safe-bool-idiom – Tarik Billa

Are there cases where a typedef is absolutely necessary?

September 14, 2023 by Tarik

Ah, I just remembered the identity meta-function. It is possible to write operator typename identity<void (Testable::*)() const>::type() const; with the following definition of identity: template <typename T> struct identity { typedef T type; }; You could argue that identity still uses a typedef, but this solution is “good” enough for me.

C++ safe bool wrapper

July 22, 2023 by Tarik

You can achieve this by explicitly deleting all other constructors. struct Bool final { template<class T> Bool(T) = delete; Bool(bool value); };

Is the safe-bool idiom obsolete in C++11?

October 22, 2022 by Tarik

Yes. This is the example for problems with only having implicit user-defined conversions and explicit user-defined conversion operators were practically invented because of this problem and to replace all the safe-bool stuff with something a lot cleaner and more logical.