魔精:: DOM：做一些字符需要特殊的轉義？

Question

爲什麼media:group沒有工作，雖然在DOM發生？

#!/usr/bin/env perl 
use warnings; 
use 5.12.0; 
use Mojo::UserAgent; 

my $ua = Mojo::UserAgent->new(); 

my $id = 'E7511681ABEA8635'; 
my $url = 'http://gdata.youtube.com/feeds/api/playlists/' . $id . '?v=2'; 
my $tx = $ua->get($url); 

say $tx->res->dom->at('category')->type; 
say $tx->res->dom->at('media:group')->type; 

# category 
# Can't call method "type" on an undefined value at ./perl.pl line 13 

Answer 1

因爲媒體：是命名空間？ 「：集團媒體」