[DependencyInjection] Add support for key-type in XmlFileLoader

[fabpot]

Q	A
Feature PR	symfony/symfony#58035
PR author(s)	@alexandre-daubois
Merged in	7.2

We created this issue to not forget to document this new feature. We would really appreciate if you can help us with this task. If you are not sure how to do it, please ask us and we will help you.

To fix this issue, please create a PR against the 7.2 branch in the symfony-docs repository.

Thank you! 😃

[alexandre-daubois]

Help wanted to understand where to add this bit. At first I thought of configuration.rst but it is only about arguments and properties, so I doesn't seem to be the right place.

[javiereguiluz]

At first sight I'd also say that this should be documented in this section where we describe all the possible data types of service arguments: https://symfony.com/doc/current/configuration.html#configuration-parameters

[alexandre-daubois]

That was my first choice also. But we actually only talk about service parameters, not arguments 🤔 Maybe it belongs to https://symfony.com/doc/current/service_container/injection_types.html?