c++ - GCC模板问题

Question

Visual Studio 可以很好地编译这段代码，但 gcc 只允许它在没有模板运算符的情况下进行编译。使用模板运算符会出现以下错误:

第 29 行:错误:应为 `;'在“itrValue”之前

class Test
{
  public:

  Test& operator<<(const char* s) {return *this;} // not implemented yet
  Test& operator<<(size_t      s) {return *this;} // not implemented yet

  Test& operator<< (const std::list<const char*>& strList)
  {
    *this << "count=" << strList.size() << "(";

    for (std::list<const char*>::const_iterator itrValue = strList.begin();
         itrValue != strList.end(); ++itrValue)
    {
        *this << " " << *itrValue;
    }

    *this << ")";

    return *this;
  }

  template <class T>
  Test& operator<< (const std::list<T>& listTemplate)
  {
    *this << "count=" << listTemplate.size() << "(";

    // this is line 28, the next line is the offending line
    for (std::list<T>::const_iterator itrValue = listTemplate.begin();
         itrValue != listTemplate.end(); ++itrValue)
    {
        *this << " " << *itrValue;
    }

    *this << ")";

    return *this;
  }
};

Answer 1

GCC 是对的，const_iterator 是一个类型，并且模板依赖于模板运算符<<，你需要告诉编译器它是一个类型而不是变量:

typename std::list<T>::const_iterator