Wrapping array of booleans


I am currently working on wrapping an RTK filter which has a bool * property along with a setter. The wrapped filter properly compiles but the method, when called from a Python script, produces an error (something like the method expects a bool *). I call it by passing a standard Python array (like [True, False, True]) as a parameter. Wrapping C arrays works correctly for other data types, such as int * or float *, but seems broken for bool *.

I tried to look at ITK source code in order to figure out how C arrays are wrapped, but I could not understand, and as far as I searched ITK never wraps bool *. I also tried to replace my bool * by a std::vector<bool> and it made the wrapped filter work.

I thus have several questions:

  • According to ITK development guidelines, is it alright to wrap a std::vector<bool> instead of a bool *? (RTK tries to stick as much as possible to ITK guidelines.)
  • Is there something to modify in ITK which would enable bool * to be properly wrapped?
  • Is there any significant difference in wrapping a std::vector instead of a standard C array?

Sorry if the questions seem basic, I am far from being a swig expect.

Thank you very much!


@matt.mccormick can best answer this question, but probably in about two weeks when he gets back to the office.

Not tested, but should be easy to add a couple of lines here:

%array_functions(bool, BArray);
%array_class(bool, BArrayClass);
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Thank you for your kind replies!
I have tried to implement @phcerdan’s solution, and recompiled everything from scratch, but the error message remains identical:
TypeError: in method '...', argument 2 of type 'bool *'

I’m still stuck with this issue, as my understanding of Swig is very limited. Any tip would be greatly appreciated! Thank you very much.