On Sun, May 16, 2010 at 3:23 PM, Eric Niebler <eric@boostpro.com> wrote:
Resending. Is Boost.Typeof actively maintained? I can submit a patch for the first issue below, but decltype support should probably be added by someone who knows the library better.
I'm not sure if Boost.Typeof is being actively maintained, but I agree that the first issue should be fixed. If you have a patch for it that's great. decltype support may introduce some minor backwards compatibility issues.
On 5/11/2010 7:48 AM, Eric Niebler wrote:
1) Some compilers don't support typeof in any form, even emulated. From looking at typeof.hpp, it looks like just #include'ing typeof.hpp on those compilers results in a hard error. I'd like a way to test whether typeof is supported and use it if so, otherwise do something else. How can I do that?
2) I can't find "decltype" by grepping the typeof code. Why doesn't typeof use the decltype keyword on compilers that support it?
I think there are some differences. As I recall, typeof doesn't preserve references whereas decltype does, so existing code could be broken in some situations. But I second you're suggestion of migrating to decltype where available/possible.
And I lied. I have another question. How expensive at compile-time is emulated typeof?
Not sure. I think it may vary depending on whether it's called with a user defined/registered class or a primitive type. Daniel Walker