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Re: [Scheme-reports] 6.1 Exceptions needs examples

Andy Wingo scripsit:

> > You could use the sequence (a c d b) i.e. evaluate the test of the cond
> > clause in the dynamic environment of raise and unwind the stack only
> > when the test returns true.  That's arguably "better" as this will call
> > other handlers in the correct environment if the test returns #f.  
> MHO is that this is the correct thing for r7rs to specify.

Wait, wait.  Are you saying that R7RS should be in the business of
specifying the consequences of what happens when call/cc doesn't allow
resumption?  That's a major addition to the spec.

Or are you arguing for a change in the semantics of `guard` across all
systems?  The whole point of `guard` is to supply termination-style
behavior for exceptions.

Only do what only you can do.               John Cowan <cowan@x>
  --Edsger W. Dijkstra's advice
    to a student in search of a thesis

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