Sign In Start Free Trial
Account

Add to playlist

Create a Playlist

Modal Close icon
You need to login to use this feature.
  • Book Overview & Buying Mastering Object-oriented Python
  • Table Of Contents Toc
  • Feedback & Rating feedback
Mastering Object-oriented Python

Mastering Object-oriented Python

By : Steven F. Lott
4.2 (13)
close
close
Mastering Object-oriented Python

Mastering Object-oriented Python

4.2 (13)
By: Steven F. Lott

Overview of this book

Table of Contents (26 chapters)
close
close
Mastering Object-oriented Python
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Some Preliminaries
Index

Designing with ABC callables


There are two easy ways to create callable objects in Python, as follows:

  • Using the def statement to create a function

  • By creating an instance of a class that uses collections.abc.Callable as its base class

We can also assign a lambda form to a variable. A lambda is a small, anonymous function that consists of exactly one expression. We'd rather not emphasize saving lambdas in a variable as it leads to the confusing situation where we have a function-like callable that's not defined with a def statement. The following is a simple callable object that has been created from a class:

import collections.abc
class Power1( collections.abc.Callable ):
    def __call__( self, x, n ):
        p= 1
        for i in range(n):
            p *= x
        return p
pow1= Power1()

There are three parts to the preceding callable object, as follows:

  • We defined the class as a subclass of abc.Callable

  • We defined the __call__() method

  • We created an instance of the class, pow1()

Yes, the...

Unlock full access

Continue reading for free

A Packt free trial gives you instant online access to our library of over 7000 practical eBooks and videos, constantly updated with the latest in tech

Create a Note

Modal Close icon
You need to login to use this feature.
notes
bookmark search playlist download font-size

Change the font size

margin-width

Change margin width

day-mode

Change background colour

Close icon Search
Country selected

Close icon Your notes and bookmarks

Delete Bookmark

Modal Close icon
Are you sure you want to delete it?
Cancel
Yes, Delete

Delete Note

Modal Close icon
Are you sure you want to delete it?
Cancel
Yes, Delete

Edit Note

Modal Close icon
Write a note (max 255 characters)
Cancel
Update Note

Confirmation

Modal Close icon
claim successful

Buy this book with your credits?

Modal Close icon
Are you sure you want to buy this book with one of your credits?
Close
YES, BUY