Why do we have transitive const, again?

[Jason House]

Mehrdad Wrote:

> On 9/23/2011 11:47 AM, Jonathan M Davis wrote:
> > ...You'd have to duplicate functions all over the place... - Jonathan 
> > M Davis 
> 
> Can't you avoid that trivially with templates?

While templates can be used to coerce a lot of similar things together, it's rarely done without good cause. If you want to pass a short into a function accepting ints, you usually won't templatize the function.

Probably more importantly, const getting added to D was a side effect of adding transitive immutability, and transitive immutability was a side effect of multithreading support. Head const and logical const do not exist in D because it was not required for multithreading.

If Walter thought everyone would use templates to join mutable and immutable together, then const would not exist at all in D.