Python object references
Think of Python working in terms of named references to objects rather than variables and values.
Assignment doesn't put a value in a box. It attaches a name tag to an object.
Assigning from one reference to another puts two name tags on the same object.
The Python garbage collector will reclaim unreachable objects - those objects with no name tag.
Object identity and equivalence
The
id()function returns a unique and constant identifier but should rarely, if ever, be used in production.The is operator determines equality of identity. That is, whether two names refer to the same object.
We can test for equivalence using the double-equals operator.
Function arguments and return values
Function arguments are passed by object-reference, so functions can modify their arguments if they are mutable objects.
If a formal function argument is rebound through assignment, the reference to the passed-in object is lost. To change a mutable argument you should replace its contents...
The Python Apprentice
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The Python Apprentice
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Overview of this book
Experienced programmers want to know how to enhance their craft and we want to
help them start as apprentices with Python. We know that before mastering Python you need to learn the culture and the tools to become a productive member of any Python project. Our goal with this book is to give you a practical and thorough introduction to Python programming, providing you with the insight and technical craftsmanship you need to be a productive member of any Python project. Python is a big language, and it’s not our intention with this book to cover everything there is to know. We just want to make sure that you, as the developer, know the tools, basic idioms and of course the ins and outs of the language, the standard library and other modules to be able to jump into most projects.
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Current Title:
The Python Apprentice
Table of Contents (21 chapters)
Title Page
Credits
About the Authors
www.PacktPub.com
Customer Feedback
Preface
Free Chapter
Getting started
Strings and Collections
Modularity
Built-in types and the object model
Exploring Built-in Collection types
Exceptions
Comprehensions, iterables, and generators
Defining new types with classes
Files and Resource Management
Unit testing with the Python standard library
Debugging with PDB
Afterword – Just the Beginning
Virtual Environments
Packaging and Distribution
Installing Third-Party Packages
Customer Reviews