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How to get the pointer of an element from a slice using foreach?
Aug 10
ryuukk_
Aug 12
ryuukk_
August 10
Gravatar of ryuukk_Posted by ryuukk_Reply
ryuukk_
Gravatar of ryuukk_


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Let's pretend i have this code:


Stuff[] mystuff;

foreach (item; mystuff)
{
}

How do i get a pointer?

I can get a reference if i prefix item with ref, but i need a pointer specifically, it can't be impossible, can it?

I could do:

foreach (i, item; mystuff)
{
    auto ptr = &mystuff[i]
}

But this is slow, now does bound checking twice..

I can also fall back to using a C loop, but i'd rather use D for loop

If not possible, why? and what does it take to add support for it in the compiler?

August 11
Gravatar of Richard (Rikki) Andrew CattermolePosted by Richard (Rikki) Andrew Cattermole
in reply to ryuukk_		Reply
Richard (Rikki) Andrew Cattermole
Gravatar of Richard (Rikki) Andrew Cattermole
Posted in reply to ryuukk_


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On 11/08/2023 10:35 AM, ryuukk_ wrote:
> I can get a reference if i prefix |item| with |ref|, but i need a pointer specifically, it can't be impossible, can it?

You're over thinking it. A variable that is a ``ref`` is a pointer with syntax niceties.

```d
void func(ref int val) {
	int* ptr = &val;
}
```
August 12
Gravatar of ryuukk_Posted by ryuukk_
in reply to Richard (Rikki) Andrew Cattermole		Reply
ryuukk_
Gravatar of ryuukk_
Posted in reply to Richard (Rikki) Andrew Cattermole


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On Friday, 11 August 2023 at 04:38:11 UTC, Richard (Rikki) Andrew Cattermole wrote:
> On 11/08/2023 10:35 AM, ryuukk_ wrote:
>> I can get a reference if i prefix |item| with |ref|, but i need a pointer specifically, it can't be impossible, can it?
>
> You're over thinking it. A variable that is a ``ref`` is a pointer with syntax niceties.
>
> ```d
> void func(ref int val) {
> 	int* ptr = &val;
> }
> ```

Ohhh i didn't know this was possible, thanks!!