On 12 Feb., 01:34, Timothy Pratley <timothyprat...@gmail.com> wrote: > On 12 February 2010 03:19, Martin Hauner <martin.hau...@gmx.net> wrote: > > > I'm mostly interested if there is anything in my code one would/should > > never do that way. > > Looks excellent, you've aced it!
Thanks :-) > I'd like to discuss switching...You wrote: > > (cond > (empty? rolls) 0 > (strike? rolls) (+ (score-strike rolls) (score-after-strike rolls)) > (spare? rolls) (+ (score-spare rolls) (score-after-frame rolls)) > (more? rolls) (+ (score-frame rolls) (score-after-frame rolls))) > > Which is correct and very readable. > > If I wanted a DRYer expression: > (condp #(%1 %2) rolls > empty? 0 > strike? (+ (score-strike rolls) (score-after-strike rolls)) > spare? (+ (score-spare rolls) (score-after-frame rolls)) > more? (+ (score-frame rolls) (score-after-frame rolls))) > > But the #(%1 %2) is ugly and not immediately obvious how it works. > Would it be any nicer if we defined a function-name? > or made a switchp which hides that part? I have to understand condp step by step. We have (condp pred expr) with (test-expr result-expr) and condp does call (pred test-expr expr). With pred = #(%1 %2), expr = rolls, test-expr = empty? etc.. So it finally calls (empty? rolls). I see, but I have to admit that I prefer the simple cond. At least for now ;-) > Or use a trick: > (condp apply [rolls] > .... > ....) Indeed, works too. Trying to understand that one now.. pred = apply, exp = [rolls], condp calls (apply empty? [rolls]) and apply calls (empty? rolls). I like that better than the anonymous function. Someone suggested to use a (binding) to avoid the repeating rolls parameter. He wasn't sure if it would be ok (learning too). Since I have to change the code to calculate (score) in parallel anyway it may be ok to make rolls thread locale!? > I've found myself faced with this particular DRY vs clear trade-off > and never been sure what to do! > > Regards, > Tim. Thanks Martin -- 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
