C++ Coding Standards: 101 Rules, Guidelines, and Best Practices

28. Prefer the canonical form of ++ and --. Prefer calling the prefix forms

Summary

If you ++c, also c++: The increment and decrement operators are tricky because each has pre- and postfix forms, with slightly different semantics. Define operator++ and operator-- such that they mimic the behavior of their built-in counterparts. Prefer to call the prefix versions if you don’t need the original value.

Discussion

An ancient joke about C++ was that the language is called C++ and not ++C because the language is improved (incremented), but many people still use it as C (the previous value). Fortunately, the joke is now obsolete, but it’s a helpful illustration for understanding the difference between the two operator forms.

For ++ and --, the postfix ...