Python 在向量模板中使用嵌套枚举引用包装结构

这是一天半以前的事了，但还没有收到任何回复，所以我正在一个更普通的论坛上碰碰运气

我一直在尝试各种方法来包装下面的代码，但有不同程度的错误。大量的搜索让我遇到了类似的问题，还有一张优秀的愿望清单，但老实说，我不确定我是否走上了正确的道路

犁头类型。h:

namespace Plow {

    struct JobState {
      enum type {
        INITIALIZE = 0,
        RUNNING = 1,
        FINISHED = 2
      };
    };
    ...
    class JobFilterT {
     public:
      ...
      std::vector<JobState::type>  states;
      ...

cdef extern from "rpc/plow_types.h" namespace "Plow":

    enum JobState_type "Plow::JobState::type":
        INITIALIZE "Plow::JobState::INITIALIZE"
        RUNNING "Plow::JobState::RUNNING"
        FINISHED "Plow::JobState::FINISHED"

    struct JobState:
        JobState_type type
    ...
    cdef cppclass JobFilterT:
        vector[JobState_type] states 

cimport cython

@cython.internal
cdef class _JobState:
    cdef:
        readonly int INITIALIZE 
        readonly int RUNNING 
        readonly int FINISHED 

    def __cinit__(self):
        self.INITIALIZE = JOBSTATE_INITIALIZE
        self.RUNNING = JOBSTATE_RUNNING
        self.FINISHED = JOBSTATE_FINISHED

JobState = _JobState()

我得到一个错误：

src/plow.cpp: In function ‘std::vector<Plow::JobState::type, std::allocator<Plow::JobState::type> > __pyx_convert_vector_from_py_enum__Plow_3a__3a_JobState_3a__3a_type(PyObject*)’:
src/plow.cpp:6688: error: invalid conversion from ‘long int’ to ‘Plow::JobState::type’

src/plow.cpp:在函数“std:：vector uuupyx_convert_vector_from_py_enum_uuuplow_3a_uu3a_JobState_3a_3a_3a_type（PyObject*）”中：
src/plow.cpp:6688:错误：从“long int”到“plow:：JobState:：type”的转换无效

或：

如何正确包装此嵌套枚举

这是否有必要尝试并准确地包装它，或者我是否可以通过其他方式实现访问这些“名称空间”常量的目标？我是否应该完全忽略这些结构，在pyx中定义自己的常量版本，并使用匹配的int值

---

我试图在cython pyx中简单地定义我自己的常量版本，并将所有内容都视为int（

vector[int]states

），但编译器抱怨不知道如何从

int long

转换到

Plow:：JobState:：type

，我终于找到了答案，在尝试了大量令人难以置信的组合之后。这离我问这个问题之前的最后一次尝试不远了

犁头类型。pxd:

namespace Plow {

    struct JobState {
      enum type {
        INITIALIZE = 0,
        RUNNING = 1,
        FINISHED = 2
      };
    };
    ...
    class JobFilterT {
     public:
      ...
      std::vector<JobState::type>  states;
      ...

cdef extern from "rpc/plow_types.h" namespace "Plow":

    enum JobState_type "Plow::JobState::type":
        INITIALIZE "Plow::JobState::INITIALIZE"
        RUNNING "Plow::JobState::RUNNING"
        FINISHED "Plow::JobState::FINISHED"

    struct JobState:
        JobState_type type
    ...
    cdef cppclass JobFilterT:
        vector[JobState_type] states 

cimport cython

@cython.internal
cdef class _JobState:
    cdef:
        readonly int INITIALIZE 
        readonly int RUNNING 
        readonly int FINISHED 

    def __cinit__(self):
        self.INITIALIZE = JOBSTATE_INITIALIZE
        self.RUNNING = JOBSTATE_RUNNING
        self.FINISHED = JOBSTATE_FINISHED

JobState = _JobState()

我需要忘记

JobState

struct，只包装枚举。但我还需要将它们映射到cython中的新名称，以避免与使用类似名称空间技术的其他枚举发生名称冲突

cdef extern from "rpc/plow_types.h" namespace "Plow":

    ctypedef enum JobState_type "Plow::JobState::type":
        JOBSTATE_INITIALIZE "Plow::JobState::INITIALIZE"
        JOBSTATE_RUNNING "Plow::JobState::RUNNING"
        JOBSTATE_FINISHED "Plow::JobState::FINISHED" 

现在我可以在

vector[JobState\u type]

中引用

JobState\u type

。然后，我使用这种方法使我的常量以只读方式在python中可用：

job.pyx:

namespace Plow {

    struct JobState {
      enum type {
        INITIALIZE = 0,
        RUNNING = 1,
        FINISHED = 2
      };
    };
    ...
    class JobFilterT {
     public:
      ...
      std::vector<JobState::type>  states;
      ...

cdef extern from "rpc/plow_types.h" namespace "Plow":

    enum JobState_type "Plow::JobState::type":
        INITIALIZE "Plow::JobState::INITIALIZE"
        RUNNING "Plow::JobState::RUNNING"
        FINISHED "Plow::JobState::FINISHED"

    struct JobState:
        JobState_type type
    ...
    cdef cppclass JobFilterT:
        vector[JobState_type] states 

cimport cython

@cython.internal
cdef class _JobState:
    cdef:
        readonly int INITIALIZE 
        readonly int RUNNING 
        readonly int FINISHED 

    def __cinit__(self):
        self.INITIALIZE = JOBSTATE_INITIALIZE
        self.RUNNING = JOBSTATE_RUNNING
        self.FINISHED = JOBSTATE_FINISHED

JobState = _JobState()

这给了我一个带有只读常量属性的

JobState

的公共实例

当需要从python值列表转换回

向量[JobState\u type]

时，我会这样做：

someList = [JobState.RUNNING]
...
cdef:
    JobState_type i
    vector[JobState_type] vec_states

for i in someList:
    vec_states.push_back(i)

---

是否有理由不使用命名空间？在C++中我正在打包？C++代码位于代码>犁< /COD>命名空间内。谢谢。通过singleton类将枚举值作为只读常量公开的好主意。这对我不起作用。当我做同样的事情时，我的类上的那些属性不再是int。它们属于“getset_描述符”类型。我无法将枚举传递给声明使用该枚举的函数。它抱怨我没有给它一个机会int@eric.frederich，这将继续在我维护的两个不同的代码库中工作。您是否有一个可用的要点，说明您是如何实现它的？另外，因为Python没有枚举类型，所以这种方法实际上并没有给您类型安全性。如您所见，它们被简单地转换为int字段。如果您希望使用Python公开的类型安全枚举，那么您可能必须采用另一种方法，即使用类似于

.value（）

方法的基类类型。然后为每个枚举对其进行子类化。然后可以接受基类作为类型。