AA char[] as key

[bearophile]

Andrew Wiley:

> If the compiler is basically going to disallow using the AA as
> anything but a long[string], it should really disallow declaring
> anything with a mutable key type. Disallowing mutable keys at that
> assignment site but allowing them in the type is confusing.

Two related bug reports:
http://d.puremagic.com/issues/show_bug.cgi?id=4475
http://d.puremagic.com/issues/show_bug.cgi?id=6253

Bye,
bearophile