Well, I don't want to be a beginner for too long, :-) On May 20, 5:19 pm, Kevin Downey <redc...@gmail.com> wrote: > On Sun, May 20, 2012 at 2:13 PM, Warren Lynn <wrn.l...@gmail.com> wrote: > > Maybe for Person/Employee example with very simple functions do not > > need data types, but I don't think that is generally true (isn't > > "defrecord" trying to patching that up?). When I say "need" I am not > > saying you cannot achieve what you want to do without it (just as > > assembly code can do anything), but things will get so flexible (hence > > the lack of pattern) the language will be "powerful" only on paper > > very soon. I am glad Clojure does not seem to be heading that > > direction, but still I think there might be things we can improve on. > > defrecord, deftype, and defprotocol provide extensible low level > abstractions like the kind Clojure is built on. > > As a Clojure programmer you should only need them rarely. > > As a beginner you should never use them. > > > > > > > > > > > On May 20, 4:51 pm, Kevin Downey <redc...@gmail.com> wrote: > >> On Sun, May 20, 2012 at 10:22 AM, Warren Lynn <wrn.l...@gmail.com> wrote: > >> > So from what I read the philosophy of Clojure discourages inheritance > >> > on concrete data types. However, maybe I am too entrenched in my OO > >> > thinking, how do I define a new record type that includes all the data > >> > members of another record type? I am thinking about the classic > >> > Employee/Person example. > > >> Don't make data members. Use maps and multimethods. You don't need > >> types for this. You have data about a thing, keep it has data, > >> suddenly all the functions that work on data structures (select-keys, > >> update-in, clojure.set) all work on your data instead of having your > >> data locked away in a type. > > >> > If I can define a record of Employee with Person's data members > >> > included, even that is not true inheritance (as no protocols of > >> > "Person" will be automatically extended to "Employee"), I need that > >> > for function re-use (so a function working on Person will > >> > automatically work on Employee because Employee is guaranteed to have > >> > all the data members in Person). > > >> > Also, again, maybe I am too OO minded, is there a way inherit another > >> > record type's protocol implementation? That seems to give the best > >> > combination of both worlds (OO and functional), so you can either have > >> > you own very customized combination of data type/protocols, or use the > >> > very common OO pattern. Just like we have both the single-typed > >> > dispatching (which is more OO like and covers a large portion of use > >> > cases), and more advanced multimethods. > > >> > Thanks. > > >> > -- > >> > 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 > > >> -- > >> And what is good, Phaedrus, > >> And what is not good— > >> Need we ask anyone to tell us these things? > > > -- > > 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 > > -- > And what is good, Phaedrus, > And what is not good— > Need we ask anyone to tell us these things?
-- 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
