Option DUNE_ENABLE_PYTHONBINDINGS not used

It seems to indicate that one would be able to deactivate python (all these env buildings), but it is never used (Only set to OFF if Python is not found. OFF is the default anyway).

I propose to remove it.

BTW what is the recommended way to skip the python (I keep getting troubles...)? -DCMAKE_DISABLE_FIND_PACKAGE_Python3=ON?

I think the idea was that some people might want to use the 7nternal venv but not the bindings. So only bindings are turned off by setting enable bindings to false. At the moment the only way to turn it completely off is as you suggested.

Like I said, I could not find where it is actually used. Can you give me a pointer?

Nevermind. Found it in the topmost CMakeLists.txt

I'm using DUNE_ENABLE_PYTHONBINDING:BOOL=0 a lot, basically in all setups, because I don't use (and cannot use) anything from the bindings. But I might want to use python for something else, so deactivating python is no option.

I think it would be good to be able to enable/disable all three kinds of python support...

(a) just search for python and potentially enable some code to interact with python (e.g. embedding pythoon in C++) (b) enable the venv (c) enable the bindings

(b) and (c) are to some extent orthogonal and even (b) without (a), (b) could have some relevance.

An example of (b) alone could be some python based code generator. Although not implemented yet, I planned to automatically install the python TPMC library, when compiling the dune cut-cell generation code. That would reduce the burdong of installing the TPMC python code and passing the correct location to cmake.

An other future example could be the dune-codegen module, where certain fenics packages are required and could automatically be added to the venv.

But I might want to use python for something else, so deactivating python is no option.

You mean in non-core modules?

yes. In a user-module I might have python + c++ code. The -DCMAKE_DISABLE_FIND_PACKAGE_Python3=ON deactivates python globally, so I cannot even run my own find_package(Python3) anymore.

I don't know what happens if you deactivate python only in a user-module while compiling the core modules with python enabled. Has anyone tries this?

I mentioned this issue in the description of the original python overhaul MR !960 (merged)

I also think it would be better to have a less coarse mechanism to disable part of the python framework. For example, we could have a flag (e.g. DUNE_USE_PYTHON​) which can be one of bindings, dune-env, off. Tthe off needs a bit more work perhaps - basically in the last case FindPython would be used but nothing more. CMAKE_DISABLE_FIND_PACKAGE_Python3 could of course still be used. The default would be bindings but the others can be used instead. This would then replace the old DUNE_ENABLE_PYTHONBINDING.

mentioned in issue #279 (closed)

Closing as it is used.

closed