Calling multiple functions for an input

Simply put, when I opt for a data-driven design, I separate the data from the behavior. Given an input as

struct Input {
    int value;

I pass it to some components that operate on it. I… call some functions.

void set(Input& in, int value) { input.value = value; }
void reset(Input& in) { input.value = 0; }

Input in{};
set(in, 2);


Because life is better with patterns, I’d want to have independent and configurable functions and a clear intent of their role and usage. Short story, a way to do this is a list of functions to be called with an input.

template<typename T, typename... Fs>
void apply(T& in, Fs&&... fs) {
    (fs(in), ...);

I’ve used the C++17 fold expression to unpack the template parameters (the list of functions). Continue reading Calling multiple functions for an input