The Rule of Zero, or Six -- Rainer Grimm
Speaking of off-by-six errors...
The Rule of Zero, or Six
by Rainer Grimm
From the article:
The rule of zero, or six, is one of the advanced rules in modern C++. I wrote in my current book "C++ Core Guidelines Explained: Best Practices for Modern C++" about them. Today, I want to quote the relevant parts of my book in this post...

Delving into the "how it works" and "why use it" of std::initializer_list...
A new year, a new wave of standards adoption...
A little less primitive...