This aims to be a library implementing the rules of wéiqí/igo/baduk, allowing us to prove properties of game states. For example, I would like to prove that any shape with two sufficiently small eyes is alive.

The rules to be implemented are the Tromp-Taylor rules, which have area scoring, positional superko, and no dead stone removal. I might also require white passing last, depending on how things go.

The project is structured as follows. Igo contains definitions and proofs of anything immediately go-related. Other modules provide things to extend the standard library. Of particular note is Enum, defined in Relation.Unary.Enum, where Enum P is an exhaustive finite listing of all values satisfying P. Also commonly used is Rats from Data.Star.Rats, which is the backwards version of Star (reflexive-transitive closure). In a graph with edges E, Rats E s v is the type of paths starting at s and ending at v which are extended at the v end.

The standard library is the only dependency.

The current problem is to find a group of connected stones from a given stone. This is a special case of finding a connected component of a graph given a vertex in it, which I am trying to solve in Relation.Binary.Graph.