On 23 August 2017 at 03:48, Didier <didi...@gmail.com> wrote: > I can see it be quick and concise for representing events, but that's also > exactly the use case example for multi-spec: https://clojure. > org/guides/spec#_multi_spec > > What happens if your event needs more data? Maybe draw needs 2 attributes, > the card and the deck? Now you have implicit encoding, where what the > attributes are for the event are defined by its position in the vector. >
Sometimes it's an advantage to have a deliberately constrained format, particularly when it comes to storage or indexing. Datomic, for instance, is effectively an indexed event log of [e a v t] tuples. If you're in a situation where the event data can and may expand, then use a map. But I'd argue that there are situations where the scope is limited, or you want a deliberate and hard constraint on what data is in an event. Another possible situation is if you're parsing map data incrementally. For example, a Ring request map could be read in as a series of key/value pairs: GET /example HTTP/1.1 Host: www.example.com [:request/method :get] [:request/uri "/example"] [:request/protocol "HTTP/1.1"] [:request/header ["host" "www.example.com"]] I'm not saying that variants should be favoured over maps in all situations; just that there are situations where you're certain that you need key/value pairings. -- James Reeves booleanknot.com -- 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.
