Any methods to make attribute declarable in C++ as well?

[roxk]

Right now the only (popular) feature of midl that requires non-trivial annotation is attribute. Commonly used attribute include:

1. Windows repo's contract
2. Xaml content
3. bindable

Is it possible to declare these in C++ as well without needing to write [[idlgen::attribute("bindable",)]]? Note that C++ attribute is not extensible.

---

Idea

struct based

namespace idlgen
{
template <char const* Property = nullptr>
struct attribute
{
};
}

namespace wux
{
struct bindable_attribute : idlgen::attribute<>
{
};
template<char const* Property>
struct content_property_attribute : idlgen::attribute<Property>
{
};
}

const char property_name[] = "Property";
struct ViewModel : ViewModelT<ViewModel>, bindable_attribute, content_property_attribute<property_name>
{
}

SO says it's possible to use const char* as template parameter. Since we need to support C++17 C++20's std::string-in-template-parameter is not something idlgen can enjoy yet.

[roxk]

It works, but property_name must be defined outside of the class which can leak impl detail/introduce pollution (C++17 doesn't support module yet). Everything "just works" in C++20 though...