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From: Florian Weimer <fw@deneb.enyo.de>
Newsgroups: comp.lang.ada
Subject: Re: Type safety on wikipedia
Date: Sun, 29 Jan 2006 22:48:36 +0100
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* Larry Kilgallen:

> I gather you are trying to say some people plan to have their programs
> access via a null pointer and then handle an exception.  That seems
> incredibly sloppy.

Sure, but it's still well-defined in terms of language semantics.  The
program does not "go wrong", as required by the rules for type safety.

The null pointer example is actually a good one because it shows that
even if a program is type safe, it is not necessarily correct.  And
Java with its null pointer exception problem shows that a language
with a type system which is believed to be safe can result in
practical problems which other, even unsafe type systems avoid
(cf. C++ references).