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Re: [Scheme-reports] Exceptions on JVM [was: Exceptions needs examples]
Michael Montague scripsit:
> For 'guard' to be really useful in real programs, it needs to be
> cheap, particularly for the normal case (no exception raised). The
> implementation in R7RS captures a continuation in the normal case
> and in Foment, capturing continuations is expensive: it requires a
> stack copy.
The point is that on the JVM, stack copies are not possible, so only
downward closures and upward continuations are supported.
But that, he realized, was a foolish John Cowan
thought; as no one knew better than he cowan@x
that the Wall had no other side. http://www.ccil.org/~cowan
--Arthur C. Clarke, "The Wall of Darkness"
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