[fpc-pascal] Option type

[Sven Barth]

Am 01.06.2021 um 20:20 schrieb denisgolovan via fpc-pascal:
> Hi all
>
> I am trying to implement Option<T> type in FPC.
>
> type
>    generic TOption<T> = record
>      case IsSome:boolean of
>      true: ( some: T );
>      false: ();
>    end;
>
> However fpc just emits errors:
> Error: Type parameters may require initialization/finalization - cannot be used in variant records

You simply can't use managed types in a variant clause and as T could be 
a managed type the compiler does not allow it.

> Could anybody suggest some sane workaround for the problem?

Use Nullable.TNullable<T>.

Regards,
Sven