Re: auxiliary methods like :before and :after for multimethods?
On Jul 28, 2012, at 4:36 PM, Vinzent wrote: > > robert.hooke works fine with multimethods: > > user=> (defmulti foo class) > nil > user=> (defmethod foo :default [x] (str x)) > # > user=> (require '[robert.hooke :refer (add-hook)]) > nil > user=> (add-hook #'foo (fn [f & [x]] (str "K: " (f x > (#) > user=> (foo 42) > "K: 42" > > foo is a plain function now. Oh, right, good point. I've generally used hooks to modify others' multimethods, and so I suppose I've been lucky to always apply the hook after all methods had been registered. - Chas -- 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
Re: auxiliary methods like :before and :after for multimethods?
> robert.hooke works fine with multimethods: > > user=> (defmulti foo class) > nil > user=> (defmethod foo :default [x] (str x)) > # > user=> (require '[robert.hooke :refer (add-hook)]) > nil > user=> (add-hook #'foo (fn [f & [x]] (str "K: " (f x > (#) > user=> (foo 42) > "K: 42" > foo is a plain function now. -- 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
Re: auxiliary methods like :before and :after for multimethods?
On Jul 28, 2012, at 7:02 AM, Ben Smith-Mannschott wrote: > On Fri, Jul 27, 2012 at 9:06 PM, Vinzent wrote: >> robert-hooke actualy doesn't work with multimethods afaik. You can try my >> new library (https://github.com/dnaumov/hooks), but it's alpha (no docs yet, >> sorry). > > (defmulti foo* (fn [args] ...) ...) > (defmethod foo* :x [args]...) > (defmethod foo* :y [args] ...) > > (defn foo [args] > (foo* args)) > > Only foo calls foo*. Everyone else calls foo. Apply hooks to foo. > > http://en.wikipedia.org/wiki/Fundamental_theorem_of_software_engineering > > ;-) > > // Ben robert.hooke works fine with multimethods: user=> (defmulti foo class) nil user=> (defmethod foo :default [x] (str x)) # user=> (require '[robert.hooke :refer (add-hook)]) nil user=> (add-hook #'foo (fn [f & [x]] (str "K: " (f x (#) user=> (foo 42) "K: 42" More interesting still would be the ability to add hooks to particular methods. `defmethod` doesn't define a new var, so that's not generally possible, but you can work around it by defining functions and tying them to multimethods in separate operations: user=> (defmulti twice class) #'user/twice user=> (defn twice-n [n] (* n n)) #'user/twice-n user=> (defn twice-s [s] (str s s)) #'user/twice-s user=> (.addMethod twice Number #'twice-n) # user=> (.addMethod twice String #'twice-s) # user=> (twice 5) 25 user=> (twice "hi") "hihi" user=> (add-hook #'twice-n (fn [f & [n]] (f (dec n (#) user=> (twice 5) 16 These sorts of situations makes me want for an add-method to go along with remove-method and get-method, just to avoid the .addMethod interop form. - Chas -- 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
Re: auxiliary methods like :before and :after for multimethods?
On Fri, Jul 27, 2012 at 9:06 PM, Vinzent wrote: > robert-hooke actualy doesn't work with multimethods afaik. You can try my > new library (https://github.com/dnaumov/hooks), but it's alpha (no docs yet, > sorry). (defmulti foo* (fn [args] ...) ...) (defmethod foo* :x [args]...) (defmethod foo* :y [args] ...) (defn foo [args] (foo* args)) Only foo calls foo*. Everyone else calls foo. Apply hooks to foo. http://en.wikipedia.org/wiki/Fundamental_theorem_of_software_engineering ;-) // Ben > Any suggestions about API is welcome. -- 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
Re: auxiliary methods like :before and :after for multimethods?
Can you elaborate more about how the system should behave? Also, I don't think it's correct to say that "you own the target function" here, since hook applies to the whole defmulti, not to some concrete defmethod, so I don't see any difference between hooks for functions and multimethods in this case. суббота, 28 июля 2012 г., 9:37:57 UTC+6 пользователь George Oliver написал: > > > > On Friday, July 27, 2012 12:06:33 PM UTC-7, Vinzent wrote: >> >> robert-hooke actualy doesn't work with multimethods afaik. You can try my >> new library (https://github.com/dnaumov/hooks), but it's alpha (no docs >> yet, sorry). > > > Yes, from the robert-hooke readme, "Adding hooks to a defmulti is > discouraged as it will make it impossible to add further methods. Hooks are > meant to extend functions you don't control; if you own the target function > there are obviously better ways to change its behaviour.". > > What got me thinking about :before and :after was the question of how to > add a lightweight rules system to an application. Do you think hooks are > appropriate here? > -- 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
Re: auxiliary methods like :before and :after for multimethods?
On Friday, July 27, 2012 12:06:33 PM UTC-7, Vinzent wrote: > > robert-hooke actualy doesn't work with multimethods afaik. You can try my > new library (https://github.com/dnaumov/hooks), but it's alpha (no docs > yet, sorry). Yes, from the robert-hooke readme, "Adding hooks to a defmulti is discouraged as it will make it impossible to add further methods. Hooks are meant to extend functions you don't control; if you own the target function there are obviously better ways to change its behaviour.". What got me thinking about :before and :after was the question of how to add a lightweight rules system to an application. Do you think hooks are appropriate here? -- 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
Re: auxiliary methods like :before and :after for multimethods?
robert-hooke actualy doesn't work with multimethods afaik. You can try my new library (https://github.com/dnaumov/hooks), but it's alpha (no docs yet, sorry). Any suggestions about API is welcome. пятница, 27 июля 2012 г., 3:15:44 UTC+6 пользователь George Oliver написал: > > hi, I'm wondering if anyone has extended multimethods with auxiliary > methods like CL-style :before and :after, and if not what a suitable > substitute might be. > > > thanks, George > -- 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
Re: auxiliary methods like :before and :after for multimethods?
https://github.com/technomancy/robert-hooke/ On Thu, Jul 26, 2012 at 2:15 PM, George Oliver wrote: > hi, I'm wondering if anyone has extended multimethods with auxiliary methods > like CL-style :before and :after, and if not what a suitable substitute > might be. > > > thanks, George > > -- > 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
auxiliary methods like :before and :after for multimethods?
hi, I'm wondering if anyone has extended multimethods with auxiliary methods like CL-style :before and :after, and if not what a suitable substitute might be. thanks, George -- 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
