The version hashref for a dist includes a new type of entry for corelist modules.

[briandfoy]

In #190, sparrow2009 discovered that perl core has releases of dual-lived modules that are not on CPAN, such as IPC::Cmd 0.92_01. As such, MetaCPAN's API does not know they exist for the IPC-Cmd distro. In the data structure, the versions are stored in $db->{dist}{$dist}{'versions'}, which is an array that has hashrefs as values:

[
    { version => ..., date => ... }
]

I now augment this with data I infer from corelist. I push additional hashrefs for the versions not already represented in the array, and I add a couple more fields to that hashref to distinguish the source:

[
    { version => ..., date => ... }
    {
      version => '0.92_01',
      date      => $perl_release_date,
      perl_version => $first_perl_release,
      dual_lived.    => 1,
    }
]

This shouldn't affect any accesses since these augmented hashrefs since it has the same keys. If you check that there are only two keys as before, or doing some other sort of validation, you might have to adjust that.