Operator Overloading in C++

Operator Overloading

• Allows redefining how operators work for user-defined data types.
• Enables intuitive code by using familiar operators with custom objects.
• Performed through member functions and friend functions.

Rules of Operator Overloading

• Cannot overload operators that work on basic data types (e.g., addition for int, subtraction for double).
• Cannot create new operators.
• Overloading binary operators typically requires a single operand to be an object of the class.
• << and >> operators are overloaded for stream manipulation (e.g., std::cout).

Overloading Through Member Function

• The object used with the operator is implicitly passed as the this pointer.
• Example: Overloading the + operator for addition with member functions.

Overloading Through Friend Function

• Allows access to private members of the class.
• Can handle scenarios where both operands of the operator might not be objects of the class.

Compile-Time Polymorphism

• Achieved through function overloading and template instantiation.
• Resolves the specific function to be called during compilation based on the types of arguments.

Run-Time Polymorphism

• Enables dynamic binding of function calls to objects at runtime.
• Implemented using virtual functions and virtual classes.

Virtual Functions

• Declared using the virtual keyword.
• Provide a mechanism for overriding function behavior in derived classes.

Virtual Classes

• Declared using the virtual keyword.
• Prevent multiple inheritances from creating instances of the base class.

Exception Handling

• Provides a structured way to handle runtime errors or unexpected events.
• Uses try, catch, and throw keywords to capture exceptions and gracefully exit or handle them.

Templates

• Allow writing generic code that can work with different data types without explicit repetitions.
• Function templates enable generic function definitions for various data types.
• Class templates enable creating generic classes that can operate on diverse data types.

Additional Features of C++11, C++14, and C++17

• C++11: Lambdas, auto keyword, nullptr, std::move, range-based for loops, initializer lists, smart pointers, thread support.
• C++14: Generalized constant expressions, return type deduction, auto parameters, binary literals, constexpr for variables and functions.
• C++17: Structured bindings, parallel algorithms (parallel STL), nested namespaces, std:optional, updated std::string_view.

Object Oriented System - Difference Between Procedural and Object Oriented Languages

• Procedural Languages: Focus on procedures (sequences of steps) to solve problems. Data and functions are separate entities. Examples: C, Pascal.
• Object Oriented Languages: Focus on data and the operations that can be performed on that data. Data and functions are combined into objects. Examples: C++, Java, Python.

Object Oriented Paradigm

• Object: A self-contained unit that represents a real-world entity. Holds data and operations.
• Class: A blueprint or template used to create objects. Defines the properties and behavior of objects.
• Encapsulation: Bundling data and methods (functions) within an object, hiding internal details from the outside world.
• Abstraction: Simplifying complex systems by focusing on key aspects and hiding unnecessary details. Similar to a remote control for a TV - you don't need to understand the internal workings to change the channel.
• Inheritance: Creating new classes (child classes) that inherit properties and behaviors from existing classes (parent classes). Allows for code reuse and a hierarchical structure.
• Polymorphism: The ability of different objects to respond to the same message in different ways. This allows for more flexible code and dynamic behavior.

Benefits of OOPs

• Code Reusability: Inheritance allows for reusing existing code in new classes.
• Modularity: Program is divided into smaller, independent objects, making it easier to maintain and modify.
• Data Security: Encapsulation protects data from unauthorized access.
• Extensibility: New features can be easily added without affecting existing code.
• Real-world Modeling: OOPs can model real-world entities and their relationships more naturally.

Applications of OOPs

• Operating Systems: Windows, Linux, macOS
• Game Development: Unreal Engine, Unity
• Web Development: JavaScript frameworks
• Mobile App Development: Android, iOS

Introduction to C++

• Character Set: The set of characters used by the C++ language, including letters, numbers, punctuation marks, and special characters.
• Token: The smallest unit of a C++ program. Can be a keyword, identifier, constant, operator, or punctuation mark.
• Constants: Values that cannot be changed during program execution.
• Variables: Memory locations that store data. They can be changed during program execution.
• Data Types: Classifications of data that determine the type of values a variable can hold. Examples include: int (integer), float (floating-point number), char (character), bool (Boolean).
• Enumeration Types: User-defined data types consisting of named integer constants. Examples: enum days {Mon, Tue, Wed, Thu, Fri, Sat, Sun};
• Operators: Symbols that perform operations on operands (data values). Examples: +, -, *, /, %, =.
• Expressions: Combinations of variables, constants, operators, and function calls that produce a value.
• Operator Precedence and Associativity: Rules that dictate the order in which operators are evaluated in an expression.
• Input: How the program receives data from the user (using std::cin).
• Output: How the program displays information to the user (using std::cout).
• Conditional Statements: Control program flow based on conditions. Examples: if, else, switch.
• Scope of Variables: The region of a program where a variable is accessible and can be used.
• Type Conversion: Converting a value of one data type to another data type.