Metadata is perhaps most frequently used on vars: user=> (meta #'comp) {:arglists ([] [f] [f g] [f g & fs]), :doc "Takes a set of functions and returns a fn that is the composition\n of those fns. The returned fn takes a variable number of args,\n applies the rightmost of fns to the args, the next\n fn (right-to-left) to the result, etc.", :added "1.0", :static true, :line 2426, :column 1, :file "clojure/core.clj", :name comp, :ns #object[clojure.lang.Namespace 0x6cc8adff "clojure.core"]}
And for providing type hints to the compiler: (.endsWith ^String s ".txt") I've also made use of metadata in Ring to tell the session middleware to recreate the session with a new key: (defn handler [request] {:status 200 :headers {"Content-Type" "text/plain"} :session ^:recreate {:foo "bar"} :body "baz"}) And I've used metadata in Ittyon to denote whether a state transition is reproducible (i.e. generated by a pure function). - James On 5 August 2015 at 13:01, Eric Le Goff <eleg...@gmail.com> wrote: > The page http://clojure.org/metadata states that it "can also be used by > application developers for many purposes, annotating data sources, policy > etc." > > Could anyone elaborate about some real use case scenarios where they need > to use this metadata feature ? > > Regards, > > > -- > Eric Le Goff > http://fr.linkedin.com/in/elegoff > @elegoff <https://twitter.com/elegoff> > > -- > 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. 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.