[fpc-devel] [Suggestion] Enumeration range-check intrinsic

[Ondrej Pokorny]

On 06.07.2019 02:10, Martok wrote:
> In that case, unlike what was previously said in this thread, this should simply
> work:
>
> generic function TStreamHelper.ReadEnum<T>(out aEnum: T): Boolean;
> begin
>    if Read(aEnum, SizeOf(aEnum)) <> SizeOf(aEnum) then
>      Exit(False)
>    else begin
>      Result := (Ord(aEnum) >= Ord(Low(T))) and (Ord(aEnum) <= Ord(High(T)));
>    end;
> end;

Ord(aEnum) for invalid enumeration values is undefined ;)

Ondrej