[R6RS] syntax-case semantics

[Anton van Straaten]

I said I was going to post something concise about the syntax-case 
question.  It boils down to this:

SRFI 72's modified hygiene rule appears to address a real 
hygiene-related issue.  If the R6RS syntax-case specification is not 
going to address that issue, we should have a rationale for that.

I can speculate about some practical reasons for not adopting the rule, 
such as backward compatibility, or lack of experience with the rule. 
However, I have some concerns about such reasons.  I don't know if 
there's any more technical rationale, and if there is, I'd like to know 
more about it.

I'm mentioning this now because adopting the rule is likely to have 
secondary consequences for the syntax-case proposal.  For example, it 
seems that having QUASISYNTAX makes the modified rule's extra rigor more 
palatable, but the previous R6RS syntax-case proposals have not included 
QUASISYNTAX.  It might be a good idea to discuss this before a new 
syntax-case proposal is written up.

Anton