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3. C++20 Concepts and Constraints

Compile-time predicate templates.

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Concepts enforce semantic requirements on template parameters at compile-time, producing clear compiler diagnostic messages rather than pages of template substitution errors.

cpp
template<typename T>
concept Numeric = std::is_integral_v<T> || std::is_floating_point_v<T>;

template<Numeric T>
T add(T a, T b) { return a + b; }

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Check your understanding

1. What problem do C++20 Concepts solve in generic programming?
Provides compile-time constraints and readable compiler errors for template argumentsEnables runtime type checkingDisables templatesReplaces classes
2. Which keyword introduces a concept constraint in template headers?
requiresextendsimplementswhere

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