Well, I finally ran into a Python Unicode problem, sort of

[Jussi Piitulainen]

Lawrence D’Oliveiro writes:

> On Monday, July 4, 2016 at 6:08:51 PM UTC+12, Jussi Piitulainen wrote:
>> Something could be done, but if the intention is to allow
>> mathematical notation, it needs to be done with care.
>
> Mathematics uses single-character variable names so that
> multiplication can be implicit.

Certainly on topic, though independent of Unicode. I was thinking of
different classes of operator symbols.

> An old, stillborn language design from the 1960s called CPL* had two
> syntaxes for variable names:
> * a single lowercase letter, optionally followed by any number of primes “'”;
> * an uppercase letter followed by letters or digits.
>
> It also allowed implicit multiplication; single-letter identifiers
> could be run together without spaces, but multi-character ones needed
> to be delimited by spaces or non-identifier characters. E.g.
>
>   Sqrt(bb - 4ac)
>   Area ≡ Length Width
>
> *It was never fully implemented, but a cut-down derivative named BCPL
> did get some use. Some researchers at Bell Labs took it as their
> starting point, first creating a language called “B”, then another one
> called “C” ... well, the rest is history. 

There's been at least D, F, J, K (APL family), R, S (_before_ R), T (a
Lisp), X (the window system), Z (some specification language).

Any single-letter non-ASCII names yet? Spelled-out like Lambda and Omega
don't count.