Попытка скомпилировать этот простой класс:
#include <vector>
struct M
{
// interface
auto begin() -> decltype(identities.begin())
{
return identities.begin();
}
// implementation
private:
std::vector<int> identities;
};
приводит к ошибке:
$ g++-510 where.cpp -std=c++11
where.cpp:57:35: error: ‘struct M’ has no member named ‘identities’
auto begin() ->decltype(this->identities.begin())
^
where.cpp:57:35: error: ‘struct M’ has no member named ‘identities’
$ clang++ where.cpp -std=c++11 -Wall -pedantic -Wextra
where.cpp:57:35: error: no member named 'identities' in 'M'
auto begin() ->decltype(this->identities.begin())
~~~~ ^
Почему decltype
не видит член класса?