various comments S.H.M.J. Houben 12 Nov 2001 13:21 UTC

Interesting proposal.

But of course lots of remarks:

1. The functionality of multi-dimensional arrays can also
   be provided by nested 1-dimensional arrays. It is unclear
   to me why multi-dimensional arrays are needed at all.
   What is the motivation: efficiency (and if so, explain how
   the proposal is more efficient) or added functionality (and
   if so, give an example of things we can do with SRFI-25 not
   easily done with R5RS vectors).

2. I don't think array-dimensions is a good name. I would expect
   it to return all dimensions in some format, not the number of
   dimensions. Since the procedure returns the number of dimensions,
   what about calling it array-number-of-dimensions ?

3. I don't like the shape format. It is logically a list of pairs:
   why not write it as one: e.g. ((0 4) (0 4)) looks better to me
   than (0 4 0 4). For 0-based arrays the shorthand (4 4)
   could then be used.

4. Apparently arrays are supposed to be disjoint from vectors.
   This could be made more explicit. Also, this means that even
   1-dimensional 0-based arrays are disjoint from vectors?

5. From reading the proposal I understand that () is a valid shape,
   but perhaps this point could be clarified separately.

6. share-array says that a linear procedure must be given, and
   that "a constant term is just a special case". Could it be that
   "affine" is meant instead of "linear"?

7. I would rename build-array to tabulate-array . There is little
   difference, in my mind, between making and building an array.

Greetings,

Stephan

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