Built-in array opSliceAssign

[Adam D. Ruppe]

On Thursday, 25 October 2018 at 12:25:37 UTC, Eduard Staniloiu 
wrote:
> IMHO, this is a bug. The code should lower to calls to opAssing 
> for types that define opAssign.

The spec doesn't exactly say it uses memset, but it does imply it:

https://dlang.org/spec/arrays.html#array-copying

talking about "aggressive parallel code optimizations than 
possible with the serial semantics of C" and "copying" rather 
than "assigned" etc.

but indeed postblit lets this work.