Immutability and Immutable Data Structures

Immutability is a core principle in computer science where an object or data structure's state cannot be modified after it is created. Consequently, an immutable data structure is one that cannot be altered once instantiated; any operation that appears to modify the structure, such as adding or removing an element, does not change the original but instead returns a new, distinct data structure containing the modification. This approach offers significant advantages, particularly in concurrent and parallel programming, as it eliminates the need for complex locking mechanisms by ensuring data is thread-safe by default. Furthermore, it simplifies program state management and debugging by preventing unintended side effects, making the system's behavior more predictable and easier to reason about.

1. Fundamentals of Immutability
   1. Definition and Core Concepts
      1. Unchangeable State After Creation
      2. Value vs Reference Semantics
      3. Immutability in Data Representation
      4. Temporal Aspects of Immutability
   2. Mutability vs Immutability
      1. Characteristics of Mutable Objects
      2. Characteristics of Immutable Objects
      3. Behavioral Differences in Operations
      4. Side Effects and State Changes
      5. Impact on Program Predictability
   3. Types and Immutability
      1. Primitive Type Immutability
         1. Numeric Types
         2. String Types
         3. Boolean Types
         4. Character Types
      2. Complex Object Immutability
         1. Array Immutability
         2. Record and Struct Immutability
         3. Custom Class Immutability
         4. Collection Immutability
      3. Levels of Immutability
         1. Shallow Immutability
         2. Deep Immutability
         3. Recursive Immutability
         4. Conditional Immutability