Overriding to!string on enum types

[monarch_dodra via Digitalmars-d-learn]

On Tuesday, 2 September 2014 at 14:59:41 UTC, evilrat wrote:
> sorry, i forgot everything.
> here is example of how to do this
> -----
>
> import std.conv : to;
>
> enum Test
> {
>  One,
>  Two,
>  Three,
> }
>
>
> template to(T: string)
> {
>  T to(A: Test)(A val)
>  {
>   final switch (val)
>   {
>    case Test.One: return "1";
>    case Test.Two: return "2";
>    case Test.Three: return "3";
>   }
>  }
> }
>
>
> void main()
> {
> assert(to!string(Test.One) == "1");
> auto t = cast(Test)2;
> assert(to!string(t) == "3");
> assert(to!int("4") == 4); // shows original to! template works
> }

Word of warning: You are not overriding "to", but rather, simply 
defining your own "to" locally, which resolves as a better match 
in the context where you are using it.

If you pass the enum to another function in another module, your 
"to" will NOT be called.