How can I avoid “for” loops with an “if” condition inside them with C++?

Question

With almost all code I write, I am often dealing with set reduction problems on collections that ultimately end up with naive \"if\" conditions inside of them. Here\'s a simple

Answer 1

Also, if you don't care reordering the collection, std::partition is cheap.

#include 
#include 
#include 
#include 

void DoStuff(int i)
{
    std::cout << i << '\n';
}

int main()
{
    using namespace std::placeholders;

    std::vector v {1, 2, 5, 0, 9, 5, 5};
    const int SOMETHING = 5;

    std::for_each(v.begin(),
                  std::partition(v.begin(), v.end(),
                                 std::bind(std::equal_to {}, _1, SOMETHING)), // some condition
                  DoStuff); // action
}