register mixin

[Frank Benoit]

/**/   // I want to use mixin very compact, like this:
/**/
/**/   class Speed : Signal!(int){
/**/     mixin Scaling( 0, 1.23, "km/h") scale_kmh;
/**/     mixin NamedRange( 100, 200, "HIGH SPEED" ) highSpeed;
/**/     mixin NamedValue( 250, "MAX" ) maxSpeed;
/**/   }
/**/
/**/   Speed speed = new Speed;
/**/   // set the internal 'Signal!(int).mValue'
/**/   // variable to a scaled value
/**/   speed.scaled_kmh.setValue( 250 );
/**/   // set the internal 'Signal!(int).mValue' variable to 250
/**/   speed.maxSpeed.set();
/**/
/**/   // So far no problem i think.
/**/
/**/   // And now I want the way back:
/**/   // Each mixin should register a class or delegate or ...
/**/   // to give the Signal class the possibility to find the
/**/   // Label "MAX" or print the scaled "km/h"
/**/
/**/   class Signal(T){
/**/     // ....
/**/     public char[] toString(){
/**/       char[] result;
/**/       foreach( SomeThing st; list ){
/**/         result ~= st.toString( mValue );
/**/       }
/**/       return result;
/**/     }
/**/     // ....
/**/   }
/**/

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/*     Is there any way?       */
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