OOP no Python

[Chris Angelico]

2014-06-27 0:16 GMT+10:00 Samuel David <samuel.costa at eos-hoepers.com>:
> Mas estou com uma dúvida referente ao tópico “Por que eu deveria usar Python
> e não <insira aqui a sua linguagem favorita>?”.

Google Translate tells me you're asking "Why use Python instead of
<some other language>?". (I'm going to respond only in English, as my
Portuguese is basically nil. Sorry.) Well, there are a lot of reasons
:)

One is that Python is a clear and simple language; a form of
"executable pseudo-code". If you start by writing what you want to do
as comments, then translate slightly into a more formal grammar to
make pseudo-code, you're pretty close to having stubby Python code.
There's a minimum of fuss, the language does its best to get out of
the way and let you do your work.

Closely related to that is Python's excellent interactive mode. Since
you don't have to declare variables or anything, you can simply fire
up Python interactively (eg by just typing "python", or with something
like IDLE), and it is simultaneously a clean environment in which you
just say "a = 2+3" and assign 5 to a, and a full programming
environment that gives you all the power you need (for instance, you
can define functions, then call them - that's something I was never
able to do in REXX, at least not without some fiddling). In contrast,
a language like Pike is that bit more wordy at its interactive prompt,
as you need to make appropriate declarations. And any language that
doesn't have first-class functions is going to be much less clean for
this sort of work - REXX doesn't have any concept of run-time function
creation at all, except that it can (ab)use the file system for that
job.

Another advantage of Python is Unicode support. Particularly if you're
using Python 3.3 or newer, you're guaranteed that a string consists of
a sequence of Unicode codepoints, and you can depend on being able to
index and slice it accordingly. This is way WAY better than C, or PHP,
or any other language that sticks its head in the sand and tries to
ignore character encodings altogether; and it's better than UTF-16
languages like JavaScript, because you avoid the subtle errors that
can creep in when you index a string with astral characters. You can
happily write your program and test it on Portuguese text, and be
confident that it'll work just as well with Hebrew.

Finally, Python is a well-established language. You can write an
application in Python and simply tell people "You'll need a Python
interpreter, version 3.3 or better, to run this", and be confident
that they'll be able to get one - most Linux distros include Python in
their repositories, a Mac probably has it installed, on Windows it's
just a matter of fetching the .msi, and there are unofficial builds
for obscure platforms like OS/2. (Which I make good use of,
incidentally. We have a legacy OS/2 system, now running as a virtual
machine under Linux, on which we run certain legacy software. How do
we back up the crucial data from there? Simple: A Python script that
archives the necessaries, sends them via TCP/IP, and reports its
status to the user. I think it took me all of half a screenful of code
to write that.)

There are other languages that I use and love, too; each one has its
strengths and weaknesses. These are just a few of Python's strengths.

ChrisA