[fpc-devel] Modifiers...

[Sven Barth]

Am 29.01.2024 um 21:18 schrieb Michael Van Canneyt via fpc-devel:
>
>
> On Mon, 29 Jan 2024, Sven Barth via fpc-devel wrote:
>
>> Am 28.01.2024 um 12:14 schrieb Michael Van Canneyt via fpc-devel:
>>>
>>>
>>>>
>>>> 2)
>>>> Is there, or has there once been?
>>>> (found in the synedit highlighter)
>>>>   final
>>>
>>> final comes after virtual/dynamic. Its supposed to stop you from 
>>> overriding
>>> a method. Which is a bit strange because then you should not declare it
>>> virtual to begin with.
>>
>> A person that overrides virtual methods does not always have control 
>> over whether the method had been declared as virtual.
>
> Hm. That makes no sense at all to me ?
>
> You normally add override only when you know the base class has virtual.
> Otherwise, don't add virtual. The compiler will tell you if it was 
> possible
> or not.

But that's the point: you *have* to add override. It will *always* be a 
virtual method ("reintroduce" doesn't count, because that's essentially 
the same as using a method with a completly different name). It's not in 
the control of the user. With "final" the user has that control.

Especially in application code (*not* library code) this can be useful, 
especially if the compiler generates different code in both cases (as 
said the compiler doesn't need to go through the VMT then if called with 
the real class type which can be important in performance relevant code).

Languages like C++, Java and C# all have these functionality as well and 
only because *you* can't think of a legitimate use for it, doesn't mean 
that no one can.

Regards,
Sven