caselet

[macro] caselet expr args ...

(mac caselet (var expr . args)
  (let ex (afn (args)
            (if (no (cdr args)) 
                (car args)
                `(if (is ,var ',(car args))
                     ,(cadr args)
                     ,(self (cddr args)))))
    `(let ,var ,expr ,(ex args))))