Is there a solid reason for "instantiate" not to be a plain old function too? OK, the namespace the eval takes place in might change, but if that's causing a problem with importing it seems that using (instantiate `MyClass args...) should result in sending it the fully qualified classname, if it's been imported in the namespace containing the call, rendering the eval namespace issue moot.
On the other hand, is eval any faster than .newInstance here? It's actually compiling a short piece of new bytecode and then invoking it. I wouldn't be surprised if it was slower. On Thu, Jul 4, 2013 at 7:31 AM, Robert Stuttaford < [email protected]> wrote: > Looks like the tradeoffs are composability vs avoiding reflection. I > personally would go for the function until performance becomes a concern. > Being able to use it in HOFs is a big deal! > > > On Thursday, July 4, 2013 12:57:32 PM UTC+2, Jim foo.bar wrote: >> >> (defmacro instantiate >> "Returns an instance of the given class. Depending on the argument list will >> invoke the corresponding constructor." >> [cl-name & args] >> `(eval (list 'new ~cl-name ~@args))) >> >> (defn new-instance "Create a new instance of the specified class using >> reflection." >> [^Class c & args] >> (if (empty? args) (.newInstance c) >> (.newInstance >> (.getConstructor c (into-array (map class args))) >> (to-array args)))) >> >> >> any particular preference? >> >> Jim >> >> -- > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to [email protected] > Note that posts from new members are moderated - please be patient with > your first post. > To unsubscribe from this group, send email to > [email protected] > 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 [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to [email protected] Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to [email protected] 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 [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
