Safe Haskell | Safe-Inferred |
---|---|

Language | Haskell2010 |

# Documentation

A list capable of storing values of different types. Creating an HList looks like.

1 ::: "test" ::: True ::: HNil

type family TypeMap (f :: a -> b) (xs :: [a]) where ... Source #

A map function over type level lists. For example, the following two lines are equivalent:

TypeMap Reader [Int, String, False] [Reader Int, Reader String, Reader Bool]

type family Append (a :: [t]) (b :: [t]) where ... Source #

Type-level append.

Append [Int, String] [Bool] [Int, String, Bool]

runSeveral :: (forall r' k x. k -> Sem (e k ': r') x -> Sem r' x) -> HList t -> Sem (Append (TypeMap e t) r) a -> Sem r a Source #

A helper function for building new runners which accept HLists intsead of individual elements. If you would normally write

f 5 . f "Text" . f True

then this function can turn that into

runSeveral f (True ::: "Text" ::: 5 ::: HNil)

For example, a runReaders function could be implemented as:

runReaders :: HList t -> Sem (TypeConcat (TypeMap Reader t) r) a -> Sem r a runReaders = runSeveral runReader

*Since: 0.1.0.0*