Re: [boost] variant2 never empty guarantees

Subject: Re: [boost] variant2 never empty guarantees
From: Gavin Lambert (gavinl_at_[hidden])
Date: 2017-06-12 00:30:11

On 9/06/2017 19:43, Andrzej Krzemienski wrote:
> It is funny that you should say that. I remember I wanted at some point to
> test one of Boost's state machines in my toy projects, and I had the exact
> opposite expectation: when the the new state B was being initialized I
> wanted to be able to still access the previous state A, to steal (move)
> some data from it.

Perhaps we had a similar experience then.  I remember running into a 
problem when perfect forwarding was added to a state machine transition 
method, because it ended up trying to move some data of the prior state 
after it had been destroyed (it was explicitly destroying the prior 
state and then forwarding the parameters to the constructor of the new 
state, in that order).