[Issue 13936] groupBy must be redone

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=13936

--- Comment #44 from hsteoh at quickfur.ath.cx ---
I didn't look further into it, but the current groupBy code was inferred
nothrow, but the new code was inferred as throwing, so the nothrow unittests
refused to compile. The compiler error indicated that it was the RefCounted
ctor/dtor that broke nothrow.

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