This page is part of the web mail archives of SRFI 60 from before July 7th, 2015. The new archives for SRFI 60 contain all messages, not just those from before July 7th, 2015.
| Date: Sun, 9 Jan 2005 02:31:52 -0800 (PST) | From: bear <bear@xxxxxxxxx> | | On Sun, 9 Jan 2005, Aubrey Jaffer wrote: | | > | From: sebastian.egner@xxxxxxxxxxx | > | 2. When scanning different libraries of bit-twiddling, I had | > | stumbled across an implicit design decision that is worth | > | mentioning because it might swiftly break portability's neck: | > | | > | "What is the value of (LOGAND)?" | > | | > | In my application I define (LOGAND) := 0 because the subsets my | > | >(logand) ==> -1 because (and) ==> #t. | > | >This is also necessitated because logand is associative: | > | >(logand a b) == (logand a (logand b) (logand)) | | I do not understand why (logand) with zero arguments | ought not signal an error. Can you enlighten me? When dealing with variable arity, empty lists can happen.