[fpc-pascal] Dynamic arrays using management operators

[Sven Barth]

Nitorami <mneubauer at alice-dsl.net> schrieb am Mi., 6. Juni 2018, 22:39:

> >2) dynamic arrays can index directly into records and write to fields but
> the [] operator overload can’t do this.
>
> I don't understand this, can you provide an example ?
>

With dynamic arrays that contain records you can do this:

=== code begin ===

var
  parr: array of TPoint;
begin
  // init parr
  // ...
  parr[0].x := 42;
end.

=== code end ===

However you can't do that with indexed properties (which is the feature
that Ryan meant) as the value returned by the property getter is merely a
copy and not a reference.
For completeness sake: for primitive types (except ShortString) and
implicit pointer types (classes, interfaces, dynamic arrays, string types
except ShortString) this behavior is not relevant.

Regards,
Sven

>
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