> If you need `cdr' after `assoc' very often, I'd use a helper procedure like
> this one:
>
> (define (assoc-ref key alist)
>   (and-let* ((entry (assoc key alist)))
>     (cdr entry)))
>
> This way, you don't have any magic `cdr's in your code and you express your
> intent as clearly as possible.  (And choose whatever style you want in the
> body of `assoc-ref'. :))

This breaks the correctnsess of assoc: That #f is always unambigous as
"not found". That’s why I want to preserve the behaviour and only unpack
in the final processing.