Zen of python

Julien Bouquillon

revolunet

revolunet

Productivity

Portability

Community

Basics

Indentationif y > 42: print "y is bigger than 42" else: print "y is smaller (or equal) than 42"

Typage dynamiquex = 5 y = 'hello, world' z = Company(name = 'revolunet')

Assignementsx = y = 5 z = 1 < x < 10 # Truea, b = 42, 34

#1

Slices

une_liste = [1, 2, 3, 'coucou', 4, 5, 6]

une_liste[start:end[:step]]

une_liste[3] # 'coucou' une_liste[-2] # 5

une_liste[1:3] # 2, 3 une_liste[::3] # [1, 'coucou', 6] une_liste[::-1] # [6, 5, 4, 'coucou', 3, 2, 1]

une_liste[::3] = [0, 0, 0] une_liste # [0, 2, 3, 0, 4, 5, 0]

#2

Strings

chaine = "bonjour la cantine"

chaine[:7] # 'bonjour' chaine.split()[0] # 'bonjour' chaine[::-1] # 'enitnac al ruojnob'

print "python rox " * 5 # python rox python rox python rox python rox python rox

print "you are %.2f years young" % (3*10) # 'you are 30.00 years old'

data = {'firstname':'Guido', 'company':'Google'} print "hello %(firstname)s from %(company)s" % data # 'hello Guido from Google'

#3

Lists comprehension#4

S = [x for x in range(10) if x**2 > 3] # [2, 3, 4, 5, 6, 7, 8, 9]

liste1 = [1, 2, 3] liste2 = [3, 4, 5] print [x * y for x in liste1 for y in liste2] # [3, 4, 5, 6, 8, 10, 9, 12, 15]

Decorators

modifier le comportement de fonctions existantes

#5def calcul(x, y): return x*y

@memoize def calcul(x, y): return x*y

@login_required @log(logger = '/var/log/secret_access.log') def view_secret_stuff(request): secret_stuff = ... return secret_stuff

Python requests

import requests import simplejson

req = requests.get('https://api.github.com/users/revolunet/repos',                auth=('revolunet','ucrazy ?'))

# convert the Json to a python dictionary

data = simplejson.loads(req.content)

for repo in data: print repo['name'], ':', repo['description']

#6

POO

class Animal(object): ...

class Human(Animal): ...

class Robot(object): ...

class Cyborg(Human, Robot): ...

#7

Le comportement de chaque object peut être modifié à volonté

- creation, suppression d'objects - comparaisons, opérations... - créer des classes itérables, callables...

Django ORM query

filters = { 'author__name__startswith': 'Guido', 'date_published__gte':datetime(2011, 1, 1), 'price__lte':30 }

results = Books.objects.filter(**filters)

results = results.exclude(publisher__name = 'Eyrolles')

results = results.order_by('price')[:50]

print results

#8

revolunetrevolunet

Merci:)