Re: FW: Exceptions are too return values!

[S. Alexander Jacobson]

On Thu, 11 Jun 1998, Fergus Henderson wrote:
> > It would make debugging easier if the exception picked was consistent
> > accross implementations.  It doesn't matter which one, but it does matter
> > that it is the same.  (maybe you require that Exceptions implement Ord, 
> > or sort based on the Hashvalue of the constructor)
> 
> I think this would be difficult to implement efficiently.

Why is this difficult to implement efficiently?  If exceptions are strings
(as they appear to be in Simon's initial proposal), then you can sort
alphabetically.  If they have type, then they would be required to  
implement Has_HashValue and the implementation could rely on existential
types to sort.  I am sure there are better ways, but It is not obvious why
the objection to cannonical ordering should be implementation
efficiency...

-Alex-

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S. Alexander Jacobson                   i2x Media  
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