Access Pecularities with Pairs in std::Map

[g0dwyn]

Hey everyone,

This has always confused me. I'm using the default STL implementation provided by the MinGW suite, and when I use an iterator to the map, I can access the key and value if I don't dereference the iterator, like so:

using namespace std;
map<string,int> myMap;
...
map<string,int>::iterator it;
for (it = myMap.begin();it !=myMap.end();++it)
{
   cout << "key is: " << it->first << endl;
   cout << "value is: " << it->second << endl;
}

However, if I deref the iterator beforehand, as seen in this site's STL reference quide ([url]http://cplusplus.com/reference/stl/map/begin.html[/url]), I get a compile-time error stating:

error: 'struct std::_Rb_tree_iterator<std::pair<const std::string, int> >' has no member named 'second'

It's also worth noting that my STL doesn't include the Pair class - I can't #include <pair> . Yet Map and non deref'd iterators work fine. Any ideas?

[jsmith]

#include <utility> for std::pair

operator* and operator-> on map iterators do two different things.