This is Perl module Namespace::Dispatch.
INSTALLATION
Namespace::Dispatch installation is straightforward. If your CPAN shell is set up,
you should just be able to do
% cpan Namespace::Dispatch
Download it, unpack it, then build it as per the usual:
% perl Makefile.PL
% make && make test
Then install it:
% make install
DOCUMENTATION
Namespace::Dispatch documentation is available as in POD. So you can do:
% perldoc Namespace::Dispatch
to read the documentation online with your favorite pager.
shelling