Pylint and Glossary of Object-Oriented Programing Terms

Pylint

Pylint is a tool that checks for errors in Python code, tries to enforce a coding standard and looks for code smells. It can also look for certain type errors, it can recommend suggestions about how particular blocks can be refactored and can offer you details about the code's complexity.

Pylint will display a number of messages as it analyzes the code and it can also be used for displaying some statistics about the number of warnings and errors found in different files. The messages are classified under various categories such as errors and warnings.

The code is given an overall mark, based on the number and severity of the warnings and errors.

Pylint Installation

One of the easist ways to download Pylint is by using "pip". Pip is a package management system used to install and manage software packages written in Python. It is included with recent versions of Python. If you already have a 64-bit version of Python installed, the "Installing Python" section can be skipped.

To install it on systems such as Windows 10, Mac OS, Linux, use the following command:

To verify the pylint installation, type the following command

Glossary of Object-Oriented Programing Terms

1. Class

A class is a user-defined blueprint or prototype from which objects are created. Classes provide a means of bundling data and functionality together. Creating a new class creates a new type of object, allowing new instances of that type to be made. Each class instance can have attributes attached to it for maintaining its state. Class instances can also have methods (defined by their class) for modifying their state.

2. Class Objects

An Object is an instance of a Class. A class is like a blueprint while an instance is a copy of the class with actual values.

An object consists of :

1. State: It is represented by the attributes of an object. It also reflects the properties of an object.
2. Behavior: It is represented by the methods of an object. It also reflects the response of an object to other objects.
3. Identity: It gives a unique name to an object and enables one object to interact with other objects.

3. Constructor

Constructors are generally used for instantiating an object. The task of constructors is to initialize(assign values) to the data members of the class when an object of the class is created. In Python the __init__() method is called the constructor and is always called when an object is created.

4. Inheritance

Inheritance is the capability of one class to derive or inherit the properties from another class. The benefits of inheritance are:

1. It represents real-world relationships well.
2. It provides reusability of a code. We don’t have to write the same code again and again. Also, it allows us to add more features to a class without modifying it.
3. It is transitive in nature, which means that if class B inherits from another class A, then all the subclasses of B would automatically inherit from class A.

5. Encapsulation

Encapsulation is one of the fundamental concepts in object-oriented programming (OOP). It describes the idea of wrapping data and the methods that work on data within one unit. This puts restrictions on accessing variables and methods directly and can prevent the accidental modification of data. To prevent accidental change, an object’s variable can only be changed by an object’s method. Those types of variables are known as private variable.

6. Polymorphism

In Python, Polymorphism lets us define methods in the child class that have the same name as the methods in the parent class. In inheritance, the child class inherits the methods from the parent class. However, it is possible to modify a method in a child class that it has inherited from the parent class. This is particularly useful in cases where the method inherited from the parent class doesn’t quite fit the child class. In such cases, we re-implement the method in the child class. This process of re-implementing a method in the child class is known as Method Overriding.

7. Abstraction

Abstraction is used to hide the internal functionality of the function from the users. The users only interact with the basic implementation of the function, but inner working is hidden. User is familiar with that "what function does" but they don't know "how it does."

8. Factory Method

Factory Method is a creational design pattern used to create concrete implementations of a common interface. It separates the process of creating an object from the code that depends on the interface of the object.

9. Fixture Method

Fixtures are functions, which will run before each test function to which it is applied. Fixtures are used to feed some data to the tests such as database connections, URLs to test and some sort of input data. Therefore, instead of running the same code for every test, we can attach fixture function to the tests and it will run and return the data to the test before executing each test.

10. Facade

A facade is a type of pattern which masks more complex software functions.While Facade decreases the overall complexity of the application, it also helps to move unwanted dependencies to one place.

11. Design Patterns

Design Patterns is the most essential part of Software Engineering, as they provide the general repeatable solution to a commonly occurring problem in software design.

12. Instantiation

Used to create an object instance from a class (instantiate).

13. Namespace

A namespace is a collection of currently defined symbolic names along with information about the object that each name references. You can think of a namespace as a dictionary in which the keys are the object names and the values are the objects themselves. Each key-value pair maps a name to its corresponding object.

14. Type Hint

For some time now, Python has had the ability to “annotate” names with type information, in one form or another. With Python 3.5, type hints officially became part of the language (PEP 484). Using a linter or code-checking tool, developers can check the consistency of variables and their types across a code base, and perform static analyses of code that would previously have been difficult or impossible. All this is done ahead of time, before the code runs.

15. Type Cast

In Python, Type Casting is a process in which we convert a literal of one type to another.

16. Attribute

Attributes of a class are function objects that define corresponding methods of its instances.

17. Behavior

The behavior of an object is defined by its methods, which are the functions and subroutines defined within the object class.