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more srfi-12 rationale?
I have some questions with srfi-12, mainly dealing with conditions.
* Why do we need a new condition type, disjoint from other Scheme values,
with 5 new operations, some of which are quite non-trivial? Why can't
we just use standard lists (perhaps association lists)? It seems rather
non-Schemey (non-orthoginal) to me, to add a new data-stype, with new
operations, that is *similar* to existing data types, but which is
designed for one very specific applications (exceptions and handlers).
* What is the purpose of composite conditions?
I'm sure the authors, who have lots of experience as Scheme implementors,
have good reasons for this design. I just don't see it in the srfi.
I also think the word "condition" is a bit of a mis-nomer. I see
nothing conditional about them.
I will also for the record note that I think it is very desirable
that the exception system be implementable on Scheme systems that
do not support full continuations. From my first reading, it
looks like the proposal *does* satisfy this goal.
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