boost python异常处理,Boost.python中的error_already_set做什么，以及如何在Python C API中类似地处理异常...

I have been working on a project where I want to remove the boost dependencies and replace it with the Python C API.

I spent some time understanding the Python C API and I saw this

catch (error_already_set const &)

I read the boost docs but it explains where it is used. But I want to know why it is needed and how can I achieve the same functionality using the native Python C api.

解决方案

Boost throws error_already_set when a Python error has occurred. So if you see code like this:

try {

bp::exec(bp::str("garbage code is garbage"));

} catch (const bp::error_already_set&) {

// your code here to examine Python traceback etc.

}

you'll replace it with:

your_ptr res = PyRun_String("garbage code is garbage");

if (!res) {

// your code here to examine Python traceback etc.

}

In other words, wherever you see catch(error_already_set), there you will likely want to do some error handling using whatever PyObject* or other value is involved to recognize when an error has occurred (and therefore you can examine the traceback, or convert it into a C++ exception).