From: Charles D Hixson <charleshixsn@...>
Date: 2006-11-23T02:37:12+09:00
Subject: Re: Ruby vs Java vs c++

M. Edward (Ed) Borasky wrote:
> Charles D Hixson wrote:
>> Operator redefinition can be seriously abused.  It's also something 
>> that's very powerful when done correctly.  I can see an argument for 
>> requiring that the *standard* operators not be redefined.  This 
>> doesn't mean that there shouldn't be user defined operators that CAN 
>> be treated just as any other (virtual) function.  Perhaps a 
>> requirement like "A user operator must begin with a '|' character and 
>> contain no whitespace in it's name.  It may contain any other 
>> non-control character, and must be delimited by whitespace." would 
>> suffice.
> Bah! Double Bah! Triple Bah!
>
> 1. Every programmer is entitled to define his or her very own personal 
> programming language using whatever syntax and semantics makes the job 
> easy. As long as it's simply a dialogue between one programmer and one 
> machine, who else cares?
>
> 2. *However*, the minute a second programmer, a manager, a user, or 
> another machine enters the picture, that programmer needs to 
> communicate with more entities, thus requiring a standardized language 
> *and* a meta-language for communicating about the language.
>
> 3. Programming languages evolved from symbolic logic, algebra and 
> English, at least here in the USA and in the United Kingdom, where the 
> initial development was begun during WW II and the early years of the 
> Cold War. (No, I haven't forgotten about Konrad Zuse or the early 
> Russian computers -- they just didn't have much influence on 
> programming languages).
>
> C++ has *way* too many features, both syntactic and semantic, to be of 
> much use to me. Sure, any programmer can work in a readable subset of 
> C++, but most don't. Most have their own team dialect of C++. As far 
> as I'm concerned, there's only one usable dialect of C++ -- ANSI C. :)
>
You are thinking about C++.  I am thinking about Eiffel and Ada and 
Python.   C++ got LOTS of things wrong, and only became popular because 
it was an effortless transition from C.  You are taking a warning from 
C++.  I am taking a warning from Algol98.  There's lots of ways to 
design something improperly.  Just because one of them is selected 
doesn't mean the basic idea is wrong.  (C++ also gave multiple 
inheritance a bad name.  Eiffel proved that the bad name wasn't justified.)

Mind you, every language has it's warts.  More important than allowing 
liberal operator redefinition I believe would be the optional inclusion 
of function name on the matching end statement.  This would allow many 
errors to be localized.  Think of it as a "compiler hint".

NOTE:  an operator *IS* a function.  If you are against user defined 
operators, then for consistency you should be against user defined 
functions.  I really doubt that you are going to pick that choice.

P.S.:  I think that the way Python defines operators works well for the 
"built in" operators, but I'm not sure that it's appropriate for 
generalized user defined operators.  The form I used in Eiffel was to 
precede and follow the operator name with a pipe character, thus:  |*| 
for matrix multiplication.  Eiffel allows(allowed?) this form, but 
doesn't encourage it.