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# -*- coding: utf-8 -*-

# needed for editors, mandatory when using umlauts

# get help

help(map)

dir(__builtins__)

a = []

dir(a)

help(a)

type([])

# escaping vs. quotes vs. ticks

print " \"WHEE\" "

print ' \'WHOO\' '

print " 'WHOO' "

print ' "WHAA" '

print '''

"WHAA"

"WHOOM"

'''

# raw string -> backslashes are not interpreted -> useful for regex

print r" \"RAW\" "

# Python doesn't know arrays, a list is a sequence with arbitrary types

def func_list():

print "hello world"

a_list = ['a', 'b', 'c', 'd', 2, 3, func_list]

print a_list[0], a_list[1], a_list[2], a_list[3]

# navigate list from end

print a_list[-1], a_list[-2], a_list[-3], a_list[-4]

# a string is a sequence

string = 'efgh'

print string[0], string[1], string[2], string[3]

print string[-1], string[-2], string[-3], string[-4]

# dictionary can hold arbitrary types including functions

# for correct hashing, dictionary keys must be immutable -> String, Tuple, FrozenSet

dic = {

'1': 2,

'a': [1, 2, 3],

1: 'a',

100: 101,

'fun': lambda foo: foo + 1,

(1, 2, 3): "Tuple Key"

}

# print is a statement and doesn't need parentheses

print 100 in dic

"""

this is a

multiline

docstring

"""

# basestring can be unicode string or standard string

isinstance("bla", basestring)

# list comprehension

len([x for x in "bxb" if x == 'x'])

# if, elif, else

if 1 in [1, 2]:

print "hello"

elif 3 in [1, 2]:

pass

else:

pass

# for loops

for i in range(10):

print i

else:

# called when no break exits the loop

print "the end1"

# tuple assignment

a, b = 1, 2

a, b = b, a

a, b = 1 + 1, "axb".count('x')

# ternary operator equivalent

def bla(n):

return n if n in [0, 1] else 100

# 'is' compares references

# '==' is deep equals but must be implemented by comparator

a = []

b = a

c = []

a == c # True

a == b # True

a is b # True

a is c # False

a = 3

b = 3

True == a is b

# try:

# import foo

# except

# foo = MyFoo()

# magic methods and operator overloading

# __init__

# __len__ -> with naming conventions operator overloading is possible

# tuple with one element

a = (1,)

# replace elements in a list

a = range(10)

a[1::4] = [None] * 3

# remove elements via pop()

a.pop()

a.pop(0)

a.pop(3)

# function definitions

def funky(aa, bb="optional", *args, **keywords):

print aa, bb

print args

print keywords

def drunky(p1, p2, p3):

print "in g", p1, p2, p3

drunky(*[1, 2, 3])

drunky(**{"p1": 4, "p2": 5, "p3": 5})

funky(1)

funky(1, 2)

funky(1, 2, 3, 4, 5)

funky(1, 2, 3, 4, 5, ai=6, xy=[1, None])

lamm = lambda la: la + 1

print lamm(24)

arr = [1, 2, 3]

map(lambda ch: str(ch), arr)

map(str, arr)

"""

Questions

* is method overloading possible?

* automatic type conversions

"""

# support starting from command line

if __name__ == "__main__":

s = raw_input("give me 1: ")

# assert with message

assert s == "1", 's is not 1'

# react on Ctrl+C

try:

raw_input("Give me some input")

except KeyboardInterrupt:

import sys # can be done everywhere

sys.exit(1)