TITLE: C++ Comments Coding Conventions

Good comments
=============
Generally, it's best to let the code itself explain what it does, whereas
the comments are there to describe why it's like that. Do not write comments
that don't add to the reader's understanding of what's going on.

XXX comments
============
Oftentimes, when you're in the middle of implementing something and you don't
want to distract on the details that should be implemented or improved in
future, add an XXX comment:

    strcpy_s(params, sizeof(params), GetCommandLine());
    // XXX: allocate dynamically to handle long command lines

For one thing, this tells anyone reading your code that it's still unstable,
and also points out where the known problems are. For another, if you don't
mark the problems now, they'll be a lot harder to find a week or a year from
now, when you're ready to revisit your old code.
