That's not going to work, all the return classes of partial are the same class.
On Fri, Apr 25, 2014 at 5:26 PM, Greg D <gregoire.da...@gmail.com> wrote: > I don't know if this is considered good Clojure, but you could define a > print-method within a macro to set up the normal string representation for > the partial function: > (defmacro partial* [fname arg0 & args] > `(let [pf# (partial ~fname ~arg0 ~@args) > cpf# (class pf#)] > (defmethod print-method cpf# [o# w#] > (if (nil? '~args) > (print-simple (str "(partial " '~fname " " (pr-str ~arg0) ")") w#) > (print-simple (str "(partial " '~fname " " (pr-str ~arg0) ~@(map > #(str " " (pr-str %)) args) ")") w#))) > pf#)) > > A transcript of some quick examples: > user=> (def p6 (partial* + 1 2 3)) > #'user/p6 > user=> p6 > (partial + 1 2 3) > user=> (p6 7) > 13 > user=> (def re-find-foo (partial* re-find #"foo")) > #'user/re-find-foo > user=> re-find-foo > (partial re-find #"foo") > user=> (re-find-foo "abcdefooghi") > "foo" > > > On Friday, April 25, 2014 9:01:37 AM UTC-7, Matthew DeVore wrote: >> >> Hi, >> >> There has been one thing bugging me for a long time that seems worth it >> to fix, and I was wondering if anyone else has had the same problem. I have >> enjoyed using Clojure's REPL and embracing a Clojure-style data model for >> my app, where everything is a glorified map or vector and there are no >> private fields. I even have a simple dump feature that tells me the entire >> state of my app <https://github.com/google/hesokuri> that was >> ridiculously easy to implement, and that takes advantage of the lack of >> black box data structures. >> >> One thing that doesn't really fit in this paradigm is (ironically) >> anonymous functions with closures. For instance, (partial + 42) returns an >> anonymous function, and in the REPL or an app dump, it looks hideous: >> #<core$partial$fn__4228 clojure.core$partial$fn__4228@1ee1dea2> >> >> So I've avoided anonymous functions in my app except when they exist >> transiently, and don't appear in the dump (for instance, in (map #(str % >> "!") foo)). But sometimes I just can't avoid a long-lived anonymous >> function practically. The best solution I've come up with is to transform >> anonymous functions when preparing the application dump. (See the >> implementation<https://github.com/google/hesokuri/blob/b60cb7222cfdd672e394ef6f22b80c94278fe3a0/src/hesokuri/see.clj#L35>) >> This makes (partial + 42) look like this: >> >> {:fn-class clojure.core$partial$fn__4228, >> "arg1" 42, >> "f" {:fn-class clojure.core$_PLUS_}} >> >> Which isn't great (I'd like to have filenames and line numbers for each >> anon fn, and a nicer name for clojure.core/+), but it's a big improvement. >> The function's JVM class and the closured values are revealed. It would be >> nice to implement this natively. Having only passing familiarity with the >> Clojure code base, to solve it I think one could: >> >> - give anonymous functions a .getClosure method which creates a view >> of the closure on-demand >> - (optional) change their .toString implementation to include this >> information >> - add logic to clojure.pprint to use the .getClosure method (I guess >> "(defmethod clojure.pprint/simple-dispatch clojure.lang.AFunction etc...)" >> ?) >> >> Another feature that would go nicely with this is smarter equality >> semantics for anonymous functions, so that any two anonymous functions >> generated at the same point in code with equal closures are equal. This >> means if I have a function like this: >> >> (defn exclaimer [bangs] #(apply str % (repeat bangs "!"))) >> >> then the following would be true: (= (exclaimer 10) (exclaimer 10)), >> making functions behave a lot more like values. I would love to have this >> particular feature too, although I'm having trouble coming up with a >> non-contrived example. >> >> I'd like to hear some thoughts on this. Thanks! >> >> Matt >> >> >> >> -- > 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. 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