Understanding C++ Value Categories: lvalue, rvalue, xvalue, std::move, std::forward & Best Practices
summary
Clear, example-driven breakdown of why C++ has five value categories (lvalue, xvalue, prvalue, glvalue, rvalue), how rvalue references plus std::move enable move semantics, and when std::forward (universal/forwarding references, reference collapsing) preserves value category. Shows concrete surprises: const temporaries defeat moves (so std::move can trigger a copy), C++17 mandates guaranteed elision, and move ops should be noexcept. Uses short quizzes and code examples to prove behavior and recommend fixes.
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chapters (9)
- 0:00Introduction and motivation
- 2:02Understanding expressions
- 9:17Historical context and categories
- 16:44The five value categories
- 23:16Categorization and examples
- 36:07Rvalue references
- 37:47Move semantics in practice
- 42:21Universal references and templates
- 50:14Perfect forwarding and best practices
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