name: typelits-witnesses
version: 0.3.0.1
synopsis: Existential witnesses, singletons, and classes for operations on GHC TypeLits
description: Provides witnesses for 'KnownNat' and 'KnownSymbol'
instances for various operations on GHC TypeLits - in
particular, the arithmetic operations defined in
"GHC.TypeLits", and also for type-level lists of
'KnownNat' and 'KnownSymbol' instances.
.
This is useful for situations where you have
@'KnownNat' n@, and you want to prove to GHC
@'KnownNat' (n + 3)@, or @'KnownNat' (2*n + 4)@, or when
constraints on the lower or upper limits of @n@ are
needed.
.
It's also useful for when you want to work with type
level lists of 'KnownNat' or 'KnownSymbol' instances and
singletons for traversing them, and be able to apply
analogies of 'natVal' and 'symbolVal' to lists with
analogies for 'SomeNat' and 'SomeSymbol'.
.
Note that most of the functionality in this library can
be reproduced in a more generic way using the great
<https://hackage.haskell.org/package/singletons singletons>
library. The versions here are provided as a "plumbing
included" alternative that makes some commonly found
design patterns involving GHC's TypeLits functionality a
little smoother, especially when working with external
libraries or GHC TypeLit's Nat comparison API.
.
See README for more information.
homepage: https://github.com/mstksg/typelits-witnesses
license: MIT
license-file: LICENSE
author: Justin Le
maintainer: justin@jle.im
copyright: (c) Justin Le 2018
category: Data
build-type: Simple
extra-source-files: README.md
, CHANGELOG.md
cabal-version: >=1.10
tested-with: GHC == 7.8.4
, GHC == 7.10.3
, GHC == 8.0.2
, GHC == 8.2.1
source-repository head
type: git
location: git://github.com/mstksg/typelits-witnesses.git
library
exposed-modules: GHC.TypeLits.Witnesses
GHC.TypeLits.List
GHC.TypeLits.Compare
-- other-modules:
-- other-extensions:
if impl(ghc >= 8.0)
build-depends: base >=4.7 && <5
, base-compat
, constraints
, reflection >= 2
, transformers
else
build-depends: base >=4.7 && <5
, base-compat
, constraints < 0.9.1
, reflection >= 2
, transformers
hs-source-dirs: src
ghc-options: -Wall
default-language: Haskell2010