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Re: Questions, loose ends, misprints, etc.

This page is part of the web mail archives of SRFI 83 from before July 7th, 2015. The new archives for SRFI 83 contain all messages, not just those from before July 7th, 2015.



Matthew Flatt wrote:
> At Fri, 2 Dec 2005 08:01:48 -0500 (EST), Andre van Tonder wrote:
>>On Thu, 1 Dec 2005, Matthew Flatt wrote:
>>>Andre wrote:
>>>>- Can I export an unbound identifier?  For example, can I export
>>>>  literals (such as ELSE, UNQUOTE, etc.), or does this not even make
>>>>  sense.
>>>
>>>This doesn't make sense to me, at least. What would it mean?
>>
>>Another example would be SRFI-76 R6RS records, where the <record name> might 
>>not necessarily be bound to anything but should be exportable so clients can write:
>>
>>(type-descriptor <record name>) (syntax)
> 
> It seems to me that the <record name> should be bound --- though
> perhaps to a macro that rejects all attempts to use <record name>
> directly.

I can imagine an implementation that doesn't bind <record name> at all,
but rather extends the type-descriptor syntax to match a literal <record
name>, ie,

(define-syntax type-descriptor
  (syntax-rules (<record-name>)
     ((type-descriptor <record-name>) ,,,)))

But, I think that just brings us back to Andre's original question about
exporting the names of literals.

David