GPL'd dependency: hopcroftkarp library about matchpy

[hbarthels]

Thank you for letting us know. Indeed, we've been thinking about getting rid of that dependency: #16

Where can we find that code?

[Upabjojr]

Sorry, forgot to share the link:
https://github.com/symengine/symengine/blob/9cb6da759fb95e2ffece407e0cf2bad136a3933b/matchpygen/bipartite.h#L126

[skirpichev]

@Upabjojr, hopcroftkarp library is one-person project. Maybe you could just convince its author to release code under a more permissive license. I think, LGPL-3 would be enough.

[hbarthels]

@Upabjojr, hopcroftkarp library is one-person project. Maybe you could just convince its author to release code under a more permissive license. I think, LGPL-3 would be enough.

Good point.

@sofiatolaosebikan As you may have noticed, MatchPy uses your hopcroftkarp package, and MatchPy in turn may end up being used by some other projects, for example SymPy. If I understand that correctly, it might be a problem for some of those other projects that hopcroftkarp uses the GPLv3 license. Would you be willing to use a more permissive license?

[sofiatolaosebikan]

@Upabjojr, hopcroftkarp library is one-person project. Maybe you could just convince its author to release code under a more permissive license. I think, LGPL-3 would be enough.

Good point.

@sofiatolaosebikan As you may have noticed, MatchPy uses your hopcroftkarp package, and MatchPy in turn may end up being used by some other projects, for example SymPy. If I understand that correctly, it might be a problem for some of those other projects that hopcroftkarp uses the GPLv3 license. Would you be willing to use a more permissive license?

@hbarthels: Yes, I would be happy to release the hopcroftkarp library under a licence that would be suitable for all the projects depending on it. I received a similar request from @jvdillon who suggested "MIT Licence" or "Apache 2 Licence". Would any one of these be sufficient?

[hbarthels]

@hbarthels: Yes, I would be happy to release the hopcroftkarp library under a licence that would be suitable for all the projects depending on it. I received a similar request from @jvdillon who suggested "MIT Licence" or "Apache 2 Licence". Would any one of these be sufficient?

Thank you, but we just added an internal implementation of the algorithm to MatchPy with #64, so we don't need the hopcroftkarp package anymore.