A java hobbyist programmer learning python

[elhombre]

"Paul Rubin" <http://phr.cx@NOSPAM.invalid> wrote in message 
news:7xy6x9nzwd.fsf at ruckus.brouhaha.com...
> Chris Rebert <clp2 at rebertia.com> writes:
>> > class Calculator(): ...
>
>> Delete the 3 Java-ish accessor methods; good Python style just uses
>> the attributes directly (i.e. self.operator instead of
>> self.getOperator()).
>
> I think I would get rid of the whole Calculator class unless there was
> a good reason to keep it (i.e. you are going to have several
> Calculators active in the program simultaneously).  Just write
> straightforward imperative code without bothering with the OO stuff
> that is mandatory in Java.
>
>> Rather than have a long if-elif-else chain like this, you can use a
>> dictionary with functions as values. For example:
>>
>> def add(x, y):
>>     return x + y
>
> These functions are already defined in the operator module, and you
> can also define them inline with the lambda operator.
>
> Here is my version of the program:
>
>    import sys
>    from operator import add, mul, sub, div
>
>    op, x, y = sys.argv[1:4]
>
>    opdict = {'+': add, '*': mul, '-': sub, '/': div}
>
>    try:
>      func = opdict[op]
>    except KeyError:
>      print 'wrong argument supplied'
>      sys.exit()
>
>    print func(int(x), int(y))
>
> Note that like the original, it doesn't check for valid numeric args.


Good point about the class. I really only did that to begin to learn the 
class syntax. I had not added any exception handling as I was taking it a 
step at a time. Most of the first few hours were spent mucking around with 
TextMate, Netbeans and Wing IDE. I finally got Netbeans working to the point 
where something would run.

Thanks very much Paul.