• Andrew Edwards <ridimz_at yahoo.dot.com> Jul 23 2004
• Sha Chancellor <schancel pacific.net> Jul 23 2004

Andrew Edwards <ridimz_at yahoo.dot.com> writes:

Is it possible, or would it even be feasible, to extend mixins such that 
  the scope of a given mixin terminates upon encountering another mixin?

For example:

template someMixin(){ int x; }
template someOtherMixin(){ int y; }

class someClass {

   mixin someMixin;

   void foo() {
     int x; // error: x already defined
     x = 10;
     mixin someOtherMixin; // end of someMixin (within foo())
     y = 10;
     int xy = x * y; // error: x not defined
   }
   mixin someOtherMixin;
   writef(x * y); // outputs 100
}

I can see that there's already allot of problems with this idea. Maybe 
it would be better if we could explicitly terminate the lifespan of a 
particular mixin?

   mixin someMixin;
   x = 10;
   remove someMixin;
   writef(x); // error; x not defined

Any thoughts?

Andrew

Sha Chancellor <schancel pacific.net> writes:

In article <cdsco0$ig$1 digitaldaemon.com>, Andrew Edwards says...
Is it possible, or would it even be feasible, to extend mixins such that 
  the scope of a given mixin terminates upon encountering another mixin?

For example:

template someMixin(){ int x; }
template someOtherMixin(){ int y; }

class someClass {

   mixin someMixin;

   void foo() {
     int x; // error: x already defined
     x = 10;
     mixin someOtherMixin; // end of someMixin (within foo())
     y = 10;
     int xy = x * y; // error: x not defined
   }
   mixin someOtherMixin;
   writef(x * y); // outputs 100
}

I can see that there's already allot of problems with this idea. Maybe 
it would be better if we could explicitly terminate the lifespan of a 
particular mixin?

   mixin someMixin;
   x = 10;
   remove someMixin;
   writef(x); // error; x not defined

Any thoughts?

Andrew


How is this good or usefull?  Or how is it different from doing:

void foo() {
{ mixin someMixin;

} 
{ mixin someOtherMixin;

}
}
What are you trying to accomplish?