twee-lib: An equational theorem prover

[ bsd3, library, 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.

This package contains only the library part of twee.

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  • Data
    • Primitive
      • ByteArray
        • Data.Primitive.ByteArray.Checked
      • Data.Primitive.Checked
      • SmallArray
        • Data.Primitive.SmallArray.Checked
  • Twee
    • Twee.Base
    • Twee.CP
    • Twee.Constraints
    • Twee.Equation
    • Twee.Index
    • Twee.Join
    • Twee.KBO
    • Twee.Label
    • Twee.PassiveQueue
    • Twee.Pretty
    • Twee.Proof
    • Twee.Rule
      • Twee.Rule.Index
    • Twee.Task
    • Twee.Term
    • Twee.Utils


Automatic Flags

Build a static binary.


Build a binary which statically links against libstdc++.


Build using LLVM backend for faster code.


Use bounds checks for all array operations.


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'.

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Versions [RSS] 2.1, 2.1.1, 2.1.2, 2.1.3, 2.1.4, 2.1.5, 2.2, 2.3, 2.3.1, 2.4, 2.4.1, 2.4.2
Dependencies base (>=4 && <4.11), containers, dlist, ghc-prim, pretty (>=, primitive (>=, transformers, vector [details]
License BSD-3-Clause
Author Nick Smallbone
Revised Revision 1 made by Bodigrim at 2022-08-16T22:54:26Z
Category Theorem Provers
Home page
Source repo head: git clone git:// -b master
Uploaded by NickSmallbone at 2018-02-07T23:11:50Z
Distributions NixOS:2.4.2
Reverse Dependencies 1 direct, 3 indirect [details]
Downloads 4654 total (20 in the last 30 days)
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Status Docs not available [build log]
Last success reported on 2018-02-08 [all 3 reports]

Readme for twee-lib-2.1

[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 in this repository, and then in the executable subdirectory. 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