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

[Jussi Piitulainen]

BartC writes:

> A simpler approach is to treat user-defined operators as aliases for
> functions:
>
> def myadd(a,b):
> 	return a+b
>
> operator ∇:
>    (myadd,2,+3)   # map to myadd, 2 operands, prio 3, LTR
>
> x = y ∇ z
>
> is then equivalent to:
>
> x = myadd(y,z)
>
> However you will usually want to be able overload the same operator
> for different operand types. That means mapping the operator to one of
> several methods. Maybe even allowing the operator to have either one
> or two operands.
>
> Trickier but still doable I think.

Julia does something like that. The parser knows a number of symbols
that it treats as operators, some of them are aliases for ASCII names,
all operators correspond to generic functions, and the programmer can
add methods for their own types (or for pre-existing types) to these
functions.

Prolog opens its precedence table for the programmer. I don't know if
there's been any Unicode activity, or any activity, in recent years, but
there are actually two different issues here: what is parsed as an
identifier, and what identifiers are treated as operator symbols (with
what precedence and associativity).