Null references redux

[Ary Borenszweig]

Jeremie Pelletier wrote:
> Ary Borenszweig wrote:
>> Walter Bright wrote:
>>> Denis Koroskin wrote:
>>>  > On Sat, 26 Sep 2009 22:30:58 +0400, Walter Bright
>>>  > <newshound1 at digitalmars.com> wrote:
>>>  >> D has borrowed ideas from many different languages. The trick is to
>>>  >> take the good stuff and avoid their mistakes <g>.
>>>  >
>>>  > How about this one:
>>>  > 
>>> http://sadekdrobi.com/2008/12/22/null-references-the-billion-dollar-mistake/ 
>>>
>>>  >
>>>  >
>>>  > :)
>>>
>>> I think he's wrong.
>>
>> Please, please, please, do some fun little project in Java or C# and 
>> drop the idea of initializing variables whenever you declare them. 
>> Just leave them like this:
>>
>> int i;
>>
>> and then later initialize them when you need them, for example 
>> different values depending on some conditions. Then you'll realize how 
>> powerful is having the compiler stop variables that are not 
>> initialized *in the context of a function, not necessarily in the same 
>> line of their declaration*. It's always a win: you get a compile time 
>> error, you don't have to wait to get an error at runtime.
>>
>> Until you do that, you won't understand what most people are answering 
>> to you.
>>
>> But I know what you'll answer. You'll say "what about pointers?", 
>> "what about ref parameters?", "what about out parameters?", and then 
>> someone will say to you "C# has them", etc, etc.
>>
>> No point disussing non-null variables without also having the compiler 
>> stop uninitialized variables.
> 
> All null values are uninitialized, but not all initializers are null, 
> especially the void initializer.

I don't see your point here. "new Object()" is not a null intiializer 
nor "1"... so?

  You can't always rely on initializers
> in your algorithms, you can always rely on null.

Yes, I can always rely on initializers in my algorithm. I can, if the 
compiler lets me safely initialize them whenever I want, not necessarily 
in the line I declare them.

Just out of curiosity: have you ever programmed in Java or C#?