Description:

When programming the Tk manpage, it's almost always a good idea to keep a
reference to the widgets that you created in the interface. Most of the
time, a simple hash is enough; but it is usually wrapped up in methods to
make the hash private to the window object. And of course, those methods
are duplicated in all modules, under a form or another.

Since duplication is bad, this module implements a the Moose manpage role
implementing those methods once and forever. This implies that your class
is using the Moose manpage in order to consume the role.

About the method names
The methods featured in this role begin with '_', that is, they are
following Perl convention of private methods. This is on purpose:
remember that this method is a role, consumed by your class. And you
don't want those methods to be available outside of the window class,
do you?