Control.Plumbers.TH

This module is used to generate operators that follow the plumbers symbolic convention for routing parameters.

Documentation

data PlumberSpec

Specifies all of the information needed to implement a plumber.

Constructors

PlumberSpec

Fields

• plumberOpE :: Exp -> Exp -> Exp

  The plumber implementation

• plumberTypes :: Maybe PlumberTypes

  Optional explicit type signatures

• plumberArities :: [Int]

  Arities to generate - 26 is max

• plumberPrefix :: String

  Prefix to use for operator

baseSpec :: String -> String -> PlumberSpec

Creates a plumber spec for the given prefix for the generated operators, and the name of the infix operator to use to construct the implementation.

data PlumberTypes

Specifies all of the information needed to construct type declarations for the plumber.

Constructors

PlumberTypes

Fields

• leftType :: Type

  Type of the left argument's result

• rightType :: Type

  Type of the right argument's result

• resultType :: Type

  Results type. This needs to be wrapped in a forall naming all of the utilized type variables.

baseTypes :: PlumberTypes

A basic set of types, which make r' the left type, and r'' the right type. The resultType is a forall that introduces these type variables, and has undefined content. Therefore any implementation in terms of baseTypes needs to redefine resultType, as the Forall has undefined as its content.

implementPlumbers :: PlumberSpec -> DecsQ

Implements all of the plumbers specified by the given PlumberSpec.

implementPlumber :: PlumberSpec -> String -> DecsQ

Implement only the specific plumber requested.

operatorNames :: PlumberSpec -> [[String]]

All of the operator names that the given PlumberSpec would implement.

aritiesString :: PlumberSpec -> String

For now this is just a string-yielding function, to be evaluated by the user, to generate the line defining the fixities. This code should be pasted below the TH invocation of implementPlumbers

TH Utilities

appsT :: [Type] -> Type

arrowsT :: [Type] -> Type

tuplesT :: [Type] -> Type

mkVE :: String -> Exp

mkVP :: String -> Pat

mkVT :: String -> Type

mkVB :: String -> TyVarBndr

addForalls :: Type -> Type -> Type