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, 2.2, 2.3, 2.3.1
Dependencies ansi-terminal (>=0.9), base (<5), containers, jukebox (==0.5.*), pretty, split, symbol, twee-lib (==2.3.1) [details]
License BSD-3-Clause
Author Nick Smallbone
Category Theorem Provers
Home page
Source repo head: git clone git:// -b master
Uploaded by NickSmallbone at 2021-04-07T14:51:32Z
Distributions NixOS:2.3.1
Executables twee
Downloads 4177 total (18 in the last 30 days)
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Status Hackage Matrix CI
Docs pending
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Maintainer's Corner

For package maintainers and hackage trustees

Readme for twee-2.3.1

[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.

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