Handling arbitrary char ranges

[Matt Kline via Digitalmars-d-learn]

On Wednesday, 20 April 2016 at 19:29:22 UTC, ag0aep6g wrote:
> Maybe use ubyte[] for the buffer type instead.

I don't have an option here, do I? I assume HTTP.onSend doesn't 
take a `delegate size_t(ubyte[])` insetad of a `delegate 
size_t(void[])`, and that the former isn't implicitly convertible 
to the latter.

> I think your problems come more from wanting to accept string, 
> which simply isn't a char range

Is this due solely to the "auto-decode" behavior? Generally, 
(except apparently in this case) don't arrays of type T qualify 
as InputRanges of type T?