gistfile1.txt

> (define $f (lambda [$x $pat] (match-all x (Multiset Integer) [pat m])))
f
> (define $pat1 <cons $m <cons ,m _>>)
pat1
> (define $pat2 <cons $m <cons ,(- m 1) _>>)
pat2
> (define $x {2 3 3 4 5})
x
> (test (f x pat1))
{3}
> (test (f x pat2))
{3 4 5}