AMDG On 02/25/2013 11:30 AM, Fabio Fracassi wrote:
On 2/25/13 6:13 PM, Steven Watanabe wrote: [snip]
First I think I discovered a bug either in your lib or in clang(with libc++) when compiling one of the documentation examples in C++11 mode.
I haven't tested much with clang in C++11 mode. I wasn't able to get libc++ working on Linux. Are you using the latest version: r83101? Also, exactly what version of clang are you using? I'll take a look at this later today.
Just updated to revision 83153 (boost sandbox), The problem remains. I am using Apple LLVM version 4.2 (clang-425.0.24) (based on LLVM 3.2svn) <snip>
I've just committed a fix for this. I just forgot to handle a case inside one clang #ifdef branch.
[snip]
The problem is the way name lookup works. It's clear that draw can't be found in the template definition, since it isn't declared until later on. Argument dependent lookup usually works, but in this case, the only associated namespace is std (from std::ostream) and draw is defined in the global namespace. (Note that the built-in types have no associated namespaces). BOOST_TYPE_ERASURE_FREE will have exactly the same problem. The solution is add declarations of draw for all builtin types /before/ the definition of drawable.
Ok, this works, but makes it impossible to (reliably) define the concept in isolation. Quite a severe limitation. Is there any possibility to overcome this?
This isn't as bad as you might think. It only applies to built in arithmetic types and types in the standard library of which there are a known fixed set. In Christ, Steven Watanabe