[plt-scheme] What is the default object writer?

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Sun May 2 18:08:07 EDT 2010

At Sun, 2 May 2010 17:59:28 -0400, Doug Orleans wrote:
> I have a class that implements printable<%>, but I only want to
> customize display, not write.  What should I do in the custom-write
> method?  How do I call the default object writer, i.e., the code that
> prints unreadable values, as described in section 12.7.13?

I don't think there's currently a way to chain to the default
implementation. You just have to pick a `write' format, for now.

> Also, perhaps unrelated, but what exactly does the print-unreadable
> parameter do? [...] it doesn't actually
> say what the difference is between #t and #f.

Good point.

If you set the parameter to #f, then an attempt to print an unreadable
value raises an exception.



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