Presburger Arithmetic Solver for GHC Type-level natural numbers.

Version on this page:
LTS Haskell 22.26:
Stackage Nightly 2024-06-18:
Latest on Hackage:

See all snapshots ghc-typelits-presburger appears in

BSD-3-Clause licensed by Hiromi ISHII
Maintained by konn.jinro _at_
This version can be pinned in stack with:ghc-typelits-presburger-,3252

Module documentation for

ghc-typelits-presburger augments GHC type-system with Presburger Arithmetic Solver for Type-level natural numbers. This plugin only work with GHC builtin operations. To work with those of singletons package, use ghc-typelits-meta and/or ghc-typelits-presburger instead.

Since, integration with singletons package moves to singletons-presburger.

You can use by adding this package to build-depends and add the following pragma to the head of .hs files:

OPTIONS_GHC -fplugin GHC.TypeLits.Presburger



  • Supports GHC 9.8
  • Drops support for GHC <9

  • Supports GHC 9.6
  • More robust equational-reasoning package detection logic.

  • Proper Support of GHC 9.4 (Now can solve Assert properly)

  • Support GHC 9.4
  • The plugin can solve constraints involving type-level Assert, Not, (&&), (||), and/or If from new base.

  • Support GHC 9.2.1
  • Decoding in Min/Max expression in terms of OrdCond

  • Stop discharging redundant constraints
  • Support GHC 9.0.1
  • Drop a support for GHC <8.6

  • Fixes constraint solving (fixes #9); this may change the previous (unsound) behaviour, and hence it is breaking change.

  • Supports GHC >= 8.10.

  • Drops support for GHC < 8.4
  • Entire overhaul.
  • Adds negated-numbers option.
  • Allows terms which includes uninterpreted terms (still much incomplete).
  • Separates singletons support as singletons-presburger package.
  • Provides an interface for extending solver with additional syntax constructs. See GHC.TypeLits.Presburger.Types module for more detail.