Isn't the C++ "reference" annotation char & x;
tantamount to declaration of a pointer char * x; to whom NULL assignment, as detectable at compile time, is a compile-time error? If so, is that adequately applicable? ________________________________________ From: webkit-dev-boun...@lists.webkit.org [webkit-dev-boun...@lists.webkit.org] On Behalf Of Maciej Stachowiak [...@apple.com] Sent: Tuesday, July 28, 2009 4:19 PM To: Peter Kasting Cc: WebKit Development Subject: Re: [webkit-dev] NeverNull<T> On Jul 28, 2009, at 3:59 PM, Peter Kasting wrote: On Tue, Jul 28, 2009 at 3:55 PM, Oliver Hunt <oli...@apple.com<mailto:oli...@apple.com>> wrote: Personally i like the idea of having type system/compiler enforced null checking. Note that eseidel's proposal is still a runtime check. One could use template specialization to write a class that gives a compile-time error if you try to assign NULL directly to a pointer, but I'm not enough of a template wizard to know if it could be made to catch all types of assignment (e.g. if you could catch that when a NeverNull<Foo> is initialized by an existing Foo*, that existing pointer must not contain NULL). I don't think you can make the C++ type system prevent pointers from having null values without a runtime check. Any raw pointer expression could have a null value and this is not visible at compile time. It might be possible to prevent direct assignment of 0, which would provide at least a little bit of static checking. Regards, Maciej _______________________________________________ webkit-dev mailing list webkit-dev@lists.webkit.org http://lists.webkit.org/mailman/listinfo.cgi/webkit-dev
