Finding Core Perl Modules
I wasted 15 minutes the other day trying to remember how to do this, so here it is for the future: to find out if and when a perl module got added to the core, you want Richard Clamp's excellent Module::CoreList.
Recent versions have a 'corelist' frontend command, so I typically use that e.g.
$ corelist File::Basename
File::Basename was first released with perl 5
$ corelist warnings
warnings was first released with perl 5.006
$ corelist /^File::Spec/
File::Spec was first released with perl 5.00405
File::Spec::Cygwin was first released with perl 5.006002
File::Spec::Epoc was first released with perl 5.006001
File::Spec::Functions was first released with perl 5.00504
File::Spec::Mac was first released with perl 5.00405
File::Spec::OS2 was first released with perl 5.00405
File::Spec::Unix was first released with perl 5.00405
File::Spec::VMS was first released with perl 5.00405
File::Spec::Win32 was first released with perl 5.00405
$ corelist URI::Escape
URI::Escape was not in CORE (or so I think)
