type of array element, type of assoz key?

[Frits van Bommel]

dennis luehring wrote:
> how can i get the element type of an array at compiletime?
> 
> example:
>   int test[5] --> int
>   double test[] --> double
> 
> and what is the type of the key of an assoz. array?
> 
>   int test[char[]] --> int, char[]
>   double test[int] --> double, int

(This sort of post is more appropriate in digitalmars.D.learn, followups 
set)

typeof to the rescue:
-----
import std.stdio;

void main() {
     // (typeid is just wrapped around the types to make them printable)

     // Element type of regular arrays: typeof(arr[0]);
     {
         int test[5];
         writefln(typeid(  typeof(test[0])  ));
     }
     writefln();
     {
         double test[];
         writefln(typeid(  typeof(test[0])  ));
     }
     writefln();

     // Assoc. arrays:
     // key type == typeof(arr.keys[0])
     // value type == typeof(arr.values[0])
     {
         int test[char[]];
         writefln(typeid(  typeof(test.values[0])  ));
         writefln(typeid(  typeof(test.keys[0])    ));
     }
     writefln();
     {
         double test[int];
         writefln(typeid(  typeof(test.values[0])  ));
         writefln(typeid(  typeof(test.keys[0])    ));
     }
}
-----
output:
=====
int

double

int
char[]

double
int
=====