[Aldor-l] [open-axiom-devel] [fricas-devel] Re: About operators for the interpreter.

[Ralf Hemmecke]

On 01/10/2008 10:30 AM, Martin Rubey wrote:
> Ralf Hemmecke <ralf at hemmecke.de> writes:
> 
>> If I am allowed to dream then I would like to be able to write something like
>>
>>    (x: A) \oplus (y: A): A == ...
>>
>> (with \oplus being the actual (unicode) character for that operator).
>>
>> Of course that raises lots of questions and I am not 100% sure whether it
>> would be a good idea to
>>
>>    1) allow unicode in identifiers
> 
> certainly not, unless you also provide means to input them in a ordinary
> terminal.

Each Unicode character has a name.

http://unicode.org/cldr/utility/character.jsp?a=2295
http://unicode.org/cldr/utility/character.jsp?a=2A01

So one could for example still use 7bit ASCII in .spad / .as files and 
there write

(x: A) _'CIRCLED PLUS' (y: A): A == ...

and the Axiom User Interface would do the conversion. Mathematica does 
similar things. Type in

   CirclePlus[A, B] // StandardForm

However, there is still some mechanism missing to specify whether some 
identifier is prefix/infix/postfix and what its precedence is.

I don't care at the moment for such syntactic sugar.

In fact, I also fear that enabling true Unicode (not the syntactic sugar 
I mentioned above) in identifiers might make some programs harder to 
read. I guess, I would have lots of trouble understanding a program 
where the identifiers are denoted by chinese characters.

Does someone know about the JAVA experience? They allow Unicode in 
identifiers. Is the above chinese problem really a problem?

Ralf