Hi,
I would like to accomplish
and I do not see why this piece of code does not compile...Code:#include <tr1/functional> #include <iostream> #include <vector> #include <set> #include <algorithm> using namespace std; using namespace tr1; using namespace placeholders; int main() { int ar[] = {0, 1, 2, 3, 4, 5}; vector<int> ivec(ar, ar+6); set<int> iset(ar, ar+6); for_each(ivec.begin(), ivec.end(), bind(&std::set<int>::erase, &iset, _1)); cout << iset.size(); return 0; }
The reason is (assuming there is this tr1/functional header with all the stuff, I used boost::lambda) that set::erase is an overloaded method. You can't deduce template arguments from an overloaded function unless you are more explicit.
(With boost) I did this:
It should also work with a static cast of the function pointer.Code:set<int>::size_type( set<int>::*mp)(const int&) = &set<int>::erase; for_each(ivec.begin(), ivec.end(), bind(mp, &iset, _1));
As you can see it is rather verbous. Whether it pays off is up to you.
I might be wrong.
Quoted more than 1000 times (I hope).Thank you, anon. You sure know how to recognize different types of trees from quite a long way away.
Thank you! I did not think about it and pointers to member functions are not trivial... I'll use this solution with a comment and a good name.
std::tr1::bind is equivalent to boost::bind, it allows to not depend on boost as it is now part of most C++ implementations. TR1 also has shared_ptr and ref, cref (and other things I am not using.)
Although, I'd recommend going for boost for now.
Not all compilers have TR1 implementations.
On the other hand, you can just use boost and it works everywhere.
Originally Posted by Adak
