How to have a set of structs in C++

Question

I have a struct which has a unique key. I want to insert instances of these structs into a set. I know that to do this the < operator has to be overloaded so that set can mak

Answer 1

struct Blah
{
    int x;
};

bool operator<(const Blah &a, const Blah &b)
{
    return a.x < b.x;
}

...

std::set my_set;

However, I don't like overloading operator< unless it makes intuitive sense (does it really make sense to say that one Blah is "less than" another Blah?). If not, I usually provide a custom comparator function instead:

bool compareBlahs(const Blah &a, const Blah &b)
{
    return a.x < b.x;
}

...

std::set my_set;