Just a heads-up that I intend to propose SRFI 122 to become the standard multidimensional array package of R7RS-large (the alternatives being SRFI 25 and nothing). It'll be voted on as-is, but an upwardly compatible SRFI could replace 122 at a later stage of voting.
I maintain a fork of SRFI 122
https://github.com/gambiteer/srfi-122/
where I've added a few things that were not in the finalized SRFI,
specifically the routines
interval-cartesian-product
array-outer-product
array-assign!
I continue to think about arrays and how to use them. I'd like to get
various implementations and applications of SRFI-122 available (beyond
what I use it for) and when it looks like I don't have anything more to
add I might propose an updated SRFI with the new routines.
In that vein, if anyone would like assistance to modify SRFI-122 to run
in their favorite scheme, or to use SRFI-122 in support of their
application, I'd be glad to help.
Brad