dereferencing null

[Chad J]

On 03/07/2012 10:40 PM, Jonathan M Davis wrote:
> On Wednesday, March 07, 2012 22:36:50 Chad J wrote:
>> On 03/07/2012 10:08 PM, Jonathan M Davis wrote:
>>> On Wednesday, March 07, 2012 20:44:59 Chad J wrote:
>>>> On 03/07/2012 10:21 AM, Steven Schveighoffer wrote:
>>>>> You can use sentinels other than null.
>>>>>
>>>>> -Steve
>>>>
>>>> Example?
>>>
>>> Create an instance of the class which is immutable and represents an
>>> invalid value. You could check whether something is that value with the
>>> is operator, since there's only one of it. You could even make it a
>>> derived class and have all of its functions throw a particular exception
>>> if someone tries to call them.
>>>
>>> - Jonathan M Davis
>>
>> Makes sense.  Awfully labor-intensive though.  Doesn't work well on
>>
>> classes that can't be easily altered.  That is, it violates this:
>>> - Do not modify the implementation of UnreliableResource.  It's not always
>>> possible.
>> But, maybe it can be turned it into a template and made to work for
>> arrays too...
>
> Personally, I'd probably just use null. But if you want a sentinel other than
> null, it's quite feasible.
>
> - Jonathan M Davis

Wait, so you'd use null and then have the program unconditionally crash 
whenever you (inevitably) mess up sentinel logic?