1YAML::Syck and YAML.pm 0.60 breaks compatibility with older versions by 2changing the tags that are output for serialized objects. 3 4This was the old way: 5 6 --- !perl/Foo::Bar {} 7 --- !perl/@Baz [] 8 --- !perl/$Quux "" 9 10New way: 11 12 --- !!perl/hash:Foo::Bar {} 13 --- !!perl/array:Baz [] 14 --- !!perl/scalar:Quux "" 15 16* This change was made after discussions with the Python and Ruby 17 implementers to standardize on this form. 18* YAML::Syck was updated at the same time as YAML.pm so that they 19 serialize objects the same way. 20* YAML.pm roundtrips the new format and still parses the old (now 21 deprecated) format. 22* The best strategy is to update to the latest version. 23* There are potential problems if you use YAML for RPC and the server 24 and client versions don't match. 25 26