C++ standards

Navigating the Evolution of C++: A Guide to Standards and Features

The C++ programming language has long been revered for its power, flexibility, and efficiency. But to ensure consistency and compatibility, it must adhere to well-defined standards. This post delves into the C++ standards landscape, exploring each major iteration and its key features.

Table of Contents

• Introduction to C++ Standards
• C++98 (ISO/IEC 14882:1998)
• C++03 (ISO/IEC 14882:2003)
• C++11 (ISO/IEC 14882:2011)
• C++14 (ISO/IEC 14882:2014)
• C++17 (ISO/IEC 14882:2017)
• C++20 (ISO/IEC 14882:2020)
• A Glimpse into the Future: C++23 and Beyond
• Conclusion: Choosing the Right Standard
• Online Compilers for Experimentation
• References

Introduction to C++ Standards

C++ standards are established by the International Organization for Standardization (ISO) and its Working Group 21 (WG21), ensuring uniformity and backwards compatibility. Each standard brings new features, improvements, and deprecations to keep C++ current and powerful.

C++98 (ISO/IEC 14882:1998)

• Release Date: 1998
• Key Features:
  • Namespace scoping
  • Standard Template Library (STL) foundation
  • Exception handling
  • Boolean type bool
• Deprecated Features:
  • None

C++03 (ISO/IEC 14882:2003)

• Release Date: 2003
• Key Features:
  • String class refinements
  • auto keyword for template type deduction
  • Right angle brackets (>>) for stream input
• Deprecated Features:
  • using namespace std; (recommended to avoid)
  • auto_ptr smart pointer (use unique_ptr instead)

C++11 (ISO/IEC 14882:2011)

• Release Date: 2011
• Key Features:
  • Lambda expressions for concise anonymous functions
  • Range-based for loops for cleaner iteration
  • Smart pointers (unique_ptr, shared_ptr) for memory management
  • Move semantics for efficient object transfer
  • Multithreading improvements
• Deprecated Features:
  • No major deprecations

C++14 (ISO/IEC 14882:2014)

• Release Date: 2014
• Key Features:
  • Generic lambdas for more flexible function pointers
  • decltype for automatic type deduction
  • constexpr for compile-time calculations
  • Type traits for template metaprogramming
• Deprecated Features:
  • No major deprecations

C++17 (ISO/IEC 14882:2017)

• Release Date: 2017
• Key Features:
  • Variable templates for template metaprogramming enhancements
  • Fold expressions for succinct aggregations
  • Parallel algorithms for optimized multithreading
• Deprecated Features:
  • auto_ptr (strongly discouraged)
  • Implicit this captures in lambdas (prefer explicit captures)

C++20 (ISO/IEC 14882:2020)

• Release Date: 2020
• Key Features:
  • Concepts for advanced template type checking
  • Modules for better code organization
  • Coroutines for lightweight asynchronous programming
  • Range-v3 library for more powerful iterators
• Deprecated Features:
  • Traditional switch statement without break (prefer enum-switch)
  • Unrestricted friend declarations (use appropriate access control)

A Glimpse into the Future: C++23 and Beyond

• The next standard, C++23, is expected in 2023 and will likely offer improvements in modules, concepts, coroutines, and more.
• C++26 and beyond hold promise for continued evolution, addressing areas like concurrency, metaprogramming, and performance.