Simon Buchan wrote:
Jonathan Turkanis wrote:
Robert Ramey wrote:
I've concluded that the concept of Semantic really isn't formal. Its a narrative description of what someone expects an expression to do.
Right. Coming from mathematical logic it's clear to me that usual concept definitions aren't really formal. I'd call them 'semi-formal'. If you wanted to write a truly formal specification, you'd first have to describe an abstract machine to represent C++ programs and their execution environments, because the C++ standard isn't really formal, either.
Interesting: an 'abstract machine' representing the compiler is almost exactly the informal description used by version of the standard I saw
But it's not defined precisely enoung to be called 'formal' by my standards. Compare it with the definition of abstract state machines (http://www.eecs.umich.edu/gasm/), for example. Note that I'm not criticising the standard (although it certainly has some problems with lack of precision). It would be nice to have a truly formal specification, but in the case of C++ it's probably not realistic. -- Jonathan Turkanis www.kangaroologic.com