Using closure in function scope to make "real" private class members

[zjh]

On Monday, 6 June 2022 at 11:26:35 UTC, Ola Fosheim Grøstad wrote:
>

You need to learn more complicated things about` 'd'`. Add a 
small `'private'`, in fact, you don't need to remember something 
at all.You can get familiar with it after looking at it `several 
times`.
`Small things`, to solve big problems, but you are blocking them 
,it's `so funny`.