Name: Anonymous 2011-02-08 17:34
I'll now post code written with some obscure macros whose implementation will never be released.
(define-macro mcond
#:keyword (else =>)
(macro-case
(() #f)
(((t) (e . r) ...) (>> failure-m t (mcond (e . r) ...)))
(((else . t)) (begin . t))
(((p => f) (e . r) ...) (>> failure-m (>>= maybe-m p f) (mcond (e . r) ...)))
(((p . t) (e . r) ...) (>> failure-m (>> maybe-m p (begin . t)) (~ (e . r) ...)))))