Hello, "Maciek Godek" <[EMAIL PROTECTED]> writes:
> As I ran into the problem, I quickly came with a workaround: > (define unspecified (if #f #t)) > which allows to define the most basic predicates: > (define (unspecified? x) (eq? x unspecified)) > (define (specified? x) (not (unspecified? x))) > > but I find it kinda surprising that these are not available > by default in the system. They are not documented because they are not... specified. :-) Actually, Guile defines `*unspecified*' and also provides `unspecified?', so all you need to define is `specified?'. Thanks, Ludo'.
