
, mkLit
and appQ
are overloadable to account for different syntax for
expressions and patterns; antiQ
allows you to override type-specific
cases, a common usage is just const Nothing
, which results in
no overloading.
dataToExpQ :: (Quote m, Data a) => (forall b. Data b => b -> Maybe (m Exp)) -> a -> m Exp Source #
dataToExpQ
converts a value to a Exp
representation of the
same value, in the SYB style. It is generalized to take a function
override type-specific cases; see liftData
for a more commonly
used variant.
dataToPatQ :: (Quote m, Data a) => (forall b. Data b => b -> Maybe (m Pat)) -> a -> m Pat Source #
dataToPatQ
converts a value to a Pat
representation of the same
value, in the SYB style. It takes a function to handle type-specific cases,
alternatively, pass const Nothing
to get default behavior.
Wired-in names
nothingName :: Name Source #
nonemptyName :: Name Source #