dmd 2.063 beta 5

[Peter Alexander]

On Thursday, 23 May 2013 at 09:05:02 UTC, Don wrote:
> This means that the const variable x has been initialized TWICE!

That's no different from non-const members.

struct Foo { int x = 1; }
Foo f = Foo(2); // f.x is 2

The initialiser is a default value if you don't provide one in 
the constructor. If you don't mark a variable as static then it 
is not static and needs to be initialised like any other member 
variable.


> This new behaviour is counter-intuitive and introduces a 
> horrible inconsistency.

It is exactly what happens in C++ and causes no confusion there.


> This is totally different to what happens with module 
> constructors (you get a compile error if you try to set a const 
> global if it already has an initializer).

In structs/classes, it is not an initialiser, it is a default 
value in case you don't provide a different value.


> As far as I can tell, this new feature exists only to create 
> bugs. No use cases for it have been given. I cannot imagine a 
> case where using this feature would not be a bug.

The use case is simple: to allow non-static const member 
variables.