Webtagr - Technology News Summarizer

C++ Metaprogramming Tricks: Optimizing Variant Access Performance

2025-05-14

This article explores optimizing `std::variant` access performance in C++ using metaprogramming techniques, aiming for efficiency comparable to hand-written `switch` statements. Several approaches are compared, including jump tables, dispatch tables, macros, recursive `switch`, and short-circuiting folds, analyzing their pros, cons, and compiler optimization strategies. Ultimately, a solution combining short-circuiting folds and the anticipated C++26 expansion statements is presented, achieving efficient generic access and avoiding performance bottlenecks.

C++ Metaprogramming: Ditching IILEs in Favor of Expansion Statements and Structured Bindings

2025-03-26

This blog post explores how to streamline C++ metaprogramming, reducing reliance on Immediately Invoked Lambda Expressions (IILEs) by leveraging the `expand` helper, expansion statements, and structured bindings. It details element-wise expansion, early returns, and returning values, showing how to transform arbitrary ranges into packs for efficient compile-time data manipulation. These techniques significantly improve code readability and maintainability, avoiding verbose coding practices.

Order-Independent Keyword Arguments in C++26 using Reflection

2025-02-11

This blog post explores implementing order-independent keyword arguments for C++ using C++26's proposed reflection features. The author stumbled upon this technique while experimenting with reflection and shares it as a compelling demonstration of the power of these features. The post contrasts this approach with prior, less elegant solutions, including designated initializers and helper objects. The core of the post details how to leverage reflection to achieve order-independent and optional keyword arguments, providing complete code examples and explanations. This includes handling lambda expression captures and extending the fmt library for enhanced formatting capabilities.