Re: How to return a reference to structs?

[Ali Çehreli via Digitalmars-d-learn]

On 11/5/21 11:44 AM, kdevel wrote:
> On Thursday, 4 November 2021 at 11:26:30 UTC, Andrey Zherikov wrote:
>> I have the following code example:
>
> [...]
>
>> A[5] a;
>> ulong[] idx = [1,3,4];
>
> [...]
>
>>     return idx.map!(_ => a[_]);
>
> How can one make the type of idx's elements portable (compile with -m32
> to see what the problem is)?
Indexes are typed as size_t, which is ulong for 64-bit and uint for 
32-bit. If idx elements were indeed indexes, it should have been typed 
as size_t:

import std.algorithm;
import std.stdio;

struct A{}

A[5] a;
size_t[] idx = [1,3,4];  // <-- Here

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

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

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

Ali