Book Image

Metaprogramming with Python

By : Sulekha AloorRavi
Book Image

Metaprogramming with Python

By: Sulekha AloorRavi

Overview of this book

Effective and reusable code makes your application development process seamless and easily maintainable. With Python, you will have access to advanced metaprogramming features that you can use to build high-performing applications. The book starts by introducing you to the need and applications of metaprogramming, before navigating the fundamentals of object-oriented programming. Next, you will learn about simple decorators, work with metaclasses, and later focus on introspection and reflection. You’ll also delve into generics and typing before defining templates for algorithms. As you progress, you will understand your code using abstract syntax trees and explore method resolution order. This Python book also shows you how to create your own dynamic objects before structuring the objects through design patterns. Finally, you will learn simple code-generation techniques along with discovering best practices and eventually building your own applications. By the end of this learning journey, you’ll have acquired the skills and confidence you need to design and build reusable high-performing applications that can solve real-world problems.
Table of Contents (21 chapters)
1
Part 1: Fundamentals – Introduction to Object-Oriented Python and Metaprogramming
4
Part 2: Deep Dive – Building Blocks of Metaprogramming I
11
Part 3: Deep Dive – Building Blocks of Metaprogramming II

Generating a class with attributes

In this section, we will generate code for a class, along with a list of attributes, that will also be included dynamically in the class. Generating code for a class alone can give the initial skeletal structure for a module, whereas we need to add attributes if we want to make the class more specific. The following flow diagram represents the sequence of steps to be followed for this example:

Figure 14.5 – A code generation sequence for a class with multiple attributes

Let us look at the code for this example:

  1. We will first define a variable to provide classname as input, followed by a classtemplate to create the template of the class declaration:
    classname = "VegCounter"
    classtemplate =  '''class ''' +classname+ ''':'''+'\n    '
  2. In the next step, let us define another variable to provide attribute...