[racket-dev] Transparent Structures in XML Library

From: Doug Williams (m.douglas.williams at gmail.com)
Date: Mon Oct 3 18:17:32 EDT 2011

The main problem I see with transparent structures is that they are also
inherently mutable. Some of the operation provided may well make use of that
- for example removing whitespace. And, internally, it may be that the
structures are created and then filled - as opposed to building the
substructures and then creating the structure. I really haven't looked.

But, in a larger sense, it is what it is. The API provides transparent
structures and there may be code that relies on it. I may even rely on it
somewhere. So, leaving then as transparent is probably the best way to go -
with prop:custom-write properties to limit the resulting print consequence.

Rewriting it could always be Neil T's next project. :)


On Mon, Oct 3, 2011 at 4:06 PM, John Clements <clements at brinckerhoff.org>wrote:

> On Oct 3, 2011, at 3:01 PM, Doug Williams wrote:
> > The fact that transparent structures also print all of their element - in
> this case recursively, ad nauseam - is more of a side effect. In that case,
> I think prop:custom-write properties should be added. I assume any of the
> print limiting options in my case still walk the entire structure and create
> a several tens of megabytes long string just to truncate it.
> I see. I misread your first mail as suggesting that the XML structures
> should not be #:transparent.
> John
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