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Re: [Scheme-reports] 4.2.7. Exception Handling

On 05/18/11 15:28, Andy Wingo wrote:

> Are you sure? :-)  The spec notes:
>   "That implicit `cond' expression is evaluated with the continuation
>   and dynamic extent of the `guard' expression"
> and
>   "The final expression in a <cond> clause is in a tail context if the
>   `guard' expression itself is."

Hrm, OK, it looks like that evolved a bit from my original simplistic
proposal! I'll take a look at the wording there and make sure it's as
intended, when I get a moment.

In which case, the re-raise if no clause matches would rely on having
preserved the original dynamic state by keeping a copy of the
continuation of RAISE around. Or, rather, a continuation captured just
within RAISE before the handler is invoked that, if it actually
continues, causes the re-raise - having re-wound the dynamic state...

> Andy


Alaric Snell-Pym

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