On Sunday, 14 February 2021 at 08:46:34 UTC, frame wrote:
The first instance is in A - and why opAssign then works there?
Sorry I didn't pay too much attention.
It seems the detection of first assignment only happens when the
field and constructor have the same parent, so it doesn't work
either if the field is from a base or derived class (your case by
means of casting 'this').
I don't think this is intended rather it appears to be a
bug/deficiency in the constructor flow analysis of DMD, which
from what I'm reading is very rudimentary.
