Web.Respond.HListUtils

These are some tools for working with HLists; this is relevant when you are using path extractors.

Documentation

type family HListElim ts a :: *

this type family represents functions that can take all of the elements of an HList.

Instances

type HListElim ([] *) a = a

type HListElim ((:) * t ts) a = t -> HListElim ts a

type HList0 = HList []

empty HList (useful for keeping other modules from needing to add several language extensions).

type HList1 a = HList `[a]`

HList with one element.

hListUncurry :: HListElim ts a -> HList ts -> a

uncurrys a function by applying it to the elements of the HList.

hListMapTo1 :: HListElim ts a -> HList ts -> HList1 a

uncurrys the function by applying it to the HList, then returns the result of that uncurrying as a single-element HList. useful for transforming PathExtractors.