Hi Amirouche, Amirouche <amirou...@hypermove.net> skribis:
> Le 09/02/2017 à 10:55, Ludovic Courtès a écrit : [...] >> I agree that this is asking for generalization. >> >> Another instance of DAG rewriting is the ‘package-with-’ helpers in >> (guix build-system gnu). >> >> We should have a general form of transformation procedure that handles >> DAG traversal and memoization like all these procedures do. > > FWIW, I am very much interested in what you will come up with. > > How is different what you want to achieve from SXML Tree Fold [0]? Here’s we’re dealing with DAGs, not just trees, so the notion of ‘up’ and ‘down’ doesn’t directly apply. But apart from that, we’re essentially writing a combinator to traverse the DAG, which is similar. > Wikipedia's graph rewriting [2] page cites a few softwares that deals with > the issue along with some theory. > > [2] https://en.wikipedia.org/wiki/Graph_rewriting > > The place where I will need DAG rewriting is the replacement ReLeX (from > opencog which AFAIK does graph rewriting somehow) and semantic/intent > framing. [...] > WDYT of my rambling? Heheh. :-) I think it’s interesting, but I’m not sure the actual pieces of software you mention could be used here. At this point we have fairly simple use cases, and a rewriting procedure like ‘package-input-rewriting’ is around 20 lines of code. That said, there’s a need for generalized graph tools, and also tools in (guix graph) that would allow us to get various graph metrics efficiently (things like computing the “rank” of a node). So if you’re into graphs you might be interested in fiddling with (guix graph) and see what cool things could be done. Thanks, Ludo’.
