Re: partial, but instead of args + additional, get additional + args
Hi, Am 22.10.2011 um 20:49 schrieb Sean Corfield: I'm starting to think there's a nice, idiomatic solution lurking somewhere that wouldn't require an extra function... The idiomatic solution is #(f % a1 a2 a3). I'm failing to see the issue with “nice” and “expressive”, but that is most likely just me. 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
Re: partial, but instead of args + additional, get additional + args
On Sun, Oct 23, 2011 at 21:25, Meikel Brandmeyer m...@kotka.de wrote: Hi, Am 22.10.2011 um 20:49 schrieb Sean Corfield: I'm starting to think there's a nice, idiomatic solution lurking somewhere that wouldn't require an extra function... The idiomatic solution is #(f % a1 a2 a3). I'm failing to see the issue with “nice” and “expressive”, but that is most likely just me. I find myself reaching for partial when I could be using #(), I even often find myself rejiggering the argument order of my own functions to make them more useful in combination with partial. But, honestly, I'm not quite sure why I have this preference. The #(...) is arguably more readable since we're shown explicitly where the argument goes, and yet I still find myself reaching for partial and comp when I can make them fit. I mean, I like the fact that partial and comp don't cause yet-another-tiny-class to be generated every time they appear in code. But that doesn't seem like reason enough. Am I just being too clever? // Ben 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
Re: partial, but instead of args + additional, get additional + args
On Sun, Oct 23, 2011 at 1:04 PM, Ben Smith-Mannschott bsmith.o...@gmail.com wrote: On Sun, Oct 23, 2011 at 21:25, Meikel Brandmeyer m...@kotka.de wrote: The idiomatic solution is #(f % a1 a2 a3). I'm failing to see the issue with “nice” and “expressive”, but that is most likely just me. I find myself reaching for partial when I could be using #() I was using #() and (fn..) extensively in my code until I noticed just how many anonymous classes were being generated (we had a scenario where we were repeatedly reloading the Clojure code - deliberately - and of course ended up with thousands of these classes loaded!). Understood it's fine in load-once-and-run scenarios. When I brought this up on IRC, several folks said they felt the comp / partial approach was nicer because it was point-free - as well as not generating new classes (new instances, yes, new classes, no - right?). Since then, I've almost eliminated the use of #() and (fn..) in our code and, whilst more verbose initially in some cases, I'm actually really liking the point-free style and it's letting me see new opportunities for refactoring and simplification that I hadn't seen previously (often triggered by encouraging me to pay more attention to argument ordering so that my functions are more composable). Given Meikel's 2009 blog post, I can understand why he might not agree, but given that we have both - and -, it does seem like we have a 'hole' - comp/partial and - go together but there's no comp/??? to go with - and we have to resort to #(f % a1 a2 a3)... -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Railo Technologies, Inc. -- http://www.getrailo.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- 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: partial, but instead of args + additional, get additional + args
On Sun, Oct 23, 2011 at 23:53, Sean Corfield seancorfi...@gmail.com wrote: On Sun, Oct 23, 2011 at 1:04 PM, Ben Smith-Mannschott bsmith.o...@gmail.com wrote: On Sun, Oct 23, 2011 at 21:25, Meikel Brandmeyer m...@kotka.de wrote: The idiomatic solution is #(f % a1 a2 a3). I'm failing to see the issue with “nice” and “expressive”, but that is most likely just me. I find myself reaching for partial when I could be using #() I was using #() and (fn..) extensively in my code until I noticed just how many anonymous classes were being generated (we had a scenario where we were repeatedly reloading the Clojure code - deliberately - and of course ended up with thousands of these classes loaded!). Understood it's fine in load-once-and-run scenarios. When I brought this up on IRC, several folks said they felt the comp / partial approach was nicer because it was point-free - as well as not generating new classes (new instances, yes, new classes, no - right?). Since then, I've almost eliminated the use of #() and (fn..) in our code and, whilst more verbose initially in some cases, I'm actually really liking the point-free style and it's letting me see new opportunities for refactoring and simplification that I hadn't seen previously (often triggered by encouraging me to pay more attention to argument ordering so that my functions are more composable). Given Meikel's 2009 blog post, I can understand why he might not agree, but given that we have both - and -, it does seem like we have a 'hole' - comp/partial and - go together but there's no comp/??? to go with - and we have to resort to #(f % a1 a2 a3)... I propose partail ;-) While partial fills up the arguments from the front, partail fills up the arguments from the back (the *tail*). Plus, the spellings are so similar that it would cause no end of confusion, particularly for people like me that swap letters every once in a while, even when we don't mean to. Ok, Cute name, but not a good name. Anyone got a better one? // Ben -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Railo Technologies, Inc. -- http://www.getrailo.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- 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
Re: partial, but instead of args + additional, get additional + args
Just take an idea from Haskell (as usual!). Function 'flip' returns a function taking its first two arguments in order opposite the given function: user (defn flip [f] (fn [a2 a1 more] (apply f a1 a2 more))) #'user/flip user (- 10 2 3) 5 user ((flip -) 2 10 3) 5 user ((partial 2000) 1000) false user ((partial (flip ) 2000) 1000) true -- 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: partial, but instead of args + additional, get additional + args
On Sat, Oct 22, 2011 at 8:31 AM, Tyler Perkins thinks.outs...@gmail.com wrote: Just take an idea from Haskell (as usual!). Function 'flip' returns a function taking its first two arguments in order opposite the given function: That works nicely for functions with two arguments but in this situation I tend to have more than two arguments so #(f % a1 a2 a3) is what I'd need. After this and other threads, I'm beginning to think that need is a smell of some sort and it signals that the order of the arguments (to f) is wrong (to make it more amenable to partial application). I'm starting to think there's a nice, idiomatic solution lurking somewhere that wouldn't require an extra function... -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Railo Technologies, Inc. -- http://www.getrailo.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- 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: partial, but instead of args + additional, get additional + args
How about a potentially ugly workaround:
user (defn sum [ {:keys [x y]} ] (+ x y))
#'user/sum
user (sum :x 1 :y 2)
3
user (def inc-sum (partial sum :x 1))
#'user/inc-sum
user (inc-sum :y 1)
2
user (inc-sum :y 2)
3
user
I know this is a trivial example, but I do quite fancy named arguments
and being able to set them explicitly in partial.
U
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partial, but instead of args + additional, get additional + args
Hi guys, I fall out in many situations that I want the partial, but inversed, a simple example: Let's say I wanna all primes bellow 2.000: (take-while (partial 2000) primes) In this case, that's ok, but I don't expressed myself write, I because I had to use the oposite of to create the partial, I wanna do something: (take-while (rpartial 2000) primes) In the case of it's ok because they are reverse of each other, but in some circustances there is no reverse function, and you finish can't be using partial, instead you do like: (take-while #( % 2000) primes) I mean, there is no such function on default that works as reversed arguments partial (appending partial arguments at end instead of beginning)? If it don't, is not a good idea to have one? --- Wilker Lúcio http://about.me/wilkerlucio/bio Kajabi Consultant +55 81 82556600 -- 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: partial, but instead of args + additional, get additional + args
On Thu, Oct 20, 2011 at 8:15 PM, Wilker wilkerlu...@gmail.com wrote: In the case of it's ok because they are reverse of each other, but in some circustances there is no reverse function, and you finish can't be using partial, instead you do like: (take-while #( % 2000) primes) I mean, there is no such function on default that works as reversed arguments partial (appending partial arguments at end instead of beginning)? I was expressing a need for exactly this function the other day on IRC. I jokingly called it 'impartial' :) -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Railo Technologies, Inc. -- http://www.getrailo.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- 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: partial, but instead of args + additional, get additional + args
Hi, Am 21.10.2011 um 06:01 schrieb Sean Corfield: On Thu, Oct 20, 2011 at 8:15 PM, Wilker wilkerlu...@gmail.com wrote: (take-while #( % 2000) primes) I was expressing a need for exactly this function the other day on IRC. I jokingly called it 'impartial' :) What is bad about #( % 2000)? In fact I would probably write the other case as #( 2000 %) instead of using partial. The only advantages of partial are a) that it acts like #(apply 2000 %) (to stay in the example) and b) that it generates one class less compared to #(). 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
Re: partial, but instead of args + additional, get additional + args
Hi Miekel, The main reason is because I feel it is more expressive, and I really love expressive code :) --- Wilker Lúcio http://about.me/wilkerlucio/bio Kajabi Consultant +55 81 82556600 On Thu, Oct 20, 2011 at 9:10 PM, Meikel Brandmeyer m...@kotka.de wrote: Hi, Am 21.10.2011 um 06:01 schrieb Sean Corfield: On Thu, Oct 20, 2011 at 8:15 PM, Wilker wilkerlu...@gmail.com wrote: (take-while #( % 2000) primes) I was expressing a need for exactly this function the other day on IRC. I jokingly called it 'impartial' :) What is bad about #( % 2000)? In fact I would probably write the other case as #( 2000 %) instead of using partial. The only advantages of partial are a) that it acts like #(apply 2000 %) (to stay in the example) and b) that it generates one class less compared to #(). 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
