On Sat, Aug 22, 2009 at 2:08 AM, Sigrid <keyd...@gmx.de> wrote: > > Hi Meikel, hi all, > > thanks for the explanation, I think I got it now. I suppose something > in the sentence I quoted led me to think that pattern matching was > "less" in a way than destructuring, whereas in fact it seems to be the > opposite - pattern matching seems to presuppose destructuring if I'm > correct now.
Correct, pattern matching is built using destructuring bind. > > > Still then (regarding "The way that Rich elected to de-couple > destructuring bind from pattern matching was brilliant.") , it is > unclear to me why it was such a good idea not to include pattern > matching, or, to somehow keep them separate... Destructuring is useful all over the place, not just for pattern matching. For example, it is really useful in function parameter vectors. > > > Ciao, > Sigrid > > > > > On 21 Aug., 21:16, Meikel Brandmeyer <m...@kotka.de> wrote: > > Hi, > > > > Am 21.08.2009 um 20:02 schrieb Sigrid: > > > > > Could someone point me to what the difference is? I know pattern > > > matching e.g. from the PLT scheme implementation, and there the > > > pattern matching also provides the binding and destructuring I > > > think...? > > > > The difference is, that in pattern matching you can also specify > > values on the left side. For example in OCaml: > > > > type foo = [ Foo of int ]; > > > > value frobnicate x = > > match x with > > [ Foo 5 -> do_something () > > | Foo 7 -> do_something_else () > > | Foo x -> do_more x ]; > > > > (Please bear with me if I don't remember all the details of the syntax.) > > > > While this is not possible in Clojure: > > > > (let [[x 5 y] [1 2 3]] > > ...) > > > > The five on the left hand side is not allowed. > > > > Hope this helps. > > > > Sincerely > > Meikel > > > > smime.p7s > > 2KAnzeigenHerunterladen > > > --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
