Without extra assumptions, it's impossible to tell what's supposed to be
an element and what's supposed to be a row. For example, this is ambiguous:
(array ((list 1 2)))
It could be a one-dimensional array containing just '(1 2), or a 1x3
array containing 'list, '1 and '2.
My current "extra assumption" is that "[" means "this is a row", and
anything else means "this is an element". The extra assumption could
also be that everything is quasiquoted, and then the shape of the parens
wouldn't matter.
Neil ⊥
On 11/23/2012 03:35 PM, Robby Findler wrote:
Okay, I can't resist: why not use parens?
On Fri, Nov 23, 2012 at 4:31 PM, Neil Toronto <neil.toro...@gmail.com> wrote:
On 11/23/2012 03:03 PM, Robby Findler wrote:
That [implicitly quasiquoting array data] sounds crazy, man. How about
#:keywords instead?
Like this?
(array #:keywords (list) ((list 1 2)))
Deciding how to print elements would be a problem.
If not, then I
think you're better off just going with identifiers.
I'm trying to avoid them because I find this hard to read:
(array (array-row
(array-row (array-row "00" "01" "02"))
(array-row (array-row "10" "11" "12"))
(array-row (array-row "20" "21" "22"))
(array-row (array-row "30" "31" "32"))))
The keywords get in the way. This isn't an issue with any constructor of
flat data like `list', `vector' and #hash(). With those, your brain can
forget about the names that delimit the data because they're at the
beginning, but `array-row' is interspersed. (It's worse when the data are
different sizes.) Compare with this:
(array [[["00" "01" "02"]]
[["10" "11" "12"]]
[["20" "21" "22"]]
[["30" "31" "32"]]])
I read "this is an array," then a bunch of structured data.
(Alternatively, think of how annoying #hash() would be if you had to type
and read (cons x y) instead of (x . y).)
I didn't mind #() because "#" isn't too intrusive. I don't mind implicit
quasiquoting because most array data are going to be constants, so the
ugliness happens infrequently.
I don't want to be stodgy about this, but I also don't want people thinking,
"Oh, that's hideous" the first time they see an array printed. I'm also
aware that this is dangerously close to bikeshedding... :/
Neil ⊥
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