关于MSVC和c++如何处理c++模板代码的差异

我在ACCU (http://accu.org/index.php/journals/1916)上偶然发现了这段代码，并且对通过使用CRTP在c++中应用AOP来完成一个有趣的项目很感兴趣。作者给出的代码如下:

namespace aop
{
template <class A>
class NullAspect
{};
template <template <template <class> class> class Base>
struct Decorate
{
private:
    struct None {};
    template <template <class> class ... Aspects>
    struct Apply;
    template <template <class> class T>
    struct Apply<T>
    {
        template <class E>
        using Type = T<E>;
    };
    template<template < class > class A1, template < class > class ... Aspects>
    struct Apply<A1, Aspects...>
    {
        template <class T>
        using Type = A1<typename Apply<Aspects...>::template Type<T>>; // the errors point to this line and the 'Type' refers to the 'template Type<T>'
    };
public:
    template<template <class> class ... Aspects>
    struct with
    {
        template <class T>
        using AspectsCombination = typename Apply<Aspects...>::template Type<T>;
        typedef AspectsCombination<Base<AspectsCombination>> Type;
    };
};
}

我尝试在Microsoft VS2015中编译它，它给了我以下一组错误:

Error   C2146   syntax error: missing '>' before identifier 'Type'  
Error   C2947   expecting '>' to terminate template-argument-list, found '<'    
Error   C2061   syntax error: identifier 'T'    
Error   C2238   unexpected token(s) preceding ';'   
Error   C1201   unable to continue after syntax error in class template definition  
Error   C2143   syntax error: missing ';' before '}'    
Error   C2238   unexpected token(s) preceding ';'   

我使用了相同的代码，检查了语法并在g++中编译，它编译得很好。我应该注意的两个编译器之间是否存在任何差异?这里的问题是什么，使cl.exe生成这些错误?它们是由于cl.exe如何解析任何基于模板的代码?需要做哪些更改才能使此代码在msvc上工作?

这里是作者提供的test.cpp的完整代码，以帮助您更清楚地了解:

#include <iostream>
#include <cmath>
#include "aop.h"
//#define INHERITING_CTORS  as of g++ 6.4.3, inheriting ctors was not implemented
template <typename _UnderlyingType>
struct Number
{
    template <template <class> class A = aop::NullAspect>
    class Type
    {
    public:
        typedef _UnderlyingType UnderlyingType;
        typedef A<Number::Type<A>> FullType;
        Type(UnderlyingType n)
            : n(n)
        {}
        friend std::ostream& operator<<(std::ostream& out, const Type& number)
        {
            return out << number.n;
        }
    protected:
        UnderlyingType n;
    };
};
template <class A>
class ArithmeticAspect: public A
{
public:
    typedef typename A::FullType FullType;
#ifdef INHERITING_CTORS
    using A::A;
#else
    ArithmeticAspect(typename A::UnderlyingType n)
        : A(n)
    {}
    ArithmeticAspect(const A& a)
        : A(a)
    {}
#endif
    FullType operator+(const FullType& other) const
    {
        FullType tmp(*this);
        return tmp += other;
    }
    FullType operator-(const FullType& other) const
    {
        FullType tmp(*this);
        return tmp -= other;
    }
    FullType operator+=(const FullType& other)
    {
        A::n += other.n;
        return A::n;
    }
    FullType operator-=(const FullType& other)
    {
        A::n -= other.n;
        return A::n;
    }
    // same for *, *=, /, /=
};
template <class A>
class IncrementalAspect: public A
{
public:
    typedef typename A::FullType FullType;
#ifdef INHERITING_CTORS
    using A::A;
#else
    IncrementalAspect(typename A::UnderlyingType n)
        : A(n)
    {}
    IncrementalAspect(const A& a)
        : A(a)
    {}
#endif
    FullType operator++(int)
    {
        FullType tmp(*this);
        operator++();
        return tmp;
    }
    FullType operator++()
    {
        ++A::n;
        return *this;
    }
    FullType operator--(int)
    {
        FullType tmp(*this);
        operator--();
        return tmp;
    }
    FullType operator--()
    {
        --A::n;
        return *this;
    }
};
/*
* Configurable Aspect sumExample
*/
template <unsigned int PRECISION>
struct RoundAspect
{
    template <class A>
    class Type : public A
    {
    public:
        typedef typename A::FullType FullType;
#ifdef INHERITING_CTORS
        using A::A;
#else
        Type(typename A::UnderlyingType n)
            : A(n)
        {}
        Type(const A& a)
            : A(a)
        {}
#endif
        FullType operator+(const FullType& other) const
        {
            return FullType(round(A::operator+(other).n));
        }
    private:
        static float round(float f)
        {
            const unsigned int e = std::pow(10, PRECISION);
            return float(int(f * e)) / e;
        }
    };
};
template <class A>
class LogicalAspect: public A
{
public:
    typedef typename A::FullType FullType;
#ifdef INHERITING_CTORS
    using A::A;
#else
    LogicalAspect(typename A::UnderlyingType n)
        : A(n)
    {}
    LogicalAspect(const A& a)
        : A(a)
    {}
#endif
    bool operator!() const
    {
        return !A::n;
    }
    bool operator&&(const FullType& other) const
    {
        return A::n && other.n;
    }
    bool operator||(const FullType& other) const
    {
        return A::n || other.n;
    }
};
template <class A>
class BitwiseAspect: public A
{
public:
    typedef typename A::FullType FullType;
#ifdef INHERITING_CTORS
    using A::A;
#else
    BitwiseAspect(typename A::UnderlyingType n)
        : A(n)
    {}
    BitwiseAspect(const A& a)
        : A(a)
    {}
#endif
    bool operator~() const
    {
        return ~A::n;
    }
    FullType operator&(const FullType& mask) const
    {
        return A::n & mask.n;
    }
    FullType operator|(const FullType& mask) const
    {
        return A::n | mask.n;
    }
    FullType operator<<(const FullType& bitcount) const
    {
        return A::n << bitcount.n;
    }
    FullType operator>>(const FullType& bitcount) const
    {
        return A::n >> bitcount.n;
    }
    FullType& operator>>=(const FullType& bitcount)
    {
        A::n >>= bitcount.n;
        return *static_cast<FullType*>(this);
    }
};
template <class N>
void sumExample(typename N::UnderlyingType n1, typename N::UnderlyingType n2)
{
    N a(n1);
    N b(n2);
    N c = a + b;
    std::cout << c << std::endl;
}
template <class N>
void orExample(typename N::UnderlyingType n1, typename N::UnderlyingType n2)
{
    N a(n1);
    N b(n2);
    std::cout << (a || b) << std::endl;
}
template <class N>
void bitwiseExample(typename N::UnderlyingType n1, typename N::UnderlyingType n2)
{
    N a(n1);
    N b(n2);
    std::cout << (a + ((b >>= 1) << 3)) << std::endl;
}
int main()
{
    typedef aop::Decorate<Number<unsigned int>::Type>::with<ArithmeticAspect, IncrementalAspect, LogicalAspect, BitwiseAspect>::Type IntegralNumber;
    bitwiseExample<IntegralNumber>(1, 2);
    sumExample<IntegralNumber>(1, 2);
    typedef aop::Decorate<Number<float>::Type>::with<RoundAspect<2>::Type, ArithmeticAspect, LogicalAspect>::Type FloatRoundLogicalNumber;
    orExample<FloatRoundLogicalNumber>(1, 0);
    typedef aop::Decorate<Number<int>::Type>::with<LogicalAspect>::Type IntLogicalNumber;
    orExample<IntLogicalNumber>(1, 0);
    typedef aop::Decorate<Number<float>::Type>::with<RoundAspect<2>::Type, ArithmeticAspect>::Type FloatRoundNumber;
    sumExample<FloatRoundNumber>(1.339, 1.1233);
    return 0;
}