Cycles in enhanced graph

[nschneid]

gum/_build/utils/eng_enhance.ini

Line 153 in 4777dc4

# relative in embedded PP ("to which","whose" -- whose would also need action #3~#1;#1:edep=nmod:poss; but this creates a cycle)

gum/_build/utils/eng_enhance.ini

Line 163 in 4777dc4

# exception to previous: prevent cycle when acl:relcl head has a coordinate predicate

These comments reference avoiding making the graph cyclic, but I think cycles are actually OK, as mentioned here. We just want to avoid self-edges.

[amir-zeldes]

In principle, yes, the edeps specification allows cycles. In practice though, ANNIS can't handle cycles in the same component, which is a somewhat complicated construct to explain. The basic gist is that cycles between regular deps and edeps are fine, but not within one of them. Since the build bot doesn't materialize edeps which are identical to basic deps, we can largely get away with edeps as intended. The few exceptions are the ones noted in the script, and currently GUM edeps lack those edges in conllu as well. Moving forward it would probably be nice to have these in conllu and either remove them before it goes to ANNIS, or find a different way to represent them (e.g. have another layer "edeps2" or something, which would be allowed to conflict with other edeps, or use a label instead of an edge somehow)

[nschneid]

Moving forward it would probably be nice to have these in conllu and either remove them before it goes to ANNIS, or find a different way to represent them

+1