On Thu, August 26, 2010 12:49 am, Lorenzo Caminiti wrote:
I am trying to use Boost.ScopeExit parameter binding mechanism to implement Boost.LocalFunction. To do so, I need to use some internal ScopeExit code to detect the type of `this` and bind its value to the local function declaration.
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2) Do you know of a workaround for this problem?
I posted a workaround for this a while back (http://lists.boost.org/Archives/boost/2009/03/149540.php) which used type indexing (where the index for typeof(this) is captured outside of a template parameter list) to avoid specifying 'this' in a template parameter list. The mechanics for the solution came from boost.typeof. However, the 'most preferred/natural syntax' relied on the somewhat rude definition of a function-style macro named 'this' (to support detection of the presence of 'this' as the first element of a preprocessor sequence) which, whilst innocuous, violates 17.4.3.1.1: 'Nor shall such a translation unit define macros for names lexically identical to keywords.' This may not be an issue for localfunction if you are always capturing 'this' or have a distinct interface for it's use in member functions. I have attached my latest version of the patch which still applies fine to 1.44 and, I think, works on cl versions from vc7.1 upwards. You should be able to use the same type index trick in localfunction. The key definition is the function-style macro BOOST_SCOPE_EXIT_TYPEDEF_TYPEOF_THIS(). Regards Adam