• funog (7/7) Feb 14 2008 Not sure if it's a bug or not : (DMD 2.010)
• Janice Caron (17/18) Feb 14 2008 Why would you want an associative array that you can't modify? I would
• funog (3/7) Feb 15 2008 If it is passed to a function as read-only

funog <funog ifrance.com> writes:

Not sure if it's a bug or not : (DMD 2.010)

class Food{}
const(int[Food]) caa;
const(Food) x = new Food;
x in caa;

Error: cannot implicitly convert expression (x) of type const(Food) to test.Food

Shouldn't x be a const parameter, as it's not going to be modified by the in
operator as far as I know ?

"Janice Caron" <caron800 googlemail.com> writes:

On 15/02/2008, funog <funog ifrance.com> wrote:
  const(int[Food]) caa;

Why would you want an associative array that you can't modify? I would
have thought

    int[const(Food)] caa;

would be a more useful declaration.

But you may well be right that this is a bug. Const correctness hasn't
completely permeated though D yet. Even opEquals() and opCmp() are
still declared as

    int opEquals(Object o)

instead of the const-correct

   const int opEquals(const(Object) o)

So it wouldn't surprise me if opIn() and opIn_r() are also not const correct.

I would like to think that Walter (...when he can find time...) will
soon go through all of the operator overloads and make sure that every
single one of them is const-correct in D2, and that override catches
everything that doesn't follow suit, and that built-in types like AAs
follow const-correct behavior.

funog <funog ifrance.com> writes:

Janice Caron Wrote:

 On 15/02/2008, funog <funog ifrance.com> wrote:
  const(int[Food]) caa;

 
 Why would you want an associative array that you can't modify?

If it is passed to a function as read-only

void foo(const(int[Food]) readOnlyAArray) { ... }