This approach would only work in ClojureScript, where IDeref is defined as a Protocol. In Clojure(JVM), the core functions are defined in terms of Java interfaces, which are not extensible to `nil`.
I don't find atom-or-nil to be a common value pattern. But if it's something you encounter frequently, you could work with it by either: - defining functions to return (atom nil) instead of nil - defining your own nil-safe version of deref –S On Friday, September 9, 2016 at 4:10:11 AM UTC-4, Deon Moolman wrote: > > Hey all, > > I'm having some pain with atoms and dereferencing nil - mostly around my > functions sometimes returning an atom and other times nil - I don't really > want to create a special 'nil' atom and do the bits for returning that and > I don't want to be checking nils absolutely everywhere when nil-punning > works perfectly otherwise, so I was wondering what the pitfalls of this > approach would be? > > (extend-type nil IDeref > (-deref [_] nil)) > > Effectively, make @nil nil-pun to nil. makes sense to me? > > Cheers, > - Deon > > -- 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.
