Fortran routine for update

[orso82]

I was able to make some progress writing a small test program that uses the fortran conduit API. However, I could not find anything for updating a node with the data from another node.

Am I missing something, or is it just that the fortran API is lagging behind the C++?
https://llnl-conduit.readthedocs.io/en/latest/tutorial_cpp_update.html

Following is a minimal example that reproduces the problem:

program fortran_test
  use conduit_obj
  type(node) n,n2
  n = conduit_node_obj_create()
  n2 = conduit_node_obj_create()
  n2%update(n) !<-- fails
end program fortran_test

[cyrush]

@orso82, yes - it does lag -- I'd be happy to add this and to take a further pass at more support if there are other things you want to try.

[orso82]

Thank you @cyrush that would be great! 👍 At this point I am really in an exploratory phase, but this was a bit of a stopper at this point, and your offer would help me testing the library further.

I guess the FORTRAN interface is not yet actively used in your any of your LLNL projects?

It is not necessary at this point, but have you considered writing up something that automatically generates the FORTRAN interface starting from the C++ one? Just a thought!

[cyrush]

@orso82 we have focused on a subset of conduit features that allow us to get data in from simulation codes -- particularly in the context of the https://github.com/alpine-DAV/ascent project. So we are exercising it but only a small subset.

We do actually have a good tool for C++ to fortran bindings: https://github.com/llnl/shroud

The conduit fortran wrappers pre-date this tool, perhaps I am a bit crazy to continue to hand wrap, but there is a finite (but maybe large) surface area to cover :-).

I'll take a pass later this week to expose more to fortran.

[orso82]

Great! Thank you! I look forward for the updates!

[cyrush]

@orso82 I made it pretty far with exposing more functions, but I still want to write several more tests.
I expect to have a PR merged sometime next week.

[orso82]

Thank you @cyrush ! I appreciate you taking the time. The PR will also be a good example for me to follow, in case in the future I find myself needing to expose more functions ;)

[cyrush]

@orso82, I just merged #426 into conduit master.

It adds several methods to the fortran api (both the non-obj and obj cases)
The set of update methods (update, update_external, etc) are in there.

If you get a chance to try, let me know if you hit any issues.

[orso82]

Great! Thank you @cyrush 👍