bear wrote:

> At this point I have only one question:  For a rank-5
> array, why #5A(...) instead of #A5(...)?

Maybe #A5 is marginally better, but I think compatibility
with the prior art of Common Lisp argues for #5A.  That's
not an overwheming argument, but (I think) tips the scales
in favor of #5A.

More technical argument: What happens with a rank-0 array?
In APL this is equivalent to a scalar, and in any case a
rank-0 array has a single element.  Given the choice
between #A0XXX and #0AXXX, the latter is better since the
former leads to ambiguities.

> I'm thinking about parsers here, where it's easier on
> everybody if tokens differ as soon as possible.

A (non-human) parser handles either just fine - except
for the degenerate rank-0 case.
--
	--Per Bothner
xxxxxx@bothner.com   http://per.bothner.com/