use Mail::Box::Manager;
 my $mgr    = Mail::Box::Manager->new;
 my $folder = $mgr->open(folder => $ENV{MAIL}, ...);
 print $folder->name;

 # Get the first message.
 print $folder->message(0);

 # Delete the third message
 $folder->message(3)->delete;

 # Get the number of messages in scalar context.
 my $emails = $folder->messages;

 # Iterate over the messages.
 foreach ($folder->messages) {...} # all messages
 foreach (@$folder) {...}          # all messages

 $folder->addMessage(Mail::Box::Message->new(...));