Why logger.error instead of raise

[numpde]

In _validate_child_key_integrity you have logger.error but no raises, is that intentional? The severity is not clear and the source of the issue is hard to locate based on the output.

[rmorshea]

Now that I'm looking at this again, raising an exception saying "Expected children to be passed as a sequence (e.g. list or tuple) instead of a generator" might be better. Ultimately what this log is trying to explain is that, because you passed a generator instead of a sequence, IDOM was not able to validate whether all child elements from the generator have keys.

[rmorshea]

On the other hand this isn't a critical failure. We could also warn instead. If we do this we should log at the appropriate stack level using this utility.

[Archmonger]

Perhaps if we can't validate it we may as well reject it?

IDOM does not support generators. Utilize lists instead.

It's feels more JavaScripty to require lists.