I do not understand copy constructors

[Learner]

On Thursday, 12 August 2021 at 12:22:22 UTC, Tejas wrote:
> On Thursday, 12 August 2021 at 12:19:56 UTC, Tejas wrote:
>> [...]
>
> Works with ```@safe``` as well
>
> Paul was just trying to make that other answer work, you don't 
> have to make copy constructors ```@trusted```

Operations are needed on `other` data, that was the reason for a 
`postblit` in the original case: an `int[]` data array needs to 
be duplicated.