Having used both Clojure and RDF extensively I can say that there are many similarities between these two worlds, and the influence of RDF on Clojure isn't just something Rich say's, it's very apparant.
I may be mistaken in some of the details here, but as I understand it in the world of GOFAI (Good Old Fashioned AI) and KR (Knowledge Representation) there were "frame languages" popularised by Minsky: https://en.wikipedia.org/wiki/Frame_language where you essentially describe the world in terms of classes, and classes consist of sets of slots or properties, you may have inheritance etc... essentially classical OOP. In the other KR camp however you have First Order Predicate Logic (FOL), where the predicates (properties) essentially take centre stage, and describe relations between objects. This modelling camp is largely where RDF drew its inspiration for modelling from in the form of RDFS and OWL. I'd argue (with no authority) that FOL is likely the true source of the decomplected properties from maps idea in clojure; which is analagous to what happened in KR. I mention frame languages, as I suspect there is a lot of academic discourse on the pros and cons of frame based approaches vs FOL, which may be relevant. In RDFS (RDF Schema: https://en.wikipedia.org/wiki/RDF_Schema) and OWL ( https://en.wikipedia.org/wiki/Web_Ontology_Language )you essentially describe the domains and ranges of properties, and then use properties to tie things together. In these languages you don't think of classes as constraining the available properties. Infact properties often let you infer the class of something, for example if you learn that :Rick foaf:friend :Bill you also learn that :Rick and :Bill are foaf:Person's too. This enables anyone to say anything about anything in RDF which is why it's an open world system, where as frame based systems are typically closed world, as you can't add properties to something without changing the class. RDF and OWL aren't really constraint languages though, they're description logics; so they don't typically let you restrict the values of things, instead they let you infer new values. However recently there have been moves to standardise ways to check RDF graphs form a certain well specified shape. This has been in the form of the languages SheX and SHACL (now a W3C standard: https://www.w3.org/TR/shacl/ ). I find it remarkable how similar these languages are to spec; though I don't think spec drew any direct inspiration from them. I guess you just end up in a similar place if you share a property oriented view of the world. If you're interested in these languages this is a good online book on the topic: http://book.validatingrdf.com/index.html RDF also has a lot in common with Datomic in that you describe data with triples EAV(T) in datomic and SPO(G) in RDF. Likewise SPARQL and Datomic have a common ancestor in Datalog. I believe another non RDF influence for spec is this paper: http://matt.might.net/papers/might2011derivatives.pdf Please take all of the above with a pinch of salt though, it's at best a crude approximation on the lineage of these ideas... R. On Thu, 25 Apr 2019 at 08:16, Henning Sato von Rosen < henning.von.ro...@gmail.com> wrote: > On Thu, Apr 25, 2019 at 2:32 AM <dus...@hyperfiddle.net> wrote: > >> A lot of the attribute-centric thinking is inspired by RDF and linked-data >> > > Yes! Rich mentions that as well. So I tried to look into RDF, but it is > huge! If anybody has a good link to material relevant to this discussion, > I'm thankful, but at the time being we will likely not have time to dig > into RDF. Rich's explanation is by far the most relevant andaccessible > I've come across. > > Regards/Henning > > > > > >> -- >> You received this message because you are subscribed to the Google >> Groups "Clojure" group. >> To post to this group, send email to clojure@googlegroups.com >> Note that posts from new members are moderated - please be patient with >> your first post. >> To unsubscribe from this group, send email to >> clojure+unsubscr...@googlegroups.com >> For more options, visit this group at >> http://groups.google.com/group/clojure?hl=en >> --- >> You received this message because you are subscribed to a topic in the >> Google Groups "Clojure" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/clojure/Dbh-5kNYKgE/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> clojure+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with > your first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en > --- > You received this message because you are subscribed to the Google Groups > "Clojure" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to clojure+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Clojure" group. 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