English
A version of the eta law for Pi-cons showing that the constructed function equals the original when tested pointwise.
Русский
Версия закона η для Pi-cons: полученная функция равна исходной при точечном тестировании.
LaTeX
$$$\\text{Pi.cons } m a (f\\ a) (\\lambda a' h',\\; f(a')\\; ) = f$$$
Lean4
/-- A helper function for the powerset of a multiset. Given a list `l`, returns a list
of sublists of `l` as multisets. -/
def powersetAux (l : List α) : List (Multiset α) :=
(sublists l).map (↑)