Reading notes-The second edition of the basic Python tutorial-the seventh chapter is more abstract

7.1 The magic of the object

Polymorphic objects of different classes use the same action

Packaging

Inherited

7.1.1 Polymorphism

1. Polymorphism and methods

>>>object.getprice ()

>>> ' abc '. COUNT (' a ')

1

>>> [, ' A '].count (' a ')

1

>>> from random import choice

>>> x=choice ([' Hello world! ', [Up, ' e ', ' e ', 4]])

>>> x.count (' e ')

1

>>> x=choice ([' Hello world! ', [Up, ' e ', ' e ', 4]])

>>> x.count (' e ')

2

Python polymorphism does not require type detection, as long as there is the same method, Python polymorphism is actually a bit like the Java function overload

>>> def add (x, y):

... return x + y

...

>>> add

3

>>> Add (' Fish ', ' License ')

' Fishlicense '

>>> def length_message (x):

... print "The length of", repr (x), "is", Len (x)

...

>>> length_message (' Fnord ')

The length of ' Fnord ' is 5

>>> length_message ([+])

The length of [1, 2, 3] is 3

Many of the system functions and operators are polymorphic

The only way to destroy polymorphism is to use function display to do type detection, such as type,isinstance, Issubclass, but try to avoid eliminating

7.1.2 Package

7.1.2 Inheritance

7.2 Classes and types

What exactly is the 7.2.1 class?

7.2.2 to create your own class

Class Person:

def setName (self,name):

Self.name=name

def getName (self):

Return Self.name

def greet (self):

Print "Hello world! I ' m%s "% Self.name

>>> Foo=person ()

>>> Bar=person ()

>>> foo.setname (' Luke Skywalker ')

>>> bar.setname (' Anakin skywaler ')

>>> Foo.greet ()

Hello world! I ' m Luke Skywalker

>>> Bar.greet ()

Hello world! I ' m Anakin skywaler

Self represents a reference to the object itself

>>> Foo.name

' Luke Skywalker '

>>> Bar.name

' Anakin Skywaler '

>>> bar.name= ' Yoda '

>>> Bar.greet ()

Hello world! I ' m Yoda

7.2.3 Properties, functions, and methods

This article from "Small Fish Blog" blog, declined reprint!

Reading notes-The second edition of the basic Python tutorial-the seventh chapter is more abstract