Cycles should be displayed inside the associated cluster

[srid]

Cycles are currently shown globally. But they must appear within their associated cluster.

To do this:

• Make mother return the list of subgraphs (instead of list of lists of zids)
• For each cluster, detect cycles and display them in the cluster's view.

[clojj]

@srid
So conceptually, cycles are Ok with Zettelkasten philosophy ?
If not, could you provide a link/information about Zettelkasten being driected acyclic graphs ?

[Nadrieril]

That's a good question: why should cycles be displayed as an error at all? They're quite natural

[srid]

@clojj There are two graphs here, conceptually:

• Zettelkasten connections graph: this is not acyclic.
• Zettelkasten folgezettel graph, which is a subset of the above, and should be acyclic (because it builds a heterarchy, which is a DAG).

The former includes "?cf" links (which can cyclically link to notes), while the later does not.

See Folgezettel Heterarchy.

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If you can understand what a folgezettel connection (as distinct from an ordinary connection (i.e., cf)) means, then you can see how a folgezettel heterarchy cannot be cyclic.

[srid]

Example of folgezettel heterarchy from my public zettelkasten: https://www.srid.ca/z-index.html

[Nadrieril]

Ah, I finally understand the distinction... I think it would be helpful to link to the documentation in the error message about cycles if it's not already the case.
That said, does it make semantic sense to ask the user to break a cycle at a potentially arbitrary point? Might it be possible to handle cycles in the folgezettel graph? If we do, a user can still break the cycle manually if they desire, but I find it annoying to force them to.

Here is how I think we could handle it. We would first compute the DAG of strongly connected components. When displaying the tree, you just follow the graph as before from the roots of that DAG. Since there is already a system to not display subtrees twice, I don't think cycles would break anything. The only problem is if a root is itself part of a cycle (i.e. a root component has more than one node), but then I think it's fine to break the cycle arbitrarily. The user can always break the cycle manually if needed.

[clojj]

@clojj There are two graphs here, conceptually:

* Zettelkasten connections graph: this is **not acyclic**.

* Zettelkasten folgezettel graph, which is a _subset_ of the above, and should be acyclic (because it builds a heterarchy, which is a DAG).

The former includes "?cf" links (which can cyclically link to notes), while the later does not.

See Folgezettel Heterarchy.

If you can understand what a folgezettel connection (as distinct from an ordinary connection (i.e., cf)) means, then you can see how a folgezettel heterarchy cannot be cyclic.

@srid thx for clarification !

[srid]

neuron doesn't look for cycles anymore.