partially mutable immutable type problem, crazy idea

[Yuxuan Shui]

On Wednesday, 9 May 2018 at 00:58:51 UTC, jmh530 wrote:
> On Tuesday, 8 May 2018 at 22:31:10 UTC, Yuxuan Shui wrote:
>> snip]
>
> This doesn't compile for me on run.dlang.io:
>
> onlineapp.d(22): Error: template onlineapp.f cannot deduce 
> function from argument types !()(B), candidates are:
> onlineapp.d(1):        onlineapp.f(T)(immutable T a)

Not supposed to. Was proposing an (crazy) idea here.