Null references redux

[Denis Koroskin]

On Sun, 27 Sep 2009 02:18:15 +0400, Walter Bright  
<newshound1 at digitalmars.com> wrote:

> Denis Koroskin wrote:
>>> If you disallow null references what would "Object foo;" initialize to  
>>> then?
>> Nothing. It's a compile-time error.
>
> Should:
>
>     int a;
>
> be disallowed, too? If not (and explain why it should behave  
> differently), what about:
>
>     T a;
>
> in generic code?

Functional languages don't distinguish between the two (reference or not).  
We were discussing "non-null by default"-references because it's far less  
radical change to a language that "non-null by default" for all types.

Once again, you are taking code out of the context. It is worthless to  
discuss "int a;" on its own.
I'll try to but the context back and show a few concrete examples (where T  
is a generic type):

void foo()
{
     T t;
}

Results in: error (Unused variable 't').

T foo(bool someCondition)
{
     T t;
     if (someCondition) t = someInitializer();

     return t;
}

Results in: error (Use of potentially unassigned variable 't')

T foo(bool someCondition)
{
     T t;
     if (someCondition) t = someInitializer();
     else t = someOtherInitializer();

     return t;
}

Results in: successful compilation