To handle "base cases" (the exit condition for recursion).
C++ (TMP) is essentially a "program within a program." It allows you to execute logic during compilation rather than at runtime, using the compiler as an interpreter to generate optimized code. 1. The Core Mechanism: Functional Programming C Template Metaprogramming Concepts
Concepts are the modern evolution of TMP. Instead of relying on complex SFINAE "hacks" to restrict templates, allow you to explicitly define requirements for template arguments using the requires keyword. This makes error messages much more readable and the code intent clearer. 6. Variable Templates and constexpr To handle "base cases" (the exit condition for recursion)
Uses static constexpr to return a result (e.g., calculating a factorial at compile time). The Core Mechanism: Functional Programming Concepts are the
This is a fundamental rule used to "sift" through template overloads. If a template fails to compile during the substitution of types, the compiler doesn't crash—it simply ignores that specific overload and looks for another that works. This is the backbone of and library-level introspection. 4. Type Traits