[NeXus-committee] ill-documented array types

[j.wuttke]

My posting about data types vs array types is still open.

In the meantime I received private communications suggesting
that the ambiguity of data types is a desirable feature since in
some cases one wants to store data of different ranks.

Which is not a satisfactory answer because:

- In order to ground this discussion, we need concrete use cases
   for flexible ranks.

- Array types admit instances of length one. Doesn't this provide
   enough flexibility? Why we need to specify
      scalar_A or array_of_A
   when the latter, sometimes with length 1, can cover all use cases?

- If it is impossible to specify the rank of certain parameters, this
   still doesn't justify to leave the ranks of _all_ parameters unspecified.

At present, the documentation is inconsistent. As the very least,
it must be clearly explained that the rank of data fields is
currently unspecified, and that "type A" can as well mean "array of A".

In the long run, I would suggest to specify the rank of each single data
field unless flexible rank is explicitly requested for specific reasons.

- Joachim