https://run.dlang.io/is/SC3Fks

On 10/10/2017 03:36 PM, Simon Bürger wrote:
> I have a static array inside a struct which I would like to be initialized to all-zero like so
> 
>    struct Foo(size_t n)
>    {
>      double[n] bar = ... all zeroes ...
>    }
> 
> (note that the default-initializer of double is nan, and not zero)
> 
> I tried
> 
>    double[n] bar = 0;  // does not compile

Works for me:

----
struct Foo(size_t n)
{
    double[n] bar = 0;
}
void main()
{
    import std.stdio;
    Foo!5 foo;
    writeln(foo.bar); /* prints "[0, 0, 0, 0, 0]" */
}
----

On Tuesday, 10 October 2017 at 14:15:07 UTC, Simon Bürger wrote:
> On Tuesday, 10 October 2017 at 13:48:16 UTC, Andrea Fontana wrote:
>> Maybe:
>>
>> double[n] bar = 0.repeat(n).array;
>
> This works fine, thanks a lot. I would have expected `.array` to return a dynamic array. But apparently the compiler is smart enough to know the length. Even the multi-dimensional case works fine:
>
> double[n][n] bar = 0.repeat(n).array.repeat(n).array;

I hope this is not performance-critical code. The assembly is terrible for such code, at least for LDC, doing a GC allocation, unrolled reset to zero, then memcpying the dynamic array back to the stack: https://godbolt.org/g/uXBN75

`double[n] bar = void; bar[] = 0;` (2 lines, granted) results in a memset.

On Tuesday, 10 October 2017 at 22:00:27 UTC, kinke wrote:
> [...]

Ah sorry, overlooked that it's the initializer for a struct field.