Re: [cocci] Merging results from parallel data processing?

Julia Lawall <[email protected]> Sun, 10 May 2026 11:07:50 +0200 (CEST)
Newsgroups fr.inria.cocci
Message-ID <[email protected]>

On Sun, 10 May 2026, Markus Elfring wrote:

> >> How do you think about to point the circumstances out under which this one
> >> would be applied?
> >
> > When the semantic patch requests it.  Please see tests/merge_vars.cocci or
> > merco_vars_python.cocci
>
> Thanks for another hint.
>
> https://gitlab.inria.fr/coccinelle/coccinelle/-/blob/03a1af0a3316ddfc2b54d827b8b9627a841c85c9/tests/merge_vars.cocci
> https://gitlab.inria.fr/coccinelle/coccinelle/-/blob/03a1af0a3316ddfc2b54d827b8b9627a841c85c9/tests/merge_vars_python.cocci

No idea what is the point of these links.

> Do you distinguish “merging” from data concatenation in such code?

No idea what this question means.

You can declare variable in OCaml or Python to be the result of
concatenating the results from the different threads.  There is nothing
more to discuss about it.

It's true that the above tests are overly simplistic.  Maybe
tests/names.cocci would be a better example.  But it doesn't have a python
counterpart.

>
> >> Would you become more interested in the clarification of corresponding case distinctions?
> >
> > There are no case distinctions.
>
> How will such a view evolve further according to the use case “parallel data processing”?

No idea what this means.

>
> >> Do you care for the ordering of generated data anyhow?
> >
> > No.
> I find this feedback strange.
> Data users tend to prefer some information ordering, don't they?

You look at the data and order it however you want.  The user has no
control over what files get handled by what tasks, so it doesn't make
sense for Coccinelle to provide any ordering guarantees.

julia