[D typesystem] What is the type of null?

[Bruno Medeiros]

On 13/10/2010 17:27, retard wrote:
> Tue, 12 Oct 2010 17:41:05 +0200, Simen kjaeraas wrote:
>
>> Justin Johansson<no at spam.com>  wrote:
>>
>>>> The answer to the OP's question is simple: null's type is not
>>>> expressible in D.
>>>
>>> That is a sad observation for a language that purports maturity beyond
>>> the epoch of C/C++/Java et. al.
>>
>> I'm curious - why does null need such a specific type?
>
> It's much easier to write a specification, a compiler, and an automatic
> theorem prover for a language with a sane type system. The types and
> transitions are expressible with simple rules of logic. Now you need ad
> hoc special cases. Nothing else.

It may be true that such would make it easier to write an automatic 
theorem prover, maybe also a specification, but would it really make it 
easier to write a compiler for such a language?
And more importantly, even if it was easier, would the language actually 
be a better and more useful language? Better as in a general-purpose 
programming language.
I suspect not, and Justin's implication that D's inability to accurately 
express the type of null is somehow a severe shortcoming seems to me 
like wacky formal-methods fanboyism or some other similar crazyness...


-- 
Bruno Medeiros - Software Engineer