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February 07, 2006
Question and answer
Here i will ask a question, and then answer it the way I think Walter 
would answer.

I would like to create a dynamic but rectangular array (example not D 
syntax):

<example1>

int[,,,,] array = new int[10,7,5,3,2];
array[x,y,z,w,t] = 100;

</example1>

Question: how or when will this be available in D?

Answer:

But you can already to the same thing in D, just write:

<example2>

int[][][][][] array = new int[][][][10];

for(int i=0; i<10; i++)
{
  array[i].length = 7;
  for(int j=0; j<7; j++)
  {
    array[i][j].length = 5;
    for(int k=0; k<5; k++)
    {
      array[i][j][k].length = 3;
      for(int l=0; l<3; l++)
      {
        array[i][j][k][l].length = 2;
      }
    }
  }
}

and then:

array[x+y*10+z*10*7+w*10*7*5+t*10*7*5*3] = 100; //maybe correct

</example2>

Although i agree that the code in these two examples looks almost 
identical and can hardly imagine why anyone would wan't to write the 
first one :) , there may be people who think the first is just a little 
bit simpler.

Is something like this even a remote posibillity for 2.0 D?
February 07, 2006
Re: Question and answer
Ivan Senji wrote:
> Here i will ask a question, and then answer it the way I think Walter 
> would answer.
> 
> I would like to create a dynamic but rectangular array (example not D 
> syntax):
> 
> <example1>
> 
> int[,,,,] array = new int[10,7,5,3,2];
> array[x,y,z,w,t] = 100;
> 
> </example1>
> 
> Question: how or when will this be available in D?
> 
> Answer:
> 
> But you can already to the same thing in D, just write:
> 
> <example2>
> 
> int[][][][][] array = new int[][][][10];
> 
> for(int i=0; i<10; i++)
> {
>   array[i].length = 7;
>   for(int j=0; j<7; j++)
>   {
>     array[i][j].length = 5;
>     for(int k=0; k<5; k++)
>     {
>       array[i][j][k].length = 3;
>       for(int l=0; l<3; l++)
>       {
>         array[i][j][k][l].length = 2;
>       }
>     }
>   }
> }
> 
> and then:
> 
> array[x+y*10+z*10*7+w*10*7*5+t*10*7*5*3] = 100; //maybe correct
> 
> </example2>
> 
> Although i agree that the code in these two examples looks almost 
> identical and can hardly imagine why anyone would wan't to write the 
> first one :) , there may be people who think the first is just a little 
> bit simpler.
> 
> Is something like this even a remote posibillity for 2.0 D?

I think so. Read
http://homepages.uni-regensburg.de/~nen10015/documents/D-multidimarray.html
Walter said it was a good proposal. It will definitely not be in 1.0 
(even array operations, which are in the spec, will not be in 1.0 AFAIK).
February 07, 2006
Re: Question and answer
Don Clugston wrote:
> I think so. Read
> http://homepages.uni-regensburg.de/~nen10015/documents/D-multidimarray.html
> Walter said it was a good proposal. It will definitely not be in 1.0 
> (even array operations, which are in the spec, will not be in 1.0 AFAIK).

I remember that proposal but it was very long time ago, and it gave hope 
that something will happen, but I think that this is as important as 
implicit template instantiation, especialy for a language that has a lot 
of potential to handle arrays better than most other languages.
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