Parsley.Defunctionalized

This module exports the Defunc type and associated patterns. These are by no means required to use Parsley, however they can serve as useful shortcuts to their regular Haskell equivalents. As they are in datatype form, they are inspectable by the internal Parsley machinery, which may improve optimisation opportunities or code generation.

Since: 0.1.0.0

Documentation

data Defunc a where

This datatype is useful for providing an inspectable representation of common Haskell functions. These can be provided in place of WQ to any combinator that requires it. The only difference is that the Parsley compiler is able to manipulate and match on the constructors, which might lead to optimisations. They can also be more convenient than constructing the WQ object itself:

ID ~= WQ id [||id||]
APP_H f x ~= WQ (f x) [||f x||]

Since: 0.1.0.0

Constructors

ID :: Defunc (a -> a)

Corresponds to the standard id function

COMPOSE :: Defunc ((b -> c) -> (a -> b) -> a -> c)

Corresponds to the standard (.) function applied to no arguments

FLIP :: Defunc ((a -> b -> c) -> b -> a -> c)

Corresponds to the standard flip function applied to no arguments

APP_H :: Defunc (a -> b) -> Defunc a -> Defunc b

Corresponds to function application of two other Defunc values

EQ_H :: Eq a => Defunc a -> Defunc (a -> Bool)

Corresponds to the partially applied (== x) for some Defunc value x

LIFTED :: (Show a, Lift a) => a -> Defunc a

Represents a liftable, showable value

CONS :: Defunc (a -> [a] -> [a])

Represents the standard (:) function applied to no arguments

CONST :: Defunc (a -> b -> a)

Represents the standard const function applied to no arguments

EMPTY :: Defunc [a]

Represents the empty list []

BLACK :: WQ a -> Defunc a

Wraps up any value of type WQ

IF_S :: Defunc Bool -> Defunc a -> Defunc a -> Defunc a

Represents the regular Haskell if syntax

Since: 0.1.1.0

LAM_S :: (Defunc a -> Defunc b) -> Defunc (a -> b)

Represents a Haskell lambda abstraction

Since: 0.1.1.0

LET_S :: Defunc a -> (Defunc a -> Defunc b) -> Defunc b

Represents a Haskell let binding

Since: 0.1.1.0

Instances

Quapplicative Defunc

This instance is used to manipulate values of Defunc.

Since: 0.1.0.0

Defined in Parsley.Internal.Core.Defunc

Methods

makeQ :: a -> Code a -> Defunc a

_val :: Defunc a -> a

_code :: Defunc a -> Code a

(>*<) :: Defunc (a -> b) -> Defunc a -> Defunc b

Show (Defunc a)

Defined in Parsley.Internal.Core.Defunc

Methods

showsPrec :: Int -> Defunc a -> ShowS

show :: Defunc a -> String

showList :: [Defunc a] -> ShowS

pattern UNIT :: Defunc ()

This pattern represents the unit value ()

Since: 0.1.0.0

pattern FLIP_CONST :: () => x ~ (a -> b -> b) => Defunc x

Represents the flipped standard const function applied to no arguments

Since: 0.1.0.0

pattern FLIP_H :: () => (x -> y) ~ ((a -> b -> c) -> b -> a -> c) => Defunc x -> Defunc y

This pattern corresponds to the standard flip function applied to a single argument

Since: 0.1.0.0

pattern COMPOSE_H :: () => (x -> y -> z) ~ ((b -> c) -> (a -> b) -> a -> c) => Defunc x -> Defunc y -> Defunc z

This pattern represents fully applied composition of two Defunc values

Since: 0.1.0.0