A tuple in order to pass returned values ?

[Steven D'Aprano]

Jean-Michel Pichavant wrote:

> In a general manner, ppl will tend to use the minimum arguments
> required. However, do not pack values into tuple if they are not related.

How would you return multiple values if not in a tuple?

Tuples are *the* mechanism for returning multiple values in Python. If
you're doing something else, you're wasting your time.


> A better thing to do would be to use objects instead of tuples, tuples
> can serve as lazy structures for small application/script, they can
> become harmful in more complexe applications, especialy when used in
> public interfaces.

First off, tuples *are* objects, like everything else in Python.

If you are creating custom classes *just* to hold state, instead of using a
tuple, you are wasting time. Instead of this:

class Record:
    def __init__(self, x, y, z):
        self.x = x
        self.y = y
        self.z = z

result = Record(1, 2, 3)

Just use a tuple or a namedtuple: the work is already done for you, you have
a well-written, fast, rich data structure ready to use. For two or three
items, or for short-lived results that only get used once, an ordinary
tuple is fine, but otherwise a namedtuple is much better:

from collections import namedtuple
result = namedtuple('Record', 'x y z')(1, 2, 3)



-- 
Steven