Dissecting the SS

[Bradley Smith]

J Duncan wrote:
> // what QT-style SS would look like in D
> 
> class AClass
> {
>     void aSignal(int i);
> }
> 
> class BClass
> {
>     void aSlot(int i) { writefln("signal triggered %s", i); }
> }
> 
> void main()
> {
>     AClass a = new AClass;
> 
>     BClass b = new BClass;
> 
>     connect( a, "aSignal(int)", b, "aSlot(int)" );
> 
>     a.aSignal(10);    // -> writes "signal triggered 10"
> }
> 
> 
> i just wanted to give an example of how qt does it. the qt moc generates 
> the code for the function 'aSignal', this gives it a feeling like its 
> part of the language. the moc also generates code to map signal and slot 
> names to addresses. they also provide basic named properties (named data 
> members with set/get methods) this way. this results in a pretty nice 
> system that allows things like automatic signal slot connections in gui 
> classes based on names, (ex. the 'edit1' widget automatically sends a 
> 'textChanged' signal to a slot on a parent widget called 
> 'edit1_textChanged') i dont really have a point to make, i just wanted 
> to give a simple example of qt.
> 

Is there something more to the QT mechanism? I'm not a QT user, but I 
figure there must be more too it. Otherwise, why not use the following?

import std.stdio;

class AClass
{
//  void aSignal(int i);
     void delegate(int) aSignal;
}

class BClass
{
     void aSlot(int i) { writefln("signal triggered %s", i); }
}

void main()
{
     AClass a = new AClass;

     BClass b = new BClass;

     //connect( a, "aSignal(int)", b, "aSlot(int)" );
     a.aSignal = &b.aSlot;


     a.aSignal(10);    // -> writes "signal triggered 10"
}


   Bradley