Guideline against unconventional overloads

[Eisenwave]

Should there be a guideline recommending against overloading operators that people almost never anticipate to be overloaded? This would include things like:

• overloading the comma operator
• overloading logical AND and logical OR

There is fairly strong consensus in the community that doing so is questionable at best, and afaik standard libraries aren't all comma-safe either.

[jwakely]

I'd add the unary & to that list.

[cubbimew]

For every reasonable expectation of operator overloading, there is boost.spirit