In the series of the Python « features » that makes me happy last time i began with two concepts, the with statement and the list comprehensions, now i’m going to talk about Multiple assignments and the import aliases.
- Multiple assignments
It’s a simple idea that lets you return a series of value and on the other end assign those multiple values at the same time, example when you’re splitting a string or extracting groups from a regular expression :
>>> split_me ="here,we, are,again"
# splitting we'll get a list of values
>>> split_me.split(",")
['here', 'we', ' are', 'again']
# if you don't know the number of values you're going to have
# you can't use this features, example :
>>> (start,end) = split_me.split(",")
Traceback (most recent call last):
File "", line 1, in
ValueError: too many values to unpack
# but if you know that there's going to be n values :
>>> (start,end) = split_me.split(" ")
>>> start
'here,we,'
>>> end
'are,again'
- Import aliases
It means what it says, when you import a library or module, you can use aliases, example in Django for shortcuts :
# this is extracted from my own code : from django.http import HttpResponse, HttpResponseRedirect as redirect from django.shortcuts import render_to_response as render</pre>
I won’t start to talk about the standard library as a whole, or libs like Numpy, Scypy, scikit-learn, …. that makes it so easy to just think in Python.
And you ? What are the Python constructs (2.x or 3.x) that makes you feel happy and efficient at the end of the day ?
O. Girardot 