cpp / expert
Snippet
Metaprogramming Control Flow via Function Specialization
Leveraging SFINAE (Substitution Failure Is Not An Error) and std::enable_if, this snippet demonstrates compile-time control flow branching. It allows the compiler to select different function implementations based on the underlying data types, effectively removing runtime branching overhead.
snippet.cpp
cpp
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#include <type_traits>#include <iostream>template <typename T>std::enable_if_t<std::is_integral_v<T>, void>process_data(T value) {std::cout << "Integral processing: " << value << std::endl;}template <typename T>std::enable_if_t<std::is_floating_point_v<T>, void>process_data(T value) {std::cout << "Precision processing: " << value << std::endl;}template <typename T>auto handle(T&& val) -> decltype(process_data(std::forward<T>(val))) {return process_data(std::forward<T>(val));}
Breakdown
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std::enable_if_t<std::is_integral_v<T>, void>
Ensures this function overload is only visible to the compiler if T is an integer type.
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T&& val ... std::forward<T>(val)
Implements perfect forwarding to preserve the value category (lvalue/rvalue) of the input.