I need to find the version of Mojo:::Util that's installed on one of my servers, so I can submit an issue on the Mojolicious Github repository. I followed the recommendations on How can I find the version of an installed Perl module? mainly:
perl -MMojo::Util\ 9999
The response I got when I ran that was:
Mojo::Util does not define $Mojo::Util::VERSION--version check failed.
BEGIN failed--compilation aborted.
I originally installed Mojo::DOM using CPANM and got Mojo::Util because Mojo::DOM depends on it.
How do I determine the version of an installed Perl module where $VERSION is not defined?
They do not have a version. The version of all modules in the Mojolicious distribution is considered to be equal to the version of Mojolicious (it is a somewhat non-standard distribution). So you would check the version of Mojolicious, depend on a certain version of the Mojolicious module, and pass Mojolicious to cpanm to update the distribution.
perl -MMojolicious\ 9999
Note that Mojolicious also includes a version command:
mojo version
In general, if a module you are using or depending on does not have a version, check or depend instead on the version of the main module of the distribution, which is the module sharing the name of the distribution (with some legacy exceptions like libwww-perl). The distribution of a module can be found on its metacpan page or in the packages index.