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Re: No exceptions?

From: Jonathan Leffler <jleffler_at_earthlink.net>
Date: Fri, 30 Jun 2006 06:29:39 GMT
Message-ID: <nx3pg.317$PE1.300@newsread2.news.pas.earthlink.net>


paul c wrote:
> Bob Badour wrote:
> ...

>> The way to avoid exceptions is to treat them as compile-time errors.

>
> I take it you really mean "ONE way to avoid exceptions ...". For one
> thing, I am interested in being able to express "x join y" in advance of
> defining a header for "x" (and I would like to evaluate it as well if
> that is logically possible!).

Don't forget the converse problem - there was a relation y at compile time that was removed before runtime; there's no way to generate a compile time exception for the unexceptionable, but there are not many ways of avoiding a runtime exception if the compile time y had defined attributes (was not a synonym of DEE or DUM). Obviously, you could reinterpret the entire program in the light of what you find at runtime, but then why bother with the compilation in the first place? Even within a single program, you could have a relation y available when it is first interpreted that is dropped by the time the statement referencing it is executed. So, some runtime exceptions are nigh-on unavoidable, I think.

-- 
Jonathan Leffler                   #include <disclaimer.h>
Email: jleffler_at_earthlink.net, jleffler_at_us.ibm.com
Guardian of DBD::Informix v2005.02 -- http://dbi.perl.org/
Received on Fri Jun 30 2006 - 01:29:39 CDT

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