No problem, however this nuance has broader implications than just this code snippet :) If you pass false and nil values to a library and expect them to be processed differently, you may end up with a big surprise.
Luc > The difference between nil and false is really handy in some cases > and for many people removing nil (or keeping not-nil) values from a seq > is not removing falsy values. > > I just wanted to point out the issues that may arise from a blind use of > (filter identity [...]) ;) > > On Friday, October 26, 2012 4:36:16 PM UTC+2, Luc wrote: > > > I avoid making explicit distinctions between false and nil in my code. > > In Clojure a falsy value is either nil or false. > > > > In interop I ensure that null and false when returned in the upper layers > > are made consistent (including Boolean objects set to false). > > > > Too much potential trouble in my opinion to let this slip everywhere in > > your > > code, it's not semantically coherent with Clojure. > > > > Luc P. > > > > > > > Be careful with the (filter identity ...) which will also remove > > "falses" > > > from seqs. > > > (filter identity [nil 2 3 nil false true 4]) > > > => (2 3 true 4) > > > Since (identity false) and (identity nil) returns respectively false and > > > nil they are BOTH rejected by filter. > > > > > > This could do the trick: > > > (filter (comp not nit?) [nil 2 3 nil false true 4]) > > > => (2 3 false true 4) > > > > > > On Wednesday, November 17, 2010 2:37:16 AM UTC+1, Luc wrote: > > > > > > > user=> (time (filter identity [ nil 1 2 nil 4])) > > > > "Elapsed time: 0.053219 msecs" > > > > (1 2 4) > > > > > > > > user=> (time (remove nil? [ nil 1 2 nil 4])) > > > > "Elapsed time: 0.065092 msecs" > > > > (1 2 4) > > > > > > > > Choose the flavor your prefer... > > > > > > > > Luc P. > > > > > > > > Glen Rubin <rubi...@gmail.com <javascript:>> wrote .. > > > > > What is the fastest way to remove nils from a sequence? > > > > > > > > > > I usually use the filter function, but I see there are other > > functions > > > > > like remove that should also do the trick. > > > > > > > > > > -- > > > > > You received this message because you are subscribed to the Google > > > > > Groups "Clojure" group. > > > > > To post to this group, send email to > > > > > clo...@googlegroups.com<javascript:> > > > > > > > Note that posts from new members are moderated - please be patient > > with > > > > your first > > > > > post. > > > > > To unsubscribe from this group, send email to > > > > > clojure+u...@googlegroups.com <javascript:> > > > > > For more options, visit this group at > > > > > http://groups.google.com/group/clojure?hl=en > > > > Luc P. > > > > > > > > ================ > > > > The rabid Muppet > > > > > > > > > > > > > > -- > > > You received this message because you are subscribed to the Google > > > Groups "Clojure" group. > > > To post to this group, send email to clo...@googlegroups.com<javascript:> > > > Note that posts from new members are moderated - please be patient with > > your first post. > > > To unsubscribe from this group, send email to > > > clojure+u...@googlegroups.com <javascript:> > > > For more options, visit this group at > > > http://groups.google.com/group/clojure?hl=en > > -- > > Softaddicts<lprefo...@softaddicts.ca <javascript:>> sent by ibisMail from > > my ipad! > > > > -- > 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 -- Softaddicts<lprefonta...@softaddicts.ca> sent by ibisMail from my ipad! -- 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
