Re: not null

[Colin Paul Gloster <Colin_Paul_Gloster@ACM.org>]

On March 4th, 2009, the following webpage was mentioned on news:comp.lang.ada :

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|"[..]                                                                                      |
|http://qconlondon.com/london-2009/presentation/Null+References:+The+Billion+Dollar+Mistake"|
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It seems that Prof. Hoare has made another mistake, as I note that
webpage contained:
"[..] In recent years, a number of program analysers like PREfix and
PREfast in Microsoft [..] give warnings if there is a risk they may be
non-null. [..]"

Warnings might make sense if there is a risk that they could be null,
but why would a possibility of being non-null instead justify the
terms "warnings" and "risk"?

With kind regards,
Colin Paul Gloucester