Templates - What's Up with the template keyword?

[Ron Tarrant]

On Tuesday, 9 April 2019 at 14:25:18 UTC, Mike Parker wrote:

> Off the top of my head, to get a Singleton template, you could 
> implement all of your singleton plumbing (thread safety if you 
> need it, etc) in the template and add a `static _instance` 
> member just as you would for any non-templated singleton:
>
> class Singleton(T) {
>     private static Singleton!T _instance;
>     static Singleton!T instance() {
>         if(_instance is null) {
>             _instance = new Singleton!T;
>         }
>         ...
>     }
>
>     private T _thing;
>     ...
> }
>
> And you can then instantiate directly or, more conveniently, 
> use an alias:
>
> alias Accelerators = Singleton!AccelGroup;
>
> Then:
>
> Accelerators.instance.doSomething();

So, I guess the short answer is 'no.' A template can't really 
substitute for a singleton without actually becoming a singleton 
in and of itself.

I'm still struggling to understand templates, but I'll keep at it.

Thanks, Mike.