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

IMHO it's more straight forward and more readable to use a for loop with an if inside it. However, if this is annoying for you, you could use a for_each_if like the one below:

template 
void for_each_if(Iter first, Iter last, Pred p, Op op) {
  while(first != last) {
    if (p(*first)) op(*first);
    ++first;
  }
}

Usecase:

std::vector v {10, 2, 10, 3};
for_each_if(v.begin(), v.end(), [](int i){ return i > 5; }, [](int &i){ ++i; });

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