ghc-typelits-natnormalise
GHC typechecker plugin for types of kind GHC.TypeLits.Nat
| Version on this page: | 0.2.1 |
| LTS Haskell 24.17: | 0.7.10 |
| Stackage Nightly 2025-10-30: | 0.9.1 |
| Latest on Hackage: | 0.9.1 |
Maintained by [email protected]
This version can be pinned in stack with:
ghc-typelits-natnormalise-0.2.1@sha256:6a05f58a782c24365df882812d647037dbc7e8a00a85aa80f7de3e0a0e433cc2,2276Module documentation for 0.2.1
Depends on 2 packages(full list with versions):
Used by 2 packages in nightly-2015-05-28(full list with versions):
ghc-tynat-normalise
A type checker plugin for GHC that can solve equalities
of types of kind Nat, where these types are either:
- Type-level naturals
- Type variables
- Applications of the arithmetic expressions
(+,-,*,^).
It solves these equalities by normalising them to sort-of
SOP (Sum-of-Products) form, and then perform a
simple syntactic equality.
For example, this solver can prove the equality between:
(x + 2)^(y + 2)
and
4*x*(2 + x)^y + 4*(2 + x)^y + (2 + x)^y*x^2
Because the latter is actually the SOP normal form
of the former.
To use the plugin, add
{-# OPTIONS_GHC -fplugin GHC.TypeLits.Normalise #-}
To the header of your file.