On Mon, Sep 1, 2014 at 1:52 AM, <adrian.med...@mail.yu.edu> wrote: > If you don't want to wrap the object in an atom, you can also reify an > object that supports IDeref which returns your object. All reified objects > support IObj out of the box. >
As I said earlier: ... can't deref it since I can't change the functions that will use it > later. And again, later: I can't really pass a list since the first function is expecting the object > I am passing, That was why I was asking how to attach metadata. > > On Sunday, August 31, 2014 4:55:58 AM UTC-4, Atamert Ölçgen wrote: > >> Hi Francis, >> >> >> On Sat, Aug 30, 2014 at 1:34 PM, Francis Avila <fran...@gmail.com> wrote: >> >>> It would probably help if you said more about the source of this >>> atom-holding object. Is it a plain Java class? A deftype/defrecord? Is it >>> final? >>> >> >> It's not an atom-holding object. The only guarantee is that this object >> extends one (or two) of these protocols: http://clecs.muhuk. >> com/api/0.2.1/clecs.world.html >> >> Other than that, it can be anything. A Java class, or a type or a >> record... >> >> >> >>> >>> >>> If you can control the construction of this object and its class is not >>> final, you can subclass it and add an IObj implementation. (Note that most, >>> maybe all clojure ways of creating classes create final classes, so this >>> technique won't work.) The easiest way to subclass is with `proxy`: >>> >>> (defn meta-AtomHolder [atom-value metadata] >>> (proxy [AtomHolderClass clojure.lang.IObj] ;; [superclass, new >>> interfaces] >>> [atom-value] ;; constructor args >>> (meta [] metadata) ;; subclass method >>> (withMeta [newmeta] (meta-AtomHolder newmeta)))) >>> => (var user/meta-AtomHolder) >>> (meta-AtomHolder (atom "x") {}) >>> => #<AtomHolderClass$IObj$40298964 user.proxy$AtomHolderClass$ >>> IObj$40298964@302c28cc> >>> (meta (meta-AtomHolder (atom "x") {})) >>> => {} >>> (meta (with-meta (meta-AtomHolder (atom "x") {}) {:a 1})) >>> => {:a 1} >>> >> >> This is really cool. So I can do (deref (meta-AtomHolder (atom "x") {})) >> and it would return "x", right? >> >> I have actually managed to solve it using vars, had to move things around >> a bit: https://github.com/muhuk/clecs/blob/master/src/clecs/ >> world/check.clj#L73 >> >> >> >>> >>> If the parent class is final or you can't construct the object yourself, >>> you need to delegate method calls from one instance to this object >>> instance. I think this is hard-but-not-impossible in java, but I'm not sure. >>> >>> (Clojurescript has `specify`, which does exactly what you want, but only >>> exists because delegation between instances in javascript is trivial.) >>> >>> On Friday, August 29, 2014 10:16:05 PM UTC-5, Atamert Ölçgen wrote: >>>> >>>> Obviously I can't. >>>> >>>> But I need to add this capability to an object. During testing I attach >>>> meta to this object that contains an atom. Then I pass this object to other >>>> functions, known in runtime. I can't use a dynamic var because all this >>>> happens within a mock function that may be retried and run in different >>>> threads. >>>> >>>> I have seen this: http://stackoverflow.com/questions/20724219/simplest- >>>> possible-clojure-object-that-can-accept-a-primitive-and-metadata but >>>> can't deref it since I can't change the functions that will use it later. >>>> If I wrap this object I need to be able to delegate all of its >>>> functionality to the original object. >>>> >>>> I hope this all is not too vague. The code I'm working on is not online >>>> yet. But it's for clecs (https://github.com/muhuk/clecs/), I'm adding >>>> quickcheck to compare different world implementations. >>>> >>>> >>>> -- >>>> Kind Regards, >>>> Atamert Ölçgen >>>> >>>> -+- >>>> --+ >>>> +++ >>>> >>>> www.muhuk.com >>>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Clojure" group. >>> To post to this group, send email to clo...@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+u...@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+u...@googlegroups.com. >>> >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> >> >> -- >> Kind Regards, >> Atamert Ölçgen >> >> -+- >> --+ >> +++ >> >> www.muhuk.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. > -- Kind Regards, Atamert Ölçgen -+- --+ +++ www.muhuk.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.
