This is Perl module Hash::Lazy.

INSTALLATION

Hash::Lazy installation is straightforward. If your CPAN shell is set up,
you should just be able to do

    % cpan Hash::Lazy

Download it, unpack it, then build it as per the usual:

    % perl Makefile.PL
    % make && make test

Then install it:

    % make install

DOCUMENTATION

Hash::Lazy documentation is available as in POD. So you can do:

    % perldoc Hash::Lazy

to read the documentation online with your favorite pager.

Kang-min Liu