On Sat, Oct 13, 2012 at 4:55 PM, Matt Calabrese <rivorus@gmail.com> wrote:
On Sat, Oct 13, 2012 at 5:52 PM, Lorenzo Caminiti <lorcaminiti@gmail.com>wrote:
http://contractpp.svn.sourceforge.net/viewvc/contractpp/trunk/doc/html/contr...
Another minor comment. For associated types and constrained parameters such as:
template< ObjectType T>
I see you are using the syntax
template( typename(ObjectType) T )
I am currently using the following syntax in Boost.Generic:
template( ((ObjectType)) T )
My (Boost.Contract) syntax uses this for a value template parameter named T and of type ObjectType (leaving the double parenthesis a side). So I need the typename prefix in order to distinguish between template template parameters and value template parameters. On this topic, while reading N3351 I was thinking to not support this syntax and use requires instead: template( typename T ) requires( ObjectType<T> ) concept_map (RandomAccessIterator) ( T* ) Because I don't know how to support the following: template( typename(ObjectType) T, typename(MapType<T>) U ) concept_map (RandomAccessIterator) ( T* ) Where U is of constrained by MapType<U, T>. The only way I can think to do this is typename(MapType<mpl::_, T>) U (then it'd be up to Boost.Generic to deal with mpl::_ used this way). Does this use case apply to associated types?
This is for a couple of reasons. First, it's concise and closer to the standard syntax, but also because in the end that syntax should be able to be used for unary concepts whose parameter is not a type, in which case "typename" doesn't really make sense.
Thanks, --Lorenzo