Re: Interesting C++ way to allocate user data (placement new)

[Francesco Abbate <francesco.bbt@...>]

2012/5/16 Gé Weijers <ge@weijers.org>:
> I usually delay setting the metatable until the object is in a defined
> state, which is hard to do with this idiom. If the constructor of the object
> throws a C++ exception and you catch it the "__gc" routine  the metatable
> refers to may call the destructor, which is a bad idea because the
> constructor failed.

I've banned C++ exceptions from gsl shell, the application I'm
currently developing. The reason is that they pose a serious
integration problem, I'm using a C++ library that is itself not
exception safe. In addition I think that C++ exceptions and Lua
setjmp/longjmp are pretty much incompatibles. To be honest the
setjmp/longjmp is also unfriendly to normal C++ stack unwinding but
exceptions just complicate the scenario even more.

If you add, in addition exceptions that can be thrown from
constructors and destructors you may end up with a big headache :-)

No exceptions and your life is simpler. This is the KISS principle I guess :-)

Francesco