[fpc-devel] Considerations about observer [was: Free Pascal 2.6.2 rc1]

[Marco van de Voort]

In our previous episode, michael.vancanneyt at wisa.be said:
> > Then Luiz is right on time with his proposal, with the frist release
> > candidate of the first release that contains this feature. If
> > production code already uses it, then the production code writers must
> > have taken a risk for change knowing that this was a not yet released
> > feature.
> 
> It's rather the opposite. This code was developed and has been in use since
> years. I simply integrated the code in the classes unit, making the
> production code simpler.

Yes, and by doing that  you submit it to public scrutiny, risking other
opinions.
 
> Apart from that, I don't see the point in changing it to an interface.

> At some point, there must be an object, and at some point, there is a
> typecast,

You often can't reroot external components, but if they support tcomponent
(and thus Tinterfacedobject), you can add an interface in a child class.

> I can see the speed argument when notifying, but that can be changed by 
> an internal change, without API changes.

As Paul and Vincent correctly state, from the view of the FPC project, the
interface is not yet fixed.