On Mon, 04 Jul 2011 11:39:39 +0200, Hans Hübner wrote: > On Mon, Jul 4, 2011 at 11:31 AM, Tamas Papp > <tkp...@gmail.com> wrote: >> Why do some CL library functions have :key arguments? > [...] >> but it is a bit cumbersome. I can make my code simpler by relying on >> calls like >> >> (quantiles (map 'vector key vector) quantiles) > > This not only conses "a bit more", it also duplicates traversal efforts > - The original list must be traversed, and the consed-up list of key > values as well. I think it is prudent that the CL library functions > offer ways to reduce consing for cases where "a bit" is too much (and "a > bit" can become a lot if a program operates on long lists).
I understand this. My main question is: why not do this with compiler macros? Is there any reason for this, other than historical? Note that I am not complaining about the standard, I just want to learn the reason for this design choice so that I can take it into account when writing my own libraries. Best, Tamas _______________________________________________ pro mailing list pro@common-lisp.net http://lists.common-lisp.net/cgi-bin/mailman/listinfo/pro
