C++0x decltype and the scope resolution operator
With a class such as Foo:
struct Foo { static const int i = 9; };
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I find that GCC 4.5 will reject the following
Foo f;
int x = decltype(f)::i;
It will work if I use an intermediate typedef, such as:
typedef decltype(f) ftype;
int x = ftype::i;
but I prefer to keep the namespace clean. I thought precedence may be an issue, so I've also tried parentheses, but no luck. Is it impossible as presented, or is there a piece of syntax that can help me?
It is valid C++0x to say decltype(f)::i
. GCC just doesn't support it yet. You can work it around with an identity template
template<typename T> struct identity { typedef T type; };
int x = identity<decltype(f)>::type::i;
identity
is part of the boost::mpl
namespace.
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