On 03/03/2018 21:11, mike via Boost wrote:
I don't claim to understand all the implementation details, so sorry if this is dumb question:
What happened to the idea to encode failure or success in a single bit in the status_code_domain pointer, thus making the check if an operation succeeded trivial even in the type-erased case?
That was a potential workaround for Boost.System to not break existing code. A complete rebuild like <system_error2> doesn't need such hacks. It has a formal empty state for those users who won't risk the cost of a virtual function call. For everybody else, it costs one virtual function call at worst, usually not even that as the compiler will have speculatively inlined the implementation and/or the linker will have implemented the 'final' modifier. Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/