Mathias Gaunard wrote:
On 10/20/2011 09:43 AM, Robert Ramey wrote:
I realize that this is whole different kettle of fixh than BOOST_STRONG_TYPE or OPAQUE_TYPE. So this might be considered off topic. or maybe not.
How is it not exactly the same thing?
a) BOOST_STRONG_TYPE and OPAQUE_TYPE presumes that the base type is supports all integer operations while what I'm looking for doesn't make that presumption. c) the new "using ..." creates an alias rather than a new type so this is totall different than BOOST_STRONG_TYPE and OPAQUE_TYPE
You want to create a new type that, for all practical purposes, is the same as the original one, but that can be specialized and overloaded on.
correct.
The point of template alias is indeed to create an alias, not a new type. It has nothing to do with a so-called "strong typedef".
lol - that's my point. Confusion arises when one googles C++ opaque type. This raises a number of papers which address the subject but seem to suggest that the "template alias" feature will create a new type. But a careful reading of the latest documents suggest that this is not the case. This is the motivation for my question. Of course one define a macro #define NEW_OPAQUE_TYPE(new_name, current_type) \ struct new_name : public current_type {}; but I haven't really considered all the implications of this in depth. To summarize, I expected to find a new feature in C++0X but found something else - now I'm wondering what I missed. Robert Ramey