So basically, this means c++ template meta-programming is no longer pure (i.e. side-effects can happen during meta-programs) right ? If so, this is quite big n

So basically, this means c++ template meta-programming is no longer pure (i.e. side-effects can happen during meta-programs) right ? If so, this is quite big news, similar to when people realised the extent to which SFINAE could be abused. Not exactly sure this is a good thing though. Ironically, I think some of Stroustrup's goals for c++11/14 were to lower the need for complex template wizardry... Well, now we will have it complex AND stateful !