> On Jun 6, 2016, at 10:24 PM, Alex Knauth <alexan...@knauth.org> wrote:
>
> If I run this program:
>
> #lang racket
> (set 1 2 3)
>
> It prints out the value:
>
> (set 1 2 3)
>
> That's wonderful! It uses nice constructor-style printing, just like I
> wanted. That was without changing the printing settings from the default
> print mode.
>
> However, if I change DrRacket's printing settings to use constructor-style
> printing instead, I get this:
>
> (immutable-custom-set ...)
>
> The constructor-style printing mode in DrRacket uses `print-convert` from
> `mzlib/pconvert` to do this, and the `racket/set` library already uses
> `gen:custom-write` for constructor-style printing.
>
> Should `racket/set` sets also use a property similar to
> `prop:print-converter` that `print-convert` can recognize and use? Or should
> sets be another case in the implementation of `print-convert`?
Would something like a `prop:constructor-style-printer` property make sense
here? It would imply `prop:custom-write` with a
`make-constructor-style-printer` value, so it would also cooperate with pretty
printing. And anything like `print-convert` that wants to deal with
s-expressions could recognize this property and use it to do the right thing.
> (struct point (x y)
#:property prop:constructor-style-printer
(list
(lambda (p) 'point)
(lambda (p) (list (point-x p) (point-y p)))))
> (print (point 1 2))
(point 1 2)
> (print-convert (point 1 2))
(list 'point 1 2)
> (parameterize ([pretty-print-columns 10])
(pretty-print (point 3000000 4000000)))
(point
3000000
4000000)
Does this seem like something that should be added to `racket/struct` next to
`make-constructor-style-printer`?
> Alex Knauth
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