My Problem:

--- (https://run.dlang.io/is/CfLscj)
import std.container.array;
import std.traits;

struct Test
{
   Test[] t;
}

struct Test2
{
   Array!Test2 t;
}

int main()
{
	return FieldTypeTuple!Test.length + FieldTypeTuple!Test2;
}
---

I've found https://issues.dlang.org/show_bug.cgi?id=19407 but I am not using separate compilation, just `dmd test.d`.

I want to have a tree structure like

---
struct S
{
    S[] children;
}
---

but I do not want to rely on the GC and thus wanted to use a custom array type. What's the best way to do this?

On Thursday, 31 October 2019 at 12:29:28 UTC, Tobias Pankrath wrote:
> My Problem:
>
> --- (https://run.dlang.io/is/CfLscj)
> import std.container.array;
> import std.traits;
>
> struct Test
> {
>    Test[] t;
> }
>
> struct Test2
> {
>    Array!Test2 t;
> }
>
> int main()
> {
> 	return FieldTypeTuple!Test.length + FieldTypeTuple!Test2;
> }
> ---
>
> I've found https://issues.dlang.org/show_bug.cgi?id=19407 but I am not using separate compilation, just `dmd test.d`.
>
> I want to have a tree structure like
>
> ---
> struct S
> {
>     S[] children;
> }
> ---
>
> but I do not want to rely on the GC and thus wanted to use a custom array type. What's the best way to do this?

Try

struct S
{
     S*[] children;
}

because otherwise when you declare the array the compiler has not finished the semantic ana of S.

On Thursday, 31 October 2019 at 12:37:55 UTC, user1234 wrote:
> On Thursday, 31 October 2019 at 12:29:28 UTC, Tobias Pankrath wrote:
>> [...]
>
> Try
>
> struct S
> {
>      S*[] children;
> }
>
> because otherwise when you declare the array the compiler has not finished the semantic ana of S.

so S size is not known while S* size is known as it's a pointer

On Thursday, 31 October 2019 at 12:37:55 UTC, user1234 wrote:
> struct S
> {
>      S*[] children;
> }
>
> because otherwise when you declare the array the compiler has not finished the semantic ana of S.

---
struct Test
{
    Test[] t;
}
---

Works today. Putting pointers into the container (and thus having another indirection) is not an option, though.