my $error_messages = MessageLibrary->new({
  file_open_error => sub{"Couldn't open $_[0]: $!"},
  bad_token => sub{"Invalid token $_[0] encountered on line $_[1]"},
  bad_file_format => "Invalid file format",
});
my $status_messages = MessageLibrary->new({
  starting_parse_phase => "Starting parser...",
  generating_results => sub {"Generating results for element $_[0]"},
});

##</code><code>##

print $status_messages->undefined_msg($a_param, $another);