On 11/24/2012 05:36 PM, Eli Barzilay wrote:
I'm probably missing the problem, which wouldn't be surprising since I
didn't even tried to look up the `array' documentation...
Well, it didn't exist until I pushed it on Saturday night, so looking it
up wouldn't have done you any good. :D
But, there are two things that seem relevant:
1. For just plain vector syntax, you still have quasiquotes do the
usual thing, it only happens that #(...)s are implicitly quoted.
[...]
I... did not know that. Thanks!
2. Alternatively, the last paragraph that you wrote above can also be
easily translated by just replacing "[" with "#(", so the array
macro distinguishes its contents based on that:
-> (define-syntax foo
(syntax-rules ()
[(foo #(x ...)) (list 'array x ...)]
[(foo x) (list 'datum x)]))
-> (foo (+ 1 2))
'(datum 3)
-> (foo #((+ 1 2)))
'(array 3)
It's obviously a trivially simple example, but if you currently
just dispatch on the paren-shape, then using #(...) instead should
work just as well, be more robust, and not introduce the
shape-dependent feature.
Am I missing something?
Nope. This works really well, so thanks for the fantastical idea. I'm
keeping it.
I considered having array data implicitly quoted, like in vector syntax.
With nested data, though, the number of design options grows quickly,
the rules get complicated, and printing becomes a nightmare.
For example, it's common to have arrays of Indexes, or (Vectorof Index),
which would have to print like this with implicit quoting:
(array `#[,'#(0 0) ,'#(0 1)])
Just working out the algorithm to print such a thing made me want to
curl up and whimper.
Neil ⊥
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