How to properly Thread.sleep?

[Sad panda via Digitalmars-d-learn]

On Wednesday, 25 March 2015 at 17:23:40 UTC, Israel wrote:
> Ive tried using google but no matter what code i find it either 
> doesnt work, compiler gives me errors or maybe the code is 
> deprecated.
>
> What is the proper way of adding sleep time to a program?
> Ive tried..
>
> import std.stdio;
> import core.thread;
>
> void main()
> {
>      writeln("Sleep..");
>      sleep(200);
>      writeln("done");
> }
>
> but all i get is a compiler error unidentified identifier sleep.
>
> The documentation examples dont make sense. Why would it work 
> this way?
>
> Thread.sleep( dur!("msecs")( 50 ) );  // sleep for 50 
> milliseconds
> Thread.sleep( dur!("seconds")( 5 ) ); // sleep for 5 seconds

Thread.sleep(200.msecs);
Thread.sleep(12.seconds);
Thread.sleep(1.minutes);