On Saturday, 5 January 2019 at 10:52:48 UTC, Russel Winder wrote:
I found the problem and then two minutes later read your email and bingo we have found the problem.
Well done.
Previously I had used File_Ptr* and on this occasion I was using File_Ptr and there was no copy constructor because I have @disable this(this). Except that clearly copying a value is not copying a value in this case. Clearly this situation is what is causing the destructor to be called on an unconstructed value. But I have no idea why.
Could you post a minimised example? Its a bit hard to guess without one.
The question now, of course, is should I have been using File_Ptr instead of File_Ptr* in the first place. I am beginning to think I should have been. More thinking needed.
From the name, File_Ptr sounds like it is wrapping a reference to a resource. So compare with C's FILE/ D's File which is a reference counted wrapper of a FILE*. Would you ever use a File* (or a FILE**)? Probably not, I never have.
