[Tutor] Learning python as a thing to do

[Alan Gauld]

> I am a Rubyist, but I've decided to learn Python 

Welcome, could be interesting. I'm a pythonista and 
have learned Ruby but not used it for anything significant 
yet.

> At any rate, so far Python seems to be a very good
> language. Not a great language, but still very good.

There is only one great language: Lisp :-)

> So far, some things I dont care for...
> immutable strings
> no case statement

Yes, most folks find those concepts pretty strange.
Personally I don't miss case statements (see a recent thread) 
I usually find Pythons stricture means I rethink the design 
and usually manage to avoid the need (and potential bugs that 
are inherent in case structures...) but mutable strings would 
be nice, although potentially dangerous for dictionary keys.

> lack of internal iterators

NOt sure what you mean by this one, can you expand?

> The mixing of functions and methods

You mean the fact that Python doesn't insist on everything 
being an object? That simply reflects that Python can be 
used in several difreent paradigms. Functional Programming 
is the biggest "modern" alternative to OOP and support for 
functions as first class objects supports that style. Ruby 
can fake it with its top level "invisible" object, but Python 
just makes that style a natural part of the language.

OTOH if you mean the inconsistencies in the use of methods 
versus functions in the base language (eg files have a close 
method but an open function) then I agree and Python is slowly 
removing those with each release. The biggest step being 
the introduction of strings as objects/methods and another 
step forward being the new-style classes in v2.x

This is one area where Matz learned lessons from Perl/Python 
when he invented Ruby - the advantage of going second (or 
third or fourth...)

> Question(s):
> Are there any good books/documents that actually
> examine the ruby way vs python way? (by someone that
> knows both languages)

NOt that I know of.

> The other day I saw a post from a gentleman trying to
> do a basic prompt and add type of calculator.
> He wanted to assign the +, or * operator to a variable
> to use, but I believe he was told you have to use the
> literal +, or *.

Thats possible using the operator module.

> Are these operators constanst in Python?

Not really, in that you can override them 
(__add__, __Sub__, __mul__ etc) and the operator module 
gives access to the common ones in a generic kind of way.

> If so, is there not a way to send that constant to
> act apon another variable or variables that refer to
> numbers?

I didn't see the post but it sounds as if the poster should 
have been able to do what [s]he wanted.

> In ruby, you can rerence the * operator
> operator = :*   
> num1 = 4
> num2 = 6
> num1.send(operator,num2)

In Python:

import operator
num1 = 4
num2 = 6
operator.mul(num1,num2)

Alan G.


> which returns 24
> 
> Have a nice day :-)
> 
> 
> 
> 
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