twee: An equational theorem prover

[ bsd3, program, theorem-provers ] [ Propose Tags ]

Twee is an experimental equational theorem prover based on Knuth-Bendix completion.

Given a set of equational axioms and a set of equational conjectures it will try to prove the conjectures. It will terminate if the conjectures are true but normally fail to terminate if they are false.

The input problem should be in TPTP format (see You can use types and quantifiers, but apart from that the problem must be equational.

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Versions [faq] 0.1, 2.0, 2.1, 2.1.1, 2.1.2, 2.1.3, 2.1.4, 2.1.5
Dependencies base (<5), containers, jukebox (==0.3.7), pretty, split, twee-lib (==2.1.5) [details]
License BSD-3-Clause
Author Nick Smallbone
Revised Revision 1 made by NickSmallbone at Tue Aug 14 09:22:00 UTC 2018
Category Theorem Provers
Home page
Source repo head: git clone git:// -b master
Uploaded by NickSmallbone at Wed May 2 13:38:08 UTC 2018
Distributions NixOS:2.1.5
Executables twee
Downloads 1561 total (122 in the last 30 days)
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Status Hackage Matrix CI
Docs not available [build log]
Last success reported on 2018-05-02 [all 3 reports]



Build a static binary.


Build a binary which statically links against libstdc++.


Build using LLVM backend for faster code.


Use -f <flag> to enable a flag, or -f -<flag> to disable that flag. More info


Note: This package has metadata revisions in the cabal description newer than included in the tarball. To unpack the package including the revisions, use 'cabal get'.

Maintainer's Corner

For package maintainers and hackage trustees

Readme for twee-2.1.5

[back to package description]

This is twee, an equational theorem prover.

The version in this git repository is likely to be unstable! To install the latest stable version, run:

cabal install twee

If you have LLVM installed, you can get a slightly faster version by running:

cabal install twee -fllvm

If you really want the latest unstable version, run cabal install src/ . in this repository. You will most likely need the latest git version of Jukebox, from, too - and things may break from time to time.

Afterwards, run twee nameofproblem.p. The problem should be in TPTP format ( You can find a few examples in the tests directory. All axioms and conjectures must be equations, but you can freely use quantifiers. If it succeeds in proving your problem, twee will print a human-readable proof.

For the official manual, see