Template class with dispatched properties

[Chris Cain]

On Friday, 8 November 2013 at 02:13:01 UTC, Ross Hays wrote:
> My end goal is to be able to instantiate a vector with a syntax
> like...
> `Vector!(2, float) vec = new Vector!(2, float)();`
>
> ...
>
> Any suggestions?

Greetings,

This works:

---
import std.stdio;

struct Vector(int N, T) if (N <= 3) {
   private T[N] data;

   public @property
   void opDispatch(string fieldName, Args ...)(Args args) if 
(Args.length == 1 && fieldName.length == 1 && 
cast(size_t)(fieldName[0] - 'x') < N) {
     static immutable offset = cast(size_t)(fieldName[0] - 'x');
     data[offset] = args[0];
   }

   public @property
   T opDispatch(string fieldName, Args ...)(Args args) if 
(Args.length == 0 && fieldName.length == 1 && 
cast(size_t)(fieldName[0] - 'x') < N) {
     static immutable offset = cast(size_t)(fieldName[0] - 'x');
     return data[offset];
   }
}

void main() {
   auto vec = Vector!(2, float)();
   vec.x = 1.0;
   vec.y = 2.0;
   //vec.z = 3.0; // Doesn't compile, as expected for a Vector!(2, 
float);

   writeln("vec.x = ", vec.x, " and vec.y = ", vec.y);
}

---

Minor tweaks might be necessary, but that should get you started.