python - 我应该包括什么内容以进行boost.python扩展？

Question

编辑:意外复制粘贴一行两次。
我正在使用boost和常规C API的组合进行C++ Python扩展，但是我无法对其进行编译。我已阅读以下文档:
documentation from boost.org
documentation from python wiki
Python bindings for C++ medium
这是cpp文件中的代码:

#include <boost/python.hpp>#include <boost/python/make_constructor.hpp>#include <boost/python/detail/api_placeholder.hpp>#include <iostream>#include <string>using namespace std;class TestClass{    TestClass(string msg){        cout << "Created test class object" << endl;        cout << msg;    }};BOOST_PYTHON_MODULE(packet){    class_<TestClass>("TestClass", init<std::string>());}

the makefile:

test: test.cpp
    g++ -Wall -shared -std=c++11 -fPIC -I/usr/include -o test`python3-config --extension-suffix` test.cpp

错误输出:

test.cpp:17:5: error: ‘class_’ was not declared in this scope
     class_<TestClass>("TestClass", init<std::string>());
     ^
test.cpp:17:5: note: suggested alternative:
In file included from /usr/include/boost/python/object_core.hpp:20:0,
                 from /usr/include/boost/python/args.hpp:25,
                 from /usr/include/boost/python.hpp:11,
                 from test.cpp:1:
/usr/include/boost/python/def_visitor.hpp:14:56: note:   ‘boost::python::class_’
 template <class T, class X1, class X2, class X3> class class_;
                                                        ^
test.cpp:17:21: error: expected primary-expression before ‘>’ token
     class_<TestClass>("TestClass", init<std::string>());
                     ^
test.cpp:17:36: error: ‘init’ was not declared in this scope
     class_<TestClass>("TestClass", init<std::string>());
                                    ^
test.cpp:17:36: note: suggested alternative:
In file included from /usr/include/boost/python/class.hpp:20:0,
                 from /usr/include/boost/python.hpp:18,
                 from test.cpp:1:
/usr/include/boost/python/init.hpp:58:7: note:   ‘boost::python::init’
 class init; // forward declaration
       ^
test.cpp:17:52: error: expected primary-expression before ‘>’ token
     class_<TestClass>("TestClass", init<std::string>());
                                                    ^
test.cpp:17:54: error: expected primary-expression before ‘)’ token
     class_<TestClass>("TestClass", init<std::string>());
                                                      ^
make: *** [test] Error 1

我想我已经包含了所有头文件，但是我不确定为什么它说没有在此范围内声明。任何帮助将不胜感激

Answer 1

就像(几乎？)Boost中的所有内容(不是宏)一样，class_在命名空间中，在本例中为boost::python。要么:

在文件顶部(包括之后)添加using namespace boost::python;。

改为引用boost::python::class_。

其他符号也是如此。
这是 shown in the quickstart part of the documentation。对于其余大部分，它们仅显示短代码片段，因此我认为它是隐式的。