Open issues for 2.x

Hi @peter-empen,

the README mentions the improvements in the 2.x branch and especially the simplified type signatures might be helpful in our Petri Net library Kagera. You also mention that a lot is left to do there. The tests are all green, so the core part looks good. Is it the commented out dot and json sub-projects that need to be made working, or is there something else left to do?

[peter-empen]

FYI I’m working on “2. Drop Scala 2.12 compatibility” now.

[peter-empen]

It would be great if you found time to work on the unfinished parts. Some suggestions:

1. Just care about core first.
2. Drop Scala 2.12 compatibility by also merging back 2.13-specific folders and dropping compatibility helper types.
3. Rename State.scala- back to State.scala and make it compile. Refactor the accompanying test. To test State in isolation may require some more sophisticated test setup, though.
4. Rename GraphTraversal.scala- back to GraphTraversal.scala and make it compile. For the missing pieces try using ??? temporarily.
5. Continue with GraphTraversalImpl.scala- and TraverserImpl.scala-.
6. Once traversing sources compile, rename accompanying test sources back to Scala source files and refactor tests.

At this point you are almost done and, having bocome a Graph4Scala expert, you are able to continue on your own. 😄