Hi all, So in the spirit of exposing my ignorance to the internet :-), I have just been bitten by a bug due to the behaviour of the core libraries which I find really surprising:
(def v [1 2 3]) (conj v 4) => [1 2 3 4] (conj (map identity v) 4) => (4 1 2 3) (conj (remove (constantly false) v) 4) => (4 1 2 3) (conj (filter identity v) 4) => (4 1 2 3) In other words, I was relying on map, remove and filter preserving the semantics (other than laziness) of the structure of the input, give it a vector and you get a vector-like lazy sequence. This turns out not to be the case. Now, I know there is mapv which returns a vector but why isn't there a removev and a filterv etc.? What makes it more onerous for me is the fact conj states that its behaviour differs depending on the concrete type, which is great, but how am I supposed to know which concrete type is returned from map|filter|remove? My assumption was it would be semantically equivalent to the input (i.e. a vector in this case). The reason I have dodged this is because I don't frequently rely on vector semantics but I am surprised this isn't better documented? Is it me? Thanks, Colin -- 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 unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
