Excess Guts (R: 18+)

Interfacing to the underlying C++ library is of course achieved by an XS module.

The AptPkg module provides a low-level interface to the library which (as far as possible) exposes the C++ API directly.

C++ classes are thinly in Perl XS classes, with methods and members visible as method calls on those classes.

These XS classes are named with the last component in lower-case and prefixed by an underscore: AptPkg::_config for example.

A higher-level, and more Perl-like API is then provided by wrapping those underlying XS classes again by a Perl class, this time with the last component in mixed case (AptPkg::Config for the previous example).