[Gambas-user] Problems with controls - text property

[ron]

On Friday 27 April 2007 00:52, Benoit Minisini wrote:
> On vendredi 27 avril 2007, ron wrote:

...........

> >
> >
> > Ron
> >
> 
> Hmm... It is absolutely not that :-)
> 
> The Name property has been implemented for a while.

Many thanks, got bless you :) :) :)
Shame to me, I miss the announcement of it.

> 
> The problem is that Steven didn't understand that if *he* knows that his test 
> is true only for control having the Text property, Gambas does not.
> 
> Gambas uses static typing with virtual dispatching. 
> 
> 'Static typing' means that the class of an object is given by the declaration 
> of the variable that contains its reference.
> 
> 'Virtual dispatching' means that the symbol (method or property) applied to 
> this reference will call the implementation of the true object class, not the 
> class given by the declaration of the variable.
> 
> So if the 'ctrl' variable is declared 'AS Control', then you can only use 
> symbols of the Control class on it.
> 
> If you want Gambas to use dynamic typing, i.e. detects that the Text property 
> exists each time it uses it, then you must declare the 'ctrl' variable 'AS 
> Object'. But this is slower, as each symbol applied to 'ctrl' will need a 
> lookup in the symbol table of the object class.
> 
> I hope I was clear, as it is difficult for me to explain that in English.
> 
> Note that is exactly like C++, with classes having virtual methods only. 
> Except that C++ has no dynamic typing of course.
> 
> Regards,
> 

I do believe I understand.
Your explanation about static and virtual here is for me clear ATM.

Thanks 
Ron