Error C4596 'proto_extends': illegal qualified name in member declaration

Hello,

I have built boost filesystem and system on windows msvc 2017 and then I have included the boost include dir in my project to build my application.
When I build the solution on msvc 2017 15.9.15 I get the following error:

`Error C4596 'proto_extends': illegal qualified name in member declaration fiction e:\development\boost-1.70.0\include\boost\xpressive\regex_primitives.hpp 569 `

Which is related to the macro defined in extends.h

```
#define BOOST_PROTO_EXTENDS_USING_ASSIGN_NON_DEPENDENT(Derived) \
typedef Derived::proto_extends proto_extends; \
using proto_extends::operator =; \
BOOST_PROTO_EXTENDS_COPY_ASSIGN_(Derived, BOOST_PP_EMPTY) \
/**/
```

I have also tried adding Hint files in the solution but it doesn't work.
Is there an error in the typedef?

Thanks for your support.