dereferencing null

Jonathan M Davis jmdavisProg at gmx.com
Wed Mar 7 19:40:54 PST 2012


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


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