p6.p6

proto sub infix:<KK>(|)                   { * }
multi sub infix:<KK>(Mu $x = Bool::False) { $x }
multi sub infix:<KK>(Mu \a, &b)           { a ^^ b() }
multi sub infix:<KK>(Mu \a, Mu \b)        { a ^^ b }
multi sub infix:<KK>(+@a) {
    my Mu $a = shift @a;
    while @a {
        my Mu $b := shift @a;
        $b := $b() if $b ~~ Callable;
        next unless $b;
        return Nil if $a;
        $a := $b;
    }
    $a;
}

say Any KK sub {42}