Change ROOTNTuple{Reader,Writer} to RNTuple{Reader,Writer}

[jmcarcell]

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• Change ROOTNTuple{Reader,Writer} to RNTuple{Reader,Writer}

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So it's clear it's RNTuple (ROOT also has NTuples. An alternative would be removing ROOT and having simply RNTuple{Reader, Writer}, I guess when there is an interface it won't matter much.

[tmadlener]

I actually like RNTuple{Reader,Writer} a bit more then with ROOT. I suppose it is sufficiently clear that we talk about the RNTuple from ROOT. However, I am not sure how much work that would create for #522 in the end, so if you want to avoid that I am also happy just keeping ROOTRNTuple.

[jmcarcell]

It's OK, it takes only a moment

[tmadlener]

Thanks. Looks good to me.

Let's clarify during the meetings tomorrow and Wednesday, whether we need some sort of backward compatibility for a migration period, or whether we can just press the button as it is.

[jmcarcell]

It should be quite safe to merge. Probably I'm the only one who has been using these writers and readers...