Flexible Default Function Parameters via structs with Nullable Fields

[Adam D. Ruppe]

On Tuesday, 30 April 2019 at 08:20:29 UTC, JN wrote:
> It might be nifty by D standards, but for a person not familiar 
> with D

Or, as someone familiar with D, I wonder why not just use a plain 
struct. D allows you to set initial values for struct members 
plainly.

To be frank, I haven't been impressed with any of this author's 
posts.