Neil Jerram escreveu: > 2008/9/2 Han-Wen Nienhuys <[EMAIL PROTECTED]>: >> If you are doing memq? for something you already know to >> somewhere in front of the list [...] > > Why would you do that? In two senses: > > 1. I know memq gives you the tail of the list, but I usually use its > result only as a true/false value Why would run use memq like that in > a situation where you already know that it will give you true? > > 2. It feels unusual to me to have a long list, but in which certain > kinds of values are known always to be near the front. That sounds > like something that should really be represented as two (or more) > separate lists. > > Have you observed this (the current usage of SCM_VALIDATE_LIST) as a > performance problem in practice?
No, but it feels strange to me that a function whose intrinsic function does not require O(n) behavior, does require it in all cases. However, I find Mikael's argument that it complicates programming a lot persuasive. -- Han-Wen Nienhuys - [EMAIL PROTECTED] - http://www.xs4all.nl/~hanwen
