Fully dynamic d by opDotExp overloading

[Andrei Alexandrescu]

Steven Schveighoffer wrote:
> I gave this a lot of thought, and I think here is a possible solution:
> 
> the main reason I'm hesitant on this idea is because of code like this:
> 
> class X
> {
>   auto opDotExp(string fname, T...)(T args)
>   {
>      if(fname == "blah")
>        return foo(args);
>      else if(fname == "blither")
>        return bar(args);
>      // else, nothing happens
>   }
> }
> 
> Which leaves code open to lots of compiled code that doesn't do the 
> right thing (or throws some runtime exception).  What would be nice is 
> if the default behavior is what statically bound functions do, that is, 
> compile error, and only let the cases be handled which the author 
> expects to handle.

class X
{
   auto opDotExp(string fname, T...)(T args)
   {
      static if(fname == "blah")
        return foo(args);
      else static if(fname == "blither")
        return bar(args);
      else static assert(0, "Dunno how to "~fname);
   }
}


Andrei