Re: How to return a reference to structs?

[Andrey Zherikov via Digitalmars-d-learn]

On Thursday, 4 November 2021 at 13:03:54 UTC, Paul Backus wrote:
On Thursday, 4 November 2021 at 11:26:30 UTC, Andrey Zherikov 
wrote:
I have the following code example:
```d
struct A{}

A[5] a;
ulong[] idx = [1,3,4];

auto get()
{
    return idx.map!(_ => a[_]);
}

foreach(i; 0 .. a.length)
    write(&a[i], " ");
writeln;

foreach(ref b; get())
    write(&b, " ");
writeln;
```

How can I change `get` function so it returns the references 
to the content in `a`?

Have the lambda return by reference:

```d
auto get()
{
    return idx.map!(ref (i) => a[i]);
}
```

Making this example a bit complex: I want `get` to return 
additional data to the reference. How should I change the lambda 
then?
```d
auto get()
{
    return idx.map!(ref (i) => tuple(a[i], i)); // return ref and 
index for simplicity
}
```