How can I declare and define multiple variables in one line using C++?

Question

I always though that if I declare these three variables that they will all have the value 0

int column, row, index = 0;

Bu

Answer 1

As others have mentioned, from C++17 onwards you can make use of structured bindings for multiple variable assignments.

Combining this with std::array and template argument deduction we can write a function that assigns a value to an arbitrary number of variables without repeating the type or value.

#include 
#include 

template  auto assign(T value)
{
    std::array out;
    out.fill(value);
    return out;
}

int main()
{
    auto [a, b, c] = assign<3>(1);

    for (const auto& v : {a, b, c})
    {
        std::cout << v << std::endl;
    }

    return 0;
}

Demo