That makes sense... thanks, Meikel. Maybe my example of + wasn't the best, given its mathematical nature.
Here's my situation: I'm writing some software to analyze some protein datasets, part of which entails generating a Venn diagram of their intersections. Each dataset has a unique name, and my function looks up the data by this name in a database. Right now the function takes a single "&" parameter of "datasets"; you give it as many dataset names as you want, and it gives you the intersection breakdown. Internally, this function just treats "datasets" like the sequence it is. So I guess a better way to state my question would be this: if you only have a function that operates on a sequence of items, and it could be written either as (def foo [& stuff] ... ) or (def foo [stuff] ... ) ;; where 'stuff' is a sequence are there any concerns besides (for lack of a better term) the "ergonomics" of calling such functions that should influence which signature to use? Does that make sense? Thanks, Chris On Mon, Nov 15, 2010 at 2:08 PM, Meikel Brandmeyer <m...@kotka.de> wrote: > Hi, > > Am 15.11.2010 um 17:52 schrieb Chris: > >> If you have a function that needs to treat multiple arguments as a >> group, what forces drive you to represent this as a single sequence >> argument vs. an "&" argument? To give a concrete example, why does >> "+" work like >> >> (+ 1 2 3 4) >> >> instead of >> >> (+ [1 2 3 4]) >> >> Is it performance? Aesthetics? Composability concerns? Not having >> to call "apply" all the time? > > Semantics? > > + is a binary operator. Allowing more arguments is a convenience I guess. The > mathematically honest definition would have arity 2. > > Eg. filter on the other hand acts on a sequence. That's why it is not defined > as (filter even? 1 2 3 4). (See also map for example where apply wouldn't > help.) > > Does this make sense? > > Sincerely > Meikel > > -- > 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 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
