I am working to get C++ class enum to python enum using swig. I have the following implementation in example.h file.
namespace colors{ enum class Color{ RED = 0, BLUE = 1, GREEN = 2 }; }
My Swig interface file is
%module api %{ #include "example.h" %} %include "example.h"
But after using swig tool the interface provides the following usage
import pywarp_example as impl impl.RED
The question arise here is that is it possible to access enum like below thats the way we use in python?
impl.Color.RED Or impl.Color.RED.value
Unlike your example SWIG 3.0.12 would wrap your enum class example as Color_RED, Color_BLUE, and Color_GREEN. Here's an example that adds some additional Python code to remap that pattern into Color.RED, Color.BLUE, and Color.GREEN:
%pythoncode is added to the Python portion of the SWIG wrapper. After the Python extension loads this code runs. It collects and deletes variables starting with prefix_, renames them without prefix_, then creates a class named prefix with the new variables as class variables.
%module test %inline %{ namespace colors{ enum class Color{ RED = 0, BLUE = 1, GREEN = 2 }; } %} %pythoncode %{ from enum import Enum def redo(prefix): tmpD = {k:v for k,v in globals().items() if k.startswith(prefix + '_')} for k,v in tmpD.items(): del globals()[k] tmpD = {k[len(prefix)+1:]:v for k,v in tmpD.items()} # globals()[prefix] = type(prefix,(),tmpD) # pre-Enum support globals()[prefix] = Enum(prefix,tmpD) redo('Color') del redo # cleaning up the namespace del Enum %}
Example use:
>>> import test >>> dir(test) ['Color', '__builtin__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__', '_newclass', '_object', '_swig_getattr', '_swig_property', '_swig_repr', '_swig_setattr', '_swig_setattr_nondynamic', '_test'] >>> test.Color <enum 'Color'> >>> dir(test.Color) ['BLUE', 'GREEN', 'RED', '__class__', '__doc__', '__members__', '__module__'] >>> test.Color.BLUE <Color.BLUE: 1>
C++ Enum can be converted to python Enum using this script.
%pythoncode %{ from enum import Enum def enum(prefix): tmpD = {k:v for k,v in globals().items() if k.startswith(prefix + '_')} for k,v in tmpD.items(): del globals()[k] tmpD = {k[len(prefix)+1:]:v for k,v in tmpD.items()} globals()[prefix] = Enum(prefix,tmpD) %}
