Review regular-grid logic in zarr-python

[joshmoore]

IIRC Zarr Python has some clever logic to trim unused portions on the edges. Namely detecting fill value usage and trimming chunks for more efficient storage

AIUI one can still retrieve and set all of the values in that chunk. So it may very well comply with this note. Just wanted to raise in case this text has a different idea in mind

Originally posted by @jakirkham in #330 (comment)

[jbms]

This note is saying that all chunks are the same size, even if partially out of bounds. That is mostly independent of the other storage optimization you mentioned.

[jakirkham]

If we think they are consistent, great. Happy to close