Challenge: Motivating examples for ...

[Paul Backus]

On Saturday, 25 April 2020 at 15:17:35 UTC, Steven Schveighoffer 
wrote:
> I propose a function any which takes a range and returns true 
> if any element matches the provided one. And another one 
> all(val) which does the same if all are the value. This gives 
> us maximum flexibility.

Looks like std.algorithm.any and std.algorithm.all can already do 
this.