Peter Empen

Unfortunately not. Otherwise the issue would be closed. :) Does the above work around help? If not, why not?

Here is the whole story: First, it is just _immutable_ collections that should have covariant type parameters. _Mutable_ ones should not. Second, Graph for Scala defines graphs in in terms...

Currently, you can `findCycles` and `findCycleContaining(node)` but unfortunately `findSimpleCycles` is not supported. You may think about trying something like suggested at https://stackoverflow.com/questions/546655/finding-all-cycles-in-a-directed-graph.

@b-hass Of course it would.

The return type of `topologicalSort`, `TopologicalOrder` includes the layers. However, by `println(topOrder)` you force its default representation, a plain sequence. To get the layers along with the nodes they contain...

Right, you cannot get all orders, just "several valid topological orders". So it would be beneficial to add support for this. For the time being you could try to do...

Great. Just keep in mind that to prevent stack overflow, your algorithm should also be tail recursive. But that could be not an issue in your domain.

Unfortunately, core is half done. I renamed test source files because they were in way when refactoring step by step: https://github.com/scala-graph/scala-graph/tree/2.x/core/src/test/scala/scalax/collection. Notably the traversing part is still missing.

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...

FYI I'm working on "2. Drop Scala 2.12 compatibility" now.