Hey, everybody! I'm having Array Problems™. The documentation on arrays says that you can initialize all elements of a rectangular array with the following syntax:

> double[6][3] matrix = 0; // Sets all elements to 0.

However this doesn't appear to work for static initialization:

> static double[6][3] matrix = 0; // Error: cannot implicitly convert expression `0` of type `int` to `double[6][3]`

More confusingly, it *does* work for one-dimensional static arrays:

> static double[6] matrix = 0; // Thumbs up from the compiler.

Is this a bug, or am I missing something? It would be really convenient to be able to statically initialize rectangular arrays in this way. Example: I have a struct that has a member that's a rectangular float array, but I have no way of telling the compiler that I want it default-initialized to all-zeroes (instead of NaNs)!

On Thursday, 29 August 2019 at 15:10:26 UTC, rombankzero wrote:
> [...]
>
> Is this a bug, or am I missing something? It would be really convenient to be able to statically initialize rectangular arrays in this way. Example: I have a struct that has a member that's a rectangular float array, but I have no way of telling the compiler that I want it default-initialized to all-zeroes (instead of NaNs)!

It's a known bug[1].

As a workaround you could use a `static this()`:

static double[6][3] matrix;

static this()
{
    matrix = 0;
}

[1] https://issues.dlang.org/show_bug.cgi?id=19178

On Thursday, 29 August 2019 at 18:11:50 UTC, Les De Ridder wrote:
> It's a known bug[1].
>
> As a workaround you could use a `static this()`:

Or LDC, and GDC probably too.

On Thursday, 29 August 2019 at 18:59:22 UTC, kinke wrote:
> On Thursday, 29 August 2019 at 18:11:50 UTC, Les De Ridder wrote:
>> It's a known bug[1].
>>
>> As a workaround you could use a `static this()`:
>
> Or LDC, and GDC probably too.

Sorry, that was wrt. the linked bugzilla and not this example here. - What does work is `static double[6][3] matrix = [0, 0, 0]`, i.e., initializing each nested 1D array with a scalar 0.

On Thursday, 29 August 2019 at 19:06:04 UTC, kinke wrote:
> Sorry, that was wrt. the linked bugzilla and not this example here. - What does work is `static double[6][3] matrix = [0, 0, 0]`, i.e., initializing each nested 1D array with a scalar 0.

I guess I'll use this workaround, though obviously it becomes more impractical the larger the outermost array dimension is ¯\_(ツ)_/¯