Null references (oh no, not again!)

[Walter Bright]

bearophile wrote:
> Walter Bright:
>> It is not hiding the symptom, it is recognizing the reality that
>> you cannot write perfect software, so to require perfect software
>> *and* depend on it being perfect is a recipe for inevitable
>> disaster.
> 
> This discussion is getting a bit silly. You argue no system is
> perfect, bug exists, and you have to put ways to save the situation
> when a trouble has occurred. What almost everyone else is saying is
> that you are right, but if there are simple ways to avoid a whole
> class of bugs, then it may be positive to consider trying such ways
> out. In Boeing they write redundant code and use redundant CPUs and
> all you want, but they also use very rigorous ways to test things
> before they can fail. You have to attack bugs from every side and
> then be prepared to fail. And still, sometimes it doesn't suffice.

I agree, but I wanted to be sure and stamp out the implicit assumption 
in the antecedent that failure cannot be tolerated in mission critical 
software, because that implies it is possible to write perfect software.