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A two-level approach to prove tautologies using Stålmarck's algorithm in Coq.


Building and installation instructions

The easiest way to install the latest released version of Stalmarck is via OPAM:

opam repo add coq-released
opam install coq-stalmarck

To instead build and install manually, do:

git clone
cd stalmarck
make   # or make -j <number-of-cores-on-your-machine> 
make install


This project is composed of:

  • A Coq proof of correctness of the algorithm, as described in the paper A Formalization of Stålmarck's Algorithm in Coq, published in the proceedings of TPHOLs 2000.
  • an implementation of the algorithm. With respect to the paper, this implementation is completely functional and can be used inside Coq.
  • A reflected Coq tactic staltac that uses the extracted code to compute an execution trace; the trace checker is then called inside Coq.
  • A standalone checker program stalmarck which takes as input a formula in textual format and reports whether it can be certified as a tautology.

See algoRun.v for examples how to use the algorithm inside Coq, and see StalTac_ex.v for examples how to use the reflected tactic.