Continued fractions in Perl6 (candidate for http://rosettacode.org/wiki/Continued_fraction#Perl6)

continued-fraction.p6

sub infix:<o>(&f, &g) { -> $x { &f(&g($x)) } }
sub continued-fraction(@a, @b)
{
    gather for [\o] (@a.shift + @b.shift / *) xx * {
        take .(Inf)
    }
}
 
say continued-fraction((1, 2 xx *).list, (1 xx *).list)[3];