Bruno Medeiros wrote:
On 13/10/2010 17:27, retard wrote:
Tue, 12 Oct 2010 17:41:05 +0200, Simen kjaeraas wrote:
Justin Johansson<n...@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...
AFAIK, N/A is a fairly legit theorem outcome (laws involving infinity,
or integral of sin(x)/x come to mind).
