Language.Haskell.TH

template-haskell-2.10.0.0: Support library for Template Haskell

Safe Haskell | None
Language | Haskell2010

Language.Haskell.TH

Contents

- The monad and its operations
  - Administration: errors, locations and IO
  - Querying the compiler
    - Reify
    - Name lookup
    - Instance lookup
    - Roles lookup
    - Annotation lookup
- Typed expressions
- Names
  - Constructing names
  - Deconstructing names
  - Built-in names
- The algebraic data types
  - Declarations
  - Expressions
  - Patterns
  - Types
- Library functions
  - Abbreviations
  - Constructors lifted to `Q`
    - Literals
    - Patterns
    - Pattern Guards
    - Expressions
      - Ranges
        - Ranges with more indirection
      - Statements
    - Types
      - Type literals
      - Strictness
      - Class Contexts
    - Kinds
    - Roles
    - Top Level Declarations
      - Data
      - Class
      - Role annotations
      - Type Family / Data Family
      - Foreign Function Interface (FFI)
      - Pragmas
- Pretty-printer

Description

The public face of Template Haskell

For other documentation, refer to: http://www.haskell.org/haskellwiki/Template_Haskell

Synopsis

- data Q a
- runQ :: Quasi m => Q a -> m a
- reportError :: String -> Q ()
- reportWarning :: String -> Q ()
- report :: Bool -> String -> Q ()
- recover :: Q a -> Q a -> Q a
- location :: Q Loc
- data Loc = Loc {
  - loc_filename :: String
  - loc_package :: String
  - loc_module :: String
  - loc_start :: CharPos
  - loc_end :: CharPos
  }
- runIO :: IO a -> Q a
- reify :: Name -> Q Info
- reifyModule :: Module -> Q ModuleInfo
- thisModule :: Q Module
- data Info
  - = ClassI Dec [InstanceDec]
  - | ClassOpI Name Type ParentName Fixity
  - | TyConI Dec
  - | FamilyI Dec [InstanceDec]
  - | PrimTyConI Name Arity Unlifted
  - | DataConI Name Type ParentName Fixity
  - | VarI Name Type (Maybe Dec) Fixity
  - | TyVarI Name Type
- data ModuleInfo = ModuleInfo [Module]
- type InstanceDec = Dec
- type ParentName = Name
- type Arity = Int
- type Unlifted = Bool
- lookupTypeName :: String -> Q (Maybe Name)
- lookupValueName :: String -> Q (Maybe Name)
- reifyInstances :: Name -> [Type] -> Q [InstanceDec]
- isInstance :: Name -> [Type] -> Q Bool
- reifyRoles :: Name -> Q [Role]
- reifyAnnotations :: Data a => AnnLookup -> Q [a]
- data AnnLookup
  - = AnnLookupModule Module
  - | AnnLookupName Name
- data TExp a
- unType :: TExp a -> Exp
- data Name
- data NameSpace
- mkName :: String -> Name
- newName :: String -> Q Name
- nameBase :: Name -> String
- nameModule :: Name -> Maybe String
- tupleTypeName :: Int -> Name
- tupleDataName :: Int -> Name
- unboxedTupleTypeName :: Int -> Name
- unboxedTupleDataName :: Int -> Name
- data Dec
  - = FunD Name [Clause]
  - | ValD Pat Body [Dec]
  - | DataD Cxt Name [TyVarBndr] [Con] [Name]
  - | NewtypeD Cxt Name [TyVarBndr] Con [Name]
  - | TySynD Name [TyVarBndr] Type
  - | ClassD Cxt Name [TyVarBndr] [FunDep] [Dec]
  - | InstanceD Cxt Type [Dec]
  - | SigD Name Type
  - | ForeignD Foreign
  - | InfixD Fixity Name
  - | PragmaD Pragma
  - | FamilyD FamFlavour Name [TyVarBndr] (Maybe Kind)
  - | DataInstD Cxt Name [Type] [Con] [Name]
  - | NewtypeInstD Cxt Name [Type] Con [Name]
  - | TySynInstD Name TySynEqn
  - | ClosedTypeFamilyD Name [TyVarBndr] (Maybe Kind) [TySynEqn]
  - | RoleAnnotD Name [Role]
  - | StandaloneDerivD Cxt Type
  - | DefaultSigD Name Type
- data Con
  - = NormalC Name [StrictType]
  - | RecC Name [VarStrictType]
  - | InfixC StrictType Name StrictType
  - | ForallC [TyVarBndr] Cxt Con
- data Clause = Clause [Pat] Body [Dec]
- data Strict
  - = IsStrict
  - | NotStrict
  - | Unpacked
- data Foreign
  - = ImportF Callconv Safety String Name Type
  - | ExportF Callconv String Name Type
- data Callconv
  - = CCall
  - | StdCall
  - | CApi
  - | Prim
  - | JavaScript
- data Safety
  - = Unsafe
  - | Safe
  - | Interruptible
- data Pragma
  - = InlineP Name Inline RuleMatch Phases
  - | SpecialiseP Name Type (Maybe Inline) Phases
  - | SpecialiseInstP Type
  - | RuleP String [RuleBndr] Exp Exp Phases
  - | AnnP AnnTarget Exp
  - | LineP Int String
- data Inline
  - = NoInline
  - | Inline
  - | Inlinable
- data RuleMatch
  - = ConLike
  - | FunLike
- data Phases
  - = AllPhases
  - | FromPhase Int
  - | BeforePhase Int
- data RuleBndr
  - = RuleVar Name
  - | TypedRuleVar Name Type
- data AnnTarget
  - = ModuleAnnotation
  - | TypeAnnotation Name
  - | ValueAnnotation Name
- data FunDep = FunDep [Name] [Name]
- data FamFlavour
  - = TypeFam
  - | DataFam
- data TySynEqn = TySynEqn [Type] Type
- data Fixity = Fixity Int FixityDirection
- data FixityDirection
  - = InfixL
  - | InfixR
  - | InfixN
- defaultFixity :: Fixity
- maxPrecedence :: Int
- data Exp
  - = VarE Name
  - | ConE Name
  - | LitE Lit
  - | AppE Exp Exp
  - | InfixE (Maybe Exp) Exp (Maybe Exp)
  - | UInfixE Exp Exp Exp
  - | ParensE Exp
  - | LamE [Pat] Exp
  - | LamCaseE [Match]
  - | TupE [Exp]
  - | UnboxedTupE [Exp]
  - | CondE Exp Exp Exp
  - | MultiIfE [(Guard, Exp)]
  - | LetE [Dec] Exp
  - | CaseE Exp [Match]
  - | DoE [Stmt]
  - | CompE [Stmt]
  - | ArithSeqE Range
  - | ListE [Exp]
  - | SigE Exp Type
  - | RecConE Name [FieldExp]
  - | RecUpdE Exp [FieldExp]
  - | StaticE Exp
- data Match = Match Pat Body [Dec]
- data Body
  - = GuardedB [(Guard, Exp)]
  - | NormalB Exp
- data Guard
  - = NormalG Exp
  - | PatG [Stmt]
- data Stmt
  - = BindS Pat Exp
  - | LetS [Dec]
  - | NoBindS Exp
  - | ParS [[Stmt]]
- data Range
  - = FromR Exp
  - | FromThenR Exp Exp
  - | FromToR Exp Exp
  - | FromThenToR Exp Exp Exp
- data Lit
  - = CharL Char
  - | StringL String
  - | IntegerL Integer
  - | RationalL Rational
  - | IntPrimL Integer
  - | WordPrimL Integer
  - | FloatPrimL Rational
  - | DoublePrimL Rational
  - | StringPrimL [Word8]
- data Pat
  - = LitP Lit
  - | VarP Name
  - | TupP [Pat]
  - | UnboxedTupP [Pat]
  - | ConP Name [Pat]
  - | InfixP Pat Name Pat
  - | UInfixP Pat Name Pat
  - | ParensP Pat
  - | TildeP Pat
  - | BangP Pat
  - | AsP Name Pat
  - | WildP
  - | RecP Name [FieldPat]
  - | ListP [Pat]
  - | SigP Pat Type
  - | ViewP Exp Pat
- type FieldExp = (Name, Exp)
- type FieldPat = (Name, Pat)
- data Type
  - = ForallT [TyVarBndr] Cxt Type
  - | AppT Type Type
  - | SigT Type Kind
  - | VarT Name
  - | ConT Name
  - | PromotedT Name
  - | TupleT Int
  - | UnboxedTupleT Int
  - | ArrowT
  - | EqualityT
  - | ListT
  - | PromotedTupleT Int
  - | PromotedNilT
  - | PromotedConsT
  - | StarT
  - | ConstraintT
  - | LitT TyLit
- data TyVarBndr
  - = PlainTV Name
  - | KindedTV Name Kind
- data TyLit
  - = NumTyLit Integer
  - | StrTyLit String
- type Kind = Type
- type Cxt = [Pred]
- type Pred = Type
- data Role
  - = NominalR
  - | RepresentationalR
  - | PhantomR
  - | InferR
- type InfoQ = Q Info
- type ExpQ = Q Exp
- type DecQ = Q Dec
- type DecsQ = Q [Dec]
- type ConQ = Q Con
- type TypeQ = Q Type
- type TyLitQ = Q TyLit
- type CxtQ = Q Cxt
- type PredQ = Q Pred
- type MatchQ = Q Match
- type ClauseQ = Q Clause
- type BodyQ = Q Body
- type GuardQ = Q Guard
- type StmtQ = Q Stmt
- type RangeQ = Q Range
- type StrictTypeQ = Q StrictType
- type VarStrictTypeQ = Q VarStrictType
- type PatQ = Q Pat
- type FieldPatQ = Q FieldPat
- type RuleBndrQ = Q RuleBndr
- type TySynEqnQ = Q TySynEqn
- intPrimL :: Integer -> Lit
- wordPrimL :: Integer -> Lit
- floatPrimL :: Rational -> Lit
- doublePrimL :: Rational -> Lit
- integerL :: Integer -> Lit
- rationalL :: Rational -> Lit
- charL :: Char -> Lit
- stringL :: String -> Lit
- stringPrimL :: [Word8] -> Lit
- litP :: Lit -> PatQ
- varP :: Name -> PatQ
- tupP :: [PatQ] -> PatQ
- conP :: Name -> [PatQ] -> PatQ
- uInfixP :: PatQ -> Name -> PatQ -> PatQ
- parensP :: PatQ -> PatQ
- infixP :: PatQ -> Name -> PatQ -> PatQ
- tildeP :: PatQ -> PatQ
- bangP :: PatQ -> PatQ
- asP :: Name -> PatQ -> PatQ
- wildP :: PatQ
- recP :: Name -> [FieldPatQ] -> PatQ
- listP :: [PatQ] -> PatQ
- sigP :: PatQ -> TypeQ -> PatQ
- viewP :: ExpQ -> PatQ -> PatQ
- fieldPat :: Name -> PatQ -> FieldPatQ
- normalB :: ExpQ -> BodyQ
- guardedB :: [Q (Guard, Exp)] -> BodyQ
- normalG :: ExpQ -> GuardQ
- normalGE :: ExpQ -> ExpQ -> Q (Guard, Exp)
- patG :: [StmtQ] -> GuardQ
- patGE :: [StmtQ] -> ExpQ -> Q (Guard, Exp)
- match :: PatQ -> BodyQ -> [DecQ] -> MatchQ
- clause :: [PatQ] -> BodyQ -> [DecQ] -> ClauseQ
- dyn :: String -> ExpQ
- global :: Name -> ExpQ
- varE :: Name -> ExpQ
- conE :: Name -> ExpQ
- litE :: Lit -> ExpQ
- appE :: ExpQ -> ExpQ -> ExpQ
- uInfixE :: ExpQ -> ExpQ -> ExpQ -> ExpQ
- parensE :: ExpQ -> ExpQ
- staticE :: ExpQ -> ExpQ
- infixE :: Maybe ExpQ -> ExpQ -> Maybe ExpQ -> ExpQ
- infixApp :: ExpQ -> ExpQ -> ExpQ -> ExpQ
- sectionL :: ExpQ -> ExpQ -> ExpQ
- sectionR :: ExpQ -> ExpQ -> ExpQ
- lamE :: [PatQ] -> ExpQ -> ExpQ
- lam1E :: PatQ -> ExpQ -> ExpQ
- lamCaseE :: [MatchQ] -> ExpQ
- tupE :: [ExpQ] -> ExpQ
- condE :: ExpQ -> ExpQ -> ExpQ -> ExpQ
- multiIfE :: [Q (Guard, Exp)] -> ExpQ
- letE :: [DecQ] -> ExpQ -> ExpQ
- caseE :: ExpQ -> [MatchQ] -> ExpQ
- appsE :: [ExpQ] -> ExpQ
- listE :: [ExpQ] -> ExpQ
- sigE :: ExpQ -> TypeQ -> ExpQ
- recConE :: Name -> [Q (Name, Exp)] -> ExpQ
- recUpdE :: ExpQ -> [Q (Name, Exp)] -> ExpQ
- stringE :: String -> ExpQ
- fieldExp :: Name -> ExpQ -> Q (Name, Exp)
- fromE :: ExpQ -> ExpQ
- fromThenE :: ExpQ -> ExpQ -> ExpQ
- fromToE :: ExpQ -> ExpQ -> ExpQ
- fromThenToE :: ExpQ -> ExpQ -> ExpQ -> ExpQ
- arithSeqE :: RangeQ -> ExpQ
- fromR :: ExpQ -> RangeQ
- fromThenR :: ExpQ -> ExpQ -> RangeQ
- fromToR :: ExpQ -> ExpQ -> RangeQ
- fromThenToR :: ExpQ -> ExpQ -> ExpQ -> RangeQ
- doE :: [StmtQ] -> ExpQ
- compE :: [StmtQ] -> ExpQ
- bindS :: PatQ -> ExpQ -> StmtQ
- letS :: [DecQ] -> StmtQ
- noBindS :: ExpQ -> StmtQ
- parS :: [[StmtQ]] -> StmtQ
- forallT :: [TyVarBndr] -> CxtQ -> TypeQ -> TypeQ
- varT :: Name -> TypeQ
- conT :: Name -> TypeQ
- appT :: TypeQ -> TypeQ -> TypeQ
- arrowT :: TypeQ
- equalityT :: TypeQ
- listT :: TypeQ
- tupleT :: Int -> TypeQ
- sigT :: TypeQ -> Kind -> TypeQ
- litT :: TyLitQ -> TypeQ
- promotedT :: Name -> TypeQ
- promotedTupleT :: Int -> TypeQ
- promotedNilT :: TypeQ
- promotedConsT :: TypeQ
- numTyLit :: Integer -> TyLitQ
- strTyLit :: String -> TyLitQ
- isStrict :: Q Strict
- notStrict :: Q Strict
- strictType :: Q Strict -> TypeQ -> StrictTypeQ
- varStrictType :: Name -> StrictTypeQ -> VarStrictTypeQ
- cxt :: [PredQ] -> CxtQ
- classP :: Name -> [Q Type] -> Q Pred
- equalP :: TypeQ -> TypeQ -> PredQ
- normalC :: Name -> [StrictTypeQ] -> ConQ
- recC :: Name -> [VarStrictTypeQ] -> ConQ
- infixC :: Q (Strict, Type) -> Name -> Q (Strict, Type) -> ConQ
- forallC :: [TyVarBndr] -> CxtQ -> ConQ -> ConQ
- varK :: Name -> Kind
- conK :: Name -> Kind
- tupleK :: Int -> Kind
- arrowK :: Kind
- listK :: Kind
- appK :: Kind -> Kind -> Kind
- starK :: Kind
- constraintK :: Kind
- nominalR :: Role
- representationalR :: Role
- phantomR :: Role
- inferR :: Role
- valD :: PatQ -> BodyQ -> [DecQ] -> DecQ
- funD :: Name -> [ClauseQ] -> DecQ
- tySynD :: Name -> [TyVarBndr] -> TypeQ -> DecQ
- dataD :: CxtQ -> Name -> [TyVarBndr] -> [ConQ] -> [Name] -> DecQ
- newtypeD :: CxtQ -> Name -> [TyVarBndr] -> ConQ -> [Name] -> DecQ
- classD :: CxtQ -> Name -> [TyVarBndr] -> [FunDep] -> [DecQ] -> DecQ
- instanceD :: CxtQ -> TypeQ -> [DecQ] -> DecQ
- sigD :: Name -> TypeQ -> DecQ
- standaloneDerivD :: CxtQ -> TypeQ -> DecQ
- defaultSigD :: Name -> TypeQ -> DecQ
- roleAnnotD :: Name -> [Role] -> DecQ
- familyNoKindD :: FamFlavour -> Name -> [TyVarBndr] -> DecQ
- familyKindD :: FamFlavour -> Name -> [TyVarBndr] -> Kind -> DecQ
- dataInstD :: CxtQ -> Name -> [TypeQ] -> [ConQ] -> [Name] -> DecQ
- closedTypeFamilyNoKindD :: Name -> [TyVarBndr] -> [TySynEqnQ] -> DecQ
- closedTypeFamilyKindD :: Name -> [TyVarBndr] -> Kind -> [TySynEqnQ] -> DecQ
- newtypeInstD :: CxtQ -> Name -> [TypeQ] -> ConQ -> [Name] -> DecQ
- tySynInstD :: Name -> TySynEqnQ -> DecQ
- typeFam :: FamFlavour
- dataFam :: FamFlavour
- tySynEqn :: [TypeQ] -> TypeQ -> TySynEqnQ
- cCall :: Callconv
- stdCall :: Callconv
- cApi :: Callconv
- prim :: Callconv
- javaScript :: Callconv
- unsafe :: Safety
- safe :: Safety
- forImpD :: Callconv -> Safety -> String -> Name -> TypeQ -> DecQ
- ruleVar :: Name -> RuleBndrQ
- typedRuleVar :: Name -> TypeQ -> RuleBndrQ
- pragInlD :: Name -> Inline -> RuleMatch -> Phases -> DecQ
- pragSpecD :: Name -> TypeQ -> Phases -> DecQ
- pragSpecInlD :: Name -> TypeQ -> Inline -> Phases -> DecQ
- pragSpecInstD :: TypeQ -> DecQ
- pragRuleD :: String -> [RuleBndrQ] -> ExpQ -> ExpQ -> Phases -> DecQ
- pragAnnD :: AnnTarget -> ExpQ -> DecQ
- pragLineD :: Int -> String -> DecQ
- class Ppr a where
  - ppr :: a -> Doc
  - ppr_list :: [a] -> Doc
- pprint :: Ppr a => a -> String
- pprExp :: Precedence -> Exp -> Doc
- pprLit :: Precedence -> Lit -> Doc
- pprPat :: Precedence -> Pat -> Doc
- pprParendType :: Type -> Doc

# The monad and its operations

data Q a Source

Instances

Monad Q |
Functor Q |
Applicative Q |
Quasi Q |

runQ :: Quasi m => Q a -> m a Source

## Administration: errors, locations and IO

reportError :: String -> Q () Source

Report an error to the user, but allow the current splice's computation to carry on. To abort the computation, use `fail`.

reportWarning :: String -> Q () Source

Report a warning to the user, and carry on.

report :: Bool -> String -> Q () Source

Deprecated: Use reportError or reportWarning instead

Report an error (True) or warning (False), but carry on; use `fail` to stop.

recover Source

Arguments

:: Q a | handler to invoke on failure
-> Q a | computation to run
-> Q a |

Recover from errors raised by `reportError` or `fail`.

location :: Q Loc Source

The location at which this computation is spliced.

data Loc Source

Constructors

Loc |
Fields loc_filename :: String loc_package :: String loc_module :: String loc_start :: CharPos loc_end :: CharPos

Instances

Eq Loc |
Data Loc |
Ord Loc |
Show Loc |
Generic Loc |
Ppr Loc |
type Rep Loc |

runIO :: IO a -> Q a Source

The `runIO` function lets you run an I/O computation in the `Q` monad. Take care: you are guaranteed the ordering of calls to `runIO` within a single `Q` computation, but not about the order in which splices are run.

Note: for various murky reasons, stdout and stderr handles are not necessarily flushed when the compiler finishes running, so you should flush them yourself.

## Querying the compiler

### Reify

reify :: Name -> Q Info Source

`reify` looks up information about the `Name`.

It is sometimes useful to construct the argument name using `lookupTypeName` or `lookupValueName` to ensure that we are reifying from the right namespace. For instance, in this context:

    data D = D

which `D` does `reify (mkName "D")` return information about? (Answer: `D`-the-type, but don't rely on it.) To ensure we get information about `D`-the-value, use `lookupValueName`:

    do
      Just nm <- lookupValueName "D"
      reify nm

and to get information about `D`-the-type, use `lookupTypeName`.

reifyModule :: Module -> Q ModuleInfo Source

`reifyModule mod` looks up information about module `mod`. To look up the current module, call this function with the return value of `thisModule`.

thisModule :: Q Module Source

Return the Module at the place of splicing. Can be used as an input for `reifyModule`.

data Info Source

Obtained from `reify` in the `Q` Monad.

Constructors

ClassI Dec [InstanceDec] | A class, with a list of its visible instances
ClassOpI Name Type ParentName Fixity | A class method
TyConI Dec | A "plain" type constructor. "Fancier" type constructors are returned using `PrimTyConI` or `FamilyI` as appropriate
FamilyI Dec [InstanceDec] | A type or data family, with a list of its visible instances. A closed type family is returned with 0 instances.
PrimTyConI Name Arity Unlifted | A "primitive" type constructor, which can't be expressed with a `Dec`. Examples: `(->)`, `Int#`.
DataConI Name Type ParentName Fixity | A data constructor
VarI Name Type (Maybe Dec) Fixity | A "value" variable (as opposed to a type variable, see `TyVarI`). The `Maybe Dec` field contains `Just` the declaration which defined the variable -- including the RHS of the declaration -- or else `Nothing`, in the case where the RHS is unavailable to the compiler. At present, this value is _always_ `Nothing`: returning the RHS has not yet been implemented because of lack of interest.
TyVarI Name Type | A type variable. The `Type` field contains the type which underlies the variable. At present, this is always ``VarT` theName`, but future changes may permit refinement of this.

Instances

Eq Info |
Data Info |
Ord Info |
Show Info |
Generic Info |
Ppr Info |
type Rep Info |

data ModuleInfo Source

Obtained from `reifyModule` in the `Q` Monad.

Constructors

ModuleInfo [Module] | Contains the import list of the module.

Instances

Eq ModuleInfo |
Data ModuleInfo |
Ord ModuleInfo |
Show ModuleInfo |
Generic ModuleInfo |
Ppr ModuleInfo |
type Rep ModuleInfo |

type InstanceDec = Dec Source

`InstanceDec` desribes a single instance of a class or type function. It is just a `Dec`, but guaranteed to be one of the following:

- `InstanceD` (with empty `[`Dec`]`)
- `DataInstD` or `NewtypeInstD` (with empty derived `[`Name`]`)
- `TySynInstD`

type ParentName = Name Source

In `ClassOpI` and `DataConI`, name of the parent class or type

type Arity = Int Source

In `PrimTyConI`, arity of the type constructor

type Unlifted = Bool Source

In `PrimTyConI`, is the type constructor unlifted?

### Name lookup

lookupTypeName :: String -> Q (Maybe Name) Source

Look up the given name in the (type namespace of the) current splice's scope. See Language.Haskell.TH.Syntax for more details.

lookupValueName :: String -> Q (Maybe Name) Source

Look up the given name in the (value namespace of the) current splice's scope. See Language.Haskell.TH.Syntax for more details.

### Instance lookup

reifyInstances :: Name -> [Type] -> Q [InstanceDec] Source

`reifyInstances nm tys` returns a list of visible instances of `nm tys`. That is, if `nm` is the name of a type class, then all instances of this class at the types `tys` are returned. Alternatively, if `nm` is the name of a data family or type family, all instances of this family at the types `tys` are returned.

isInstance :: Name -> [Type] -> Q Bool Source

Is the list of instances returned by `reifyInstances` nonempty?

### Roles lookup

reifyRoles :: Name -> Q [Role] Source

`reifyRoles nm` returns the list of roles associated with the parameters of the tycon `nm`. Fails if `nm` cannot be found or is not a tycon. The returned list should never contain `InferR`.

### Annotation lookup

reifyAnnotations :: Data a => AnnLookup -> Q [a] Source

`reifyAnnotations target` returns the list of annotations associated with `target`. Only the annotations that are appropriately typed is returned. So if you have `Int` and `String` annotations for the same target, you have to call this function twice.

data AnnLookup Source

Annotation target for reifyAnnotations

Constructors

AnnLookupModule Module |
AnnLookupName Name |

Instances

Eq AnnLookup |
Data AnnLookup |
Ord AnnLookup |
Show AnnLookup |
Generic AnnLookup |
type Rep AnnLookup |

# Typed expressions

data TExp a Source

unType :: TExp a -> Exp Source

# Names

data Name Source

An abstract type representing names in the syntax tree.

`Name`s can be constructed in several ways, which come with different name-capture guarantees (see Language.Haskell.TH.Syntax for an explanation of name capture):

- the built-in syntax `'f` and `''T` can be used to construct names, The expression `'f` gives a `Name` which refers to the value `f` currently in scope, and `''T` gives a `Name` which refers to the type `T` currently in scope. These names can never be captured.
- `lookupValueName` and `lookupTypeName` are similar to `'f` and `''T` respectively, but the `Name`s are looked up at the point where the current splice is being run. These names can never be captured.
- `newName` monadically generates a new name, which can never be captured.
- `mkName` generates a capturable name.

Names constructed using `newName` and `mkName` may be used in bindings (such as `let x = ...` or `x -> ...`), but names constructed using `lookupValueName`, `lookupTypeName`, `'f`, `''T` may not.

Instances

Eq Name |
Data Name |
Ord Name |
Show Name |
Generic Name |
Ppr Name |
type Rep Name |

data NameSpace Source

Instances

Eq NameSpace |
Data NameSpace |
Ord NameSpace |
Generic NameSpace |
type Rep NameSpace |

## Constructing names

mkName :: String -> Name Source

Generate a capturable name. Occurrences of such names will be resolved according to the Haskell scoping rules at the occurrence site.

For example:

    f = [| pi + $(varE (mkName "pi")) |]
    ...
    g = let pi = 3 in $f

In this case, `g` is desugared to

    g = Prelude.pi + 3

Note that `mkName` may be used with qualified names:

    mkName "Prelude.pi"

See also `dyn` for a useful combinator. The above example could be rewritten using `dyn` as

    f = [| pi + $(dyn "pi") |]

newName :: String -> Q Name Source

Generate a fresh name, which cannot be captured.

For example, this:

    f = $(do
      nm1 <- newName "x"
      let nm2 = mkName "x"
      return (LamE [VarP nm1] (LamE [VarP nm2] (VarE nm1)))
     )

will produce the splice

    f = \x0 -> \x -> x0

In particular, the occurrence `VarE nm1` refers to the binding `VarP nm1`, and is not captured by the binding `VarP nm2`.

Although names generated by `newName` cannot be captured, they can capture other names. For example, this:

    g = $(do
      nm1 <- newName "x"
      let nm2 = mkName "x"
      return (LamE [VarP nm2] (LamE [VarP nm1] (VarE nm2)))
     )

will produce the splice

    g = \x -> \x0 -> x0

since the occurrence `VarE nm2` is captured by the innermost binding of `x`, namely `VarP nm1`.

## Deconstructing names

nameBase :: Name -> String Source

The name without its module prefix

nameModule :: Name -> Maybe String Source

Module prefix of a name, if it exists

## Built-in names

tupleTypeName :: Int -> Name Source

Tuple type constructor

tupleDataName :: Int -> Name Source

Tuple data constructor

unboxedTupleTypeName :: Int -> Name Source

Unboxed tuple type constructor

unboxedTupleDataName :: Int -> Name Source

Unboxed tuple data constructor

# The algebraic data types

The lowercase versions (syntax operators) of these constructors are preferred to these constructors, since they compose better with quotations (`[| |]`) and splices (`$( ... )`)

## Declarations

data Dec Source

Constructors

FunD Name [Clause] |
    { f p1 p2 = b where decs }
ValD Pat Body [Dec] |
    { p = b where decs }
DataD Cxt Name [TyVarBndr] [Con] [Name] |
    { data Cxt x => T x = A x | B (T x)
           deriving (Z,W)}
NewtypeD Cxt Name [TyVarBndr] Con [Name] |
    { newtype Cxt x => T x = A (B x)
           deriving (Z,W)}
TySynD Name [TyVarBndr] Type |
    { type T x = (x,x) }
ClassD Cxt Name [TyVarBndr] [FunDep] [Dec] |
    { class Eq a => Ord a where ds }
InstanceD Cxt Type [Dec] |
    { instance Show w => Show [w]
           where ds }
SigD Name Type |
    { length :: [a] -> Int }
ForeignD Foreign |
    { foreign import ... }
    { foreign export ... }
InfixD Fixity Name |
    { infix 3 foo }
PragmaD Pragma |
    { {--} }
FamilyD FamFlavour Name [TyVarBndr] (Maybe Kind) |
    { type family T a b c :: * }
DataInstD Cxt Name [Type] [Con] [Name] |
    { data instance Cxt x => T [x] = A x
                                    | B (T x)
           deriving (Z,W)}
NewtypeInstD Cxt Name [Type] Con [Name] |
    { newtype instance Cxt x => T [x] = A (B x)
           deriving (Z,W)}
TySynInstD Name TySynEqn |
    { type instance ... }
ClosedTypeFamilyD Name [TyVarBndr] (Maybe Kind) [TySynEqn] |
    { type family F a b :: * where ... }
RoleAnnotD Name [Role] |
    { type role T nominal representational }
StandaloneDerivD Cxt Type |
    { deriving instance Ord a => Ord (Foo a) }
DefaultSigD Name Type |
    { default size :: Data a => a -> Int }

Instances

Eq Dec |
Data Dec |
Ord Dec |
Show Dec |
Generic Dec |
Ppr Dec |
type Rep Dec |

data Con Source

Constructors

NormalC Name [StrictType] |
    C Int a
RecC Name [VarStrictType] |
    C { v :: Int, w :: a }
InfixC StrictType Name StrictType |
    Int :+ a
ForallC [TyVarBndr] Cxt Con |
    forall a. Eq a => C [a]

Instances

Eq Con |
Data Con |
Ord Con |
Show Con |
Generic Con |
Ppr Con |
type Rep Con |

data Clause Source

Constructors

Clause [Pat] Body [Dec] |
    f { p1 p2 = body where decs }

Instances

Eq Clause |
Data Clause |
Ord Clause |
Show Clause |
Generic Clause |
Ppr Clause |
type Rep Clause |

data Strict Source

Constructors

IsStrict |
NotStrict |
Unpacked |

Instances

Eq Strict |
Data Strict |
Ord Strict |
Show Strict |
Generic Strict |
type Rep Strict |

data Foreign Source

Constructors

ImportF Callconv Safety String Name Type |
ExportF Callconv String Name Type |

Instances

Eq Foreign |
Data Foreign |
Ord Foreign |
Show Foreign |
Generic Foreign |
Ppr Foreign |
type Rep Foreign |

data Callconv Source

Constructors

CCall |
StdCall |
CApi |
Prim |
JavaScript |

Instances

Eq Callconv |
Data Callconv |
Ord Callconv |
Show Callconv |
Generic Callconv |
type Rep Callconv |

data Safety Source

Constructors

Unsafe |
Safe |
Interruptible |

Instances

Eq Safety |
Data Safety |
Ord Safety |
Show Safety |
Generic Safety |
type Rep Safety |

data Pragma Source

Constructors

InlineP Name Inline RuleMatch Phases |
SpecialiseP Name Type (Maybe Inline) Phases |
SpecialiseInstP Type |
RuleP String [RuleBndr] Exp Exp Phases |
AnnP AnnTarget Exp |
LineP Int String |

Instances

Eq Pragma |
Data Pragma |
Ord Pragma |
Show Pragma |
Generic Pragma |
Ppr Pragma |
type Rep Pragma |

data Inline Source

Constructors

NoInline |
Inline |
Inlinable |

Instances

Eq Inline |
Data Inline |
Ord Inline |
Show Inline |
Generic Inline |
Ppr Inline |
type Rep Inline |

data RuleMatch Source

Constructors

ConLike |
FunLike |

Instances

Eq RuleMatch |
Data RuleMatch |
Ord RuleMatch |
Show RuleMatch |
Generic RuleMatch |
Ppr RuleMatch |
type Rep RuleMatch |

data Phases Source

Constructors

AllPhases |
FromPhase Int |
BeforePhase Int |

Instances

Eq Phases |
Data Phases |
Ord Phases |
Show Phases |
Generic Phases |
Ppr Phases |
type Rep Phases |

data RuleBndr Source

Constructors

RuleVar Name |
TypedRuleVar Name Type |

Instances

Eq RuleBndr |
Data RuleBndr |
Ord RuleBndr |
Show RuleBndr |
Generic RuleBndr |
Ppr RuleBndr |
type Rep RuleBndr |

data AnnTarget Source

Constructors

ModuleAnnotation |
TypeAnnotation Name |
ValueAnnotation Name |

Instances

Eq AnnTarget |
Data AnnTarget |
Ord AnnTarget |
Show AnnTarget |
Generic AnnTarget |
type Rep AnnTarget |

data FunDep Source

Constructors

FunDep [Name] [Name] |

Instances

Eq FunDep |
Data FunDep |
Ord FunDep |
Show FunDep |
Generic FunDep |
Ppr FunDep |
type Rep FunDep |

data FamFlavour Source

Constructors

TypeFam |
DataFam |

Instances

Eq FamFlavour |
Data FamFlavour |
Ord FamFlavour |
Show FamFlavour |
Generic FamFlavour |
Ppr FamFlavour |
type Rep FamFlavour |

data TySynEqn Source

One equation of a type family instance or closed type family. The arguments are the left-hand-side type patterns and the right-hand-side result.

Constructors

TySynEqn [Type] Type |

Instances

Eq TySynEqn |
Data TySynEqn |
Ord TySynEqn |
Show TySynEqn |
Generic TySynEqn |
type Rep TySynEqn |

data Fixity Source

Constructors

Fixity Int FixityDirection |

Instances

Eq Fixity |
Data Fixity |
Ord Fixity |
Show Fixity |
Generic Fixity |
type Rep Fixity |

data FixityDirection Source

Constructors

InfixL |
InfixR |
InfixN |

Instances

Eq FixityDirection |
Data FixityDirection |
Ord FixityDirection |
Show FixityDirection |
Generic FixityDirection |
type Rep FixityDirection |

defaultFixity :: Fixity Source

Default fixity: `infixl 9`

maxPrecedence :: Int Source

Highest allowed operator precedence for `Fixity` constructor (answer: 9)

## Expressions

data Exp Source

Constructors

VarE Name |
    { x }
ConE Name |
    data T1 = C1 t1 t2; p = {C1} e1 e2
LitE Lit |
    { 5 or c}
AppE Exp Exp |
    { f x }
InfixE (Maybe Exp) Exp (Maybe Exp) |
    {x + y} or {(x+)} or {(+ x)} or {(+)}
UInfixE Exp Exp Exp |
    {x + y}
See Language.Haskell.TH.Syntax
ParensE Exp |
    { (e) }
See Language.Haskell.TH.Syntax
LamE [Pat] Exp |
    {  p1 p2 -> e }
LamCaseE [Match] |
    { case m1; m2 }
TupE [Exp] |
    { (e1,e2) }
UnboxedTupE [Exp] |
    { () }
CondE Exp Exp Exp |
    { if e1 then e2 else e3 }
MultiIfE [(Guard, Exp)] |
    { if | g1 -> e1 | g2 -> e2 }
LetE [Dec] Exp |
    { let x=e1;   y=e2 in e3 }
CaseE Exp [Match] |
    { case e of m1; m2 }
DoE [Stmt] |
    { do { p <- e1; e2 }  }
CompE [Stmt] |
    { [ (x,y) | x <- xs, y <- ys ] }
The result expression of the comprehension is the last of the ``Stmt``s, and should be a `NoBindS`. E.g. translation:
    [ f x | x <- xs ]
    CompE [BindS (VarP x) (VarE xs), NoBindS (AppE (VarE f) (VarE x))]
ArithSeqE Range |
    { [ 1 ,2 .. 10 ] }
ListE [Exp] |
    { [1,2,3] }
SigE Exp Type |
    { e :: t }
RecConE Name [FieldExp] |
    { T { x = y, z = w } }
RecUpdE Exp [FieldExp] |
    { (f x) { z = w } }
StaticE Exp |
    { static e }

Instances

Eq Exp |
Data Exp |
Ord Exp |
Show Exp |
Generic Exp |
Ppr Exp |
type Rep Exp |

data Match Source

Constructors

Match Pat Body [Dec] |
    case e of { pat -> body where decs }

Instances

Eq Match |
Data Match |
Ord Match |
Show Match |
Generic Match |
Ppr Match |
type Rep Match |

data Body Source

Constructors

GuardedB [(Guard, Exp)] |
    f p { | e1 = e2
          | e3 = e4 }
     where ds
NormalB Exp |
    f p { = e } where ds

Instances

Eq Body |
Data Body |
Ord Body |
Show Body |
Generic Body |
type Rep Body |

data Guard Source

Constructors

NormalG Exp |
    f x { | odd x } = x
PatG [Stmt] |
    f x { | Just y <- x, Just z <- y } = z

Instances

Eq Guard |
Data Guard |
Ord Guard |
Show Guard |
Generic Guard |
type Rep Guard |

data Stmt Source

Constructors

BindS Pat Exp |
LetS [Dec] |
NoBindS Exp |
ParS [[Stmt]] |

Instances

Eq Stmt |
Data Stmt |
Ord Stmt |
Show Stmt |
Generic Stmt |
Ppr Stmt |
type Rep Stmt |

data Range Source

Constructors

FromR Exp |
FromThenR Exp Exp |
FromToR Exp Exp |
FromThenToR Exp Exp Exp |

Instances

Eq Range |
Data Range |
Ord Range |
Show Range |
Generic Range |
Ppr Range |
type Rep Range |

data Lit Source

Constructors

CharL Char |
StringL String |
IntegerL Integer | Used for overloaded and non-overloaded literals. We don't have a good way to represent non-overloaded literals at the moment. Maybe that doesn't matter?
RationalL Rational |
IntPrimL Integer |
WordPrimL Integer |
FloatPrimL Rational |
DoublePrimL Rational |
StringPrimL [Word8] | A primitive C-style string, type Addr#

Instances

Eq Lit |
Data Lit |
Ord Lit |
Show Lit |
Generic Lit |
Ppr Lit |
type Rep Lit |

## Patterns

data Pat Source

Pattern in Haskell given in `{}`

Constructors

LitP Lit |
    { 5 or c }
VarP Name |
    { x }
TupP [Pat] |
    { (p1,p2) }
UnboxedTupP [Pat] |
    { () }
ConP Name [Pat] |
    data T1 = C1 t1 t2; {C1 p1 p1} = e
InfixP Pat Name Pat |
    foo ({x :+ y}) = e
UInfixP Pat Name Pat |
    foo ({x :+ y}) = e
See Language.Haskell.TH.Syntax
ParensP Pat |
    {(p)}
See Language.Haskell.TH.Syntax
TildeP Pat |
    { ~p }
BangP Pat |
    { !p }
AsP Name Pat |
    { x @ p }
WildP |
    { _ }
RecP Name [FieldPat] |
    f (Pt { pointx = x }) = g x
ListP [Pat] |
    { [1,2,3] }
SigP Pat Type |
    { p :: t }
ViewP Exp Pat |
    { e -> p }

Instances

Eq Pat |
Data Pat |
Ord Pat |
Show Pat |
Generic Pat |
Ppr Pat |
type Rep Pat |

type FieldExp = (Name, Exp) Source

type FieldPat = (Name, Pat) Source

## Types

data Type Source

Constructors

ForallT [TyVarBndr] Cxt Type |
    forall <vars>. <ctxt> -> <type>
AppT Type Type |
    T a b
SigT Type Kind |
    t :: k
VarT Name |
    a
ConT Name |
    T
PromotedT Name |
    'T
TupleT Int |
    (,), (,,), etc.
UnboxedTupleT Int |
    (), (), etc.
ArrowT |
    ->
EqualityT |
    ~
ListT |
    []
PromotedTupleT Int |
    '(), '(,), '(,,), etc.
PromotedNilT |
    '[]
PromotedConsT |
    (':)
StarT |
    *
ConstraintT |
    Constraint
LitT TyLit |
    0,1,2, etc.

Instances

Eq Type |
Data Type |
Ord Type |
Show Type |
Generic Type |
Ppr Type |
type Rep Type |

data TyVarBndr Source

Constructors

PlainTV Name |
    a
KindedTV Name Kind |
    (a :: k)

Instances

Eq TyVarBndr |
Data TyVarBndr |
Ord TyVarBndr |
Show TyVarBndr |
Generic TyVarBndr |
Ppr TyVarBndr |
type Rep TyVarBndr |

data TyLit Source

Constructors

NumTyLit Integer |
    2
StrTyLit String |
    Hello

Instances

Eq TyLit |
Data TyLit |
Ord TyLit |
Show TyLit |
Generic TyLit |
Ppr TyLit |
type Rep TyLit |

type Kind = Type Source

To avoid duplication between kinds and types, they are defined to be the same. Naturally, you would never have a type be `StarT` and you would never have a kind be `SigT`, but many of the other constructors are shared. Note that the kind `Bool` is denoted with `ConT`, not `PromotedT`. Similarly, tuple kinds are made with `TupleT`, not `PromotedTupleT`.

type Cxt Source

Arguments

= [Pred] |
    (Eq a, Ord b)

type Pred = Type Source

Since the advent of `ConstraintKinds`, constraints are really just types. Equality constraints use the `EqualityT` constructor. Constraints may also be tuples of other constraints.

data Role Source

Role annotations

Constructors

NominalR |
    nominal
RepresentationalR |
    representational
PhantomR |
    phantom
InferR |
    _

Instances

Eq Role |
Data Role |
Ord Role |
Show Role |
Generic Role |
Ppr Role |
type Rep Role |

# Library functions

## Abbreviations

type InfoQ = Q Info Source

type ExpQ = Q Exp Source

type DecQ = Q Dec Source

type DecsQ = Q [Dec] Source

type ConQ = Q Con Source

type TypeQ = Q Type Source

type TyLitQ = Q TyLit Source

type CxtQ = Q Cxt Source

type PredQ = Q Pred Source

type MatchQ = Q Match Source

type ClauseQ = Q Clause Source

type BodyQ = Q Body Source

type GuardQ = Q Guard Source

type StmtQ = Q Stmt Source

type RangeQ = Q Range Source

type StrictTypeQ = Q StrictType Source

type VarStrictTypeQ = Q VarStrictType Source

type PatQ = Q Pat Source

type FieldPatQ = Q FieldPat Source

type RuleBndrQ = Q RuleBndr Source

type TySynEqnQ = Q TySynEqn Source

## Constructors lifted to `Q`

### Literals

intPrimL :: Integer -> Lit Source

wordPrimL :: Integer -> Lit Source

floatPrimL :: Rational -> Lit Source

doublePrimL :: Rational -> Lit Source

integerL :: Integer -> Lit Source

rationalL :: Rational -> Lit Source

charL :: Char -> Lit Source

stringL :: String -> Lit Source

stringPrimL :: [Word8] -> Lit Source

### Patterns

litP :: Lit -> PatQ Source

varP :: Name -> PatQ Source

tupP :: [PatQ] -> PatQ Source

conP :: Name -> [PatQ] -> PatQ Source

uInfixP :: PatQ -> Name -> PatQ -> PatQ Source

parensP :: PatQ -> PatQ Source

infixP :: PatQ -> Name -> PatQ -> PatQ Source

tildeP :: PatQ -> PatQ Source

bangP :: PatQ -> PatQ Source

asP :: Name -> PatQ -> PatQ Source

wildP :: PatQ Source

recP :: Name -> [FieldPatQ] -> PatQ Source

listP :: [PatQ] -> PatQ Source

sigP :: PatQ -> TypeQ -> PatQ Source

viewP :: ExpQ -> PatQ -> PatQ Source

fieldPat :: Name -> PatQ -> FieldPatQ Source

### Pattern Guards

normalB :: ExpQ -> BodyQ Source

guardedB :: [Q (Guard, Exp)] -> BodyQ Source

normalG :: ExpQ -> GuardQ Source

normalGE :: ExpQ -> ExpQ -> Q (Guard, Exp) Source

patG :: [StmtQ] -> GuardQ Source

patGE :: [StmtQ] -> ExpQ -> Q (Guard, Exp) Source

match :: PatQ -> BodyQ -> [DecQ] -> MatchQ Source

Use with `caseE`

clause :: [PatQ] -> BodyQ -> [DecQ] -> ClauseQ Source

Use with `funD`

### Expressions

dyn :: String -> ExpQ Source

Dynamically binding a variable (unhygenic)

global :: Name -> ExpQ Source

Deprecated: Use varE instead

varE :: Name -> ExpQ Source

conE :: Name -> ExpQ Source

litE :: Lit -> ExpQ Source

appE :: ExpQ -> ExpQ -> ExpQ Source

uInfixE :: ExpQ -> ExpQ -> ExpQ -> ExpQ Source

parensE :: ExpQ -> ExpQ Source

staticE :: ExpQ -> ExpQ Source

    staticE x = [| static x |]

infixE :: Maybe ExpQ -> ExpQ -> Maybe ExpQ -> ExpQ Source

infixApp :: ExpQ -> ExpQ -> ExpQ -> ExpQ Source

sectionL :: ExpQ -> ExpQ -> ExpQ Source

sectionR :: ExpQ -> ExpQ -> ExpQ Source

lamE :: [PatQ] -> ExpQ -> ExpQ Source

lam1E :: PatQ -> ExpQ -> ExpQ Source

Single-arg lambda

lamCaseE :: [MatchQ] -> ExpQ Source

tupE :: [ExpQ] -> ExpQ Source

condE :: ExpQ -> ExpQ -> ExpQ -> ExpQ Source

multiIfE :: [Q (Guard, Exp)] -> ExpQ Source

letE :: [DecQ] -> ExpQ -> ExpQ Source

caseE :: ExpQ -> [MatchQ] -> ExpQ Source

appsE :: [ExpQ] -> ExpQ Source

listE :: [ExpQ] -> ExpQ Source

sigE :: ExpQ -> TypeQ -> ExpQ Source

recConE :: Name -> [Q (Name, Exp)] -> ExpQ Source

recUpdE :: ExpQ -> [Q (Name, Exp)] -> ExpQ Source

stringE :: String -> ExpQ Source

fieldExp :: Name -> ExpQ -> Q (Name, Exp) Source

#### Ranges

fromE :: ExpQ -> ExpQ Source

fromThenE :: ExpQ -> ExpQ -> ExpQ Source

fromToE :: ExpQ -> ExpQ -> ExpQ Source

fromThenToE :: ExpQ -> ExpQ -> ExpQ -> ExpQ Source

#### Ranges with more indirection

arithSeqE :: RangeQ -> ExpQ Source

fromR :: ExpQ -> RangeQ Source

fromThenR :: ExpQ -> ExpQ -> RangeQ Source

fromToR :: ExpQ -> ExpQ -> RangeQ Source

fromThenToR :: ExpQ -> ExpQ -> ExpQ -> RangeQ Source

#### Statements

doE :: [StmtQ] -> ExpQ Source

compE :: [StmtQ] -> ExpQ Source

bindS :: PatQ -> ExpQ -> StmtQ Source

letS :: [DecQ] -> StmtQ Source

noBindS :: ExpQ -> StmtQ Source

parS :: [[StmtQ]] -> StmtQ Source

### Types

forallT :: [TyVarBndr] -> CxtQ -> TypeQ -> TypeQ Source

varT :: Name -> TypeQ Source

conT :: Name -> TypeQ Source

appT :: TypeQ -> TypeQ -> TypeQ Source

arrowT :: TypeQ Source

equalityT :: TypeQ Source

listT :: TypeQ Source

tupleT :: Int -> TypeQ Source

sigT :: TypeQ -> Kind -> TypeQ Source

litT :: TyLitQ -> TypeQ Source

promotedT :: Name -> TypeQ Source

promotedTupleT :: Int -> TypeQ Source

promotedNilT :: TypeQ Source

promotedConsT :: TypeQ Source

#### Type literals

numTyLit :: Integer -> TyLitQ Source

strTyLit :: String -> TyLitQ Source

#### Strictness

isStrict :: Q Strict Source

notStrict :: Q Strict Source

strictType :: Q Strict -> TypeQ -> StrictTypeQ Source

varStrictType :: Name -> StrictTypeQ -> VarStrictTypeQ Source

#### Class Contexts

cxt :: [PredQ] -> CxtQ Source

classP :: Name -> [Q Type] -> Q Pred Source

Deprecated: As of template-haskell-2.10, constraint predicates (Pred) are just types (Type), in keeping with ConstraintKinds. Please use `conT` and `appT`.

equalP :: TypeQ -> TypeQ -> PredQ Source

Deprecated: As of template-haskell-2.10, constraint predicates (Pred) are just types (Type), in keeping with ConstraintKinds. Please see `equalityT`.

normalC :: Name -> [StrictTypeQ] -> ConQ Source

recC :: Name -> [VarStrictTypeQ] -> ConQ Source

infixC :: Q (Strict, Type) -> Name -> Q (Strict, Type) -> ConQ Source

forallC :: [TyVarBndr] -> CxtQ -> ConQ -> ConQ Source

### Kinds

varK :: Name -> Kind Source

conK :: Name -> Kind Source

tupleK :: Int -> Kind Source

arrowK :: Kind Source

listK :: Kind Source

appK :: Kind -> Kind -> Kind Source

starK :: Kind Source

constraintK :: Kind Source

### Roles

nominalR :: Role Source

representationalR :: Role Source

phantomR :: Role Source

inferR :: Role Source

### Top Level Declarations

#### Data

valD :: PatQ -> BodyQ -> [DecQ] -> DecQ Source

funD :: Name -> [ClauseQ] -> DecQ Source

tySynD :: Name -> [TyVarBndr] -> TypeQ -> DecQ Source

dataD :: CxtQ -> Name -> [TyVarBndr] -> [ConQ] -> [Name] -> DecQ Source

newtypeD :: CxtQ -> Name -> [TyVarBndr] -> ConQ -> [Name] -> DecQ Source

#### Class

classD :: CxtQ -> Name -> [TyVarBndr] -> [FunDep] -> [DecQ] -> DecQ Source

instanceD :: CxtQ -> TypeQ -> [DecQ] -> DecQ Source

sigD :: Name -> TypeQ -> DecQ Source

standaloneDerivD :: CxtQ -> TypeQ -> DecQ Source

defaultSigD :: Name -> TypeQ -> DecQ Source

#### Role annotations

roleAnnotD :: Name -> [Role] -> DecQ Source

#### Type Family / Data Family

familyNoKindD :: FamFlavour -> Name -> [TyVarBndr] -> DecQ Source

familyKindD :: FamFlavour -> Name -> [TyVarBndr] -> Kind -> DecQ Source

dataInstD :: CxtQ -> Name -> [TypeQ] -> [ConQ] -> [Name] -> DecQ Source

closedTypeFamilyNoKindD :: Name -> [TyVarBndr] -> [TySynEqnQ] -> DecQ Source

closedTypeFamilyKindD :: Name -> [TyVarBndr] -> Kind -> [TySynEqnQ] -> DecQ Source

newtypeInstD :: CxtQ -> Name -> [TypeQ] -> ConQ -> [Name] -> DecQ Source

tySynInstD :: Name -> TySynEqnQ -> DecQ Source

typeFam :: FamFlavour Source

dataFam :: FamFlavour Source

tySynEqn :: [TypeQ] -> TypeQ -> TySynEqnQ Source

#### Foreign Function Interface (FFI)

cCall :: Callconv Source

stdCall :: Callconv Source

cApi :: Callconv Source

prim :: Callconv Source

javaScript :: Callconv Source

unsafe :: Safety Source

safe :: Safety Source

forImpD :: Callconv -> Safety -> String -> Name -> TypeQ -> DecQ Source

#### Pragmas

ruleVar :: Name -> RuleBndrQ Source

typedRuleVar :: Name -> TypeQ -> RuleBndrQ Source

pragInlD :: Name -> Inline -> RuleMatch -> Phases -> DecQ Source

pragSpecD :: Name -> TypeQ -> Phases -> DecQ Source

pragSpecInlD :: Name -> TypeQ -> Inline -> Phases -> DecQ Source

pragSpecInstD :: TypeQ -> DecQ Source

pragRuleD :: String -> [RuleBndrQ] -> ExpQ -> ExpQ -> Phases -> DecQ Source

pragAnnD :: AnnTarget -> ExpQ -> DecQ Source

pragLineD :: Int -> String -> DecQ Source

# Pretty-printer

class Ppr a where Source

Minimal complete definition

ppr

Methods

ppr :: a -> Doc Source

ppr_list :: [a] -> Doc Source

Instances

Ppr Exp |
Ppr Match |
Ppr Clause |
Ppr Pat |
Ppr Type |
Ppr Dec |
Ppr Name |
Ppr FunDep |
Ppr TyVarBndr |
Ppr Role |
Ppr TyLit |
Ppr Con |
Ppr RuleBndr |
Ppr Phases |
Ppr RuleMatch |
Ppr Inline |
Ppr Pragma |
Ppr Foreign |
Ppr FamFlavour |
Ppr Range |
Ppr Stmt |
Ppr Lit |
Ppr ModuleInfo |
Ppr Info |
Ppr Loc |
Ppr Module |
Ppr a => Ppr [a] |

pprint :: Ppr a => a -> String Source

pprExp :: Precedence -> Exp -> Doc Source

pprLit :: Precedence -> Lit -> Doc Source

pprPat :: Precedence -> Pat -> Doc Source

pprParendType :: Type -> Doc Source