m03-mutability

What problem does it solve?

This skill teaches how to enforce const correctness and manage mutable state in C++ to prevent data races and preserve logical immutability, including locking strategies and proper use of mutable members.

Core Features & Use Cases

• API Contracts: const methods guarantee no visible state modification.
• Mutable State Management: design patterns for mutable caches guarded by synchronization primitives.
• Thread-Safety Guidance: guidelines for when to use std::mutex or std::shared_mutex in API surfaces.
• Use Case: implement a thread-safe cache inside a const method to balance performance and safety.

Quick Start

Construct a minimal class that demonstrates a const method safely accessing a mutable cache protected by a mutex.