Erasing items from an STL list

Question

I want to make a function which moves items from one STL list to another if they match a certain condition.

This code is not the way to do it. The iterator will most lik

Answer 1

std::list::iterator endMatching =
    partition(myList.begin(), myList.end(), myCondition);
myOtherList.splice(myOtherList.begin(), myList, endMatching, myList.end());

Note that partition() gives you enough to discriminate matching objects from non matching ones. (list::splice() is cheap however)

See the following code on a concrete case inspired from Now to remove elements that match a predicate?

#include 
#include 
#include 
#include 
#include 
#include 

using namespace std;

class CPred : public unary_function
{
public:
        CPred(const string& arString)
                :mString(arString)
        {
        }

        bool operator()(const string& arString) const
        {
                return (arString.find(mString) == std::string::npos);
        }
private:
        string mString;
};

int main()
{
        list Strings;

        Strings.push_back("213");
        Strings.push_back("145");
        Strings.push_back("ABC");
        Strings.push_back("167");
        Strings.push_back("DEF");

        cout << "Original list" << endl;
        copy(Strings.begin(), Strings.end(),ostream_iterator(cout,"\n"));

        CPred Pred("1");

        // Linear. Exactly last - first applications of pred, and at most (last - first)/2 swaps. 
        list::iterator end1 =
        partition(Strings.begin(), Strings.end(), Pred);

        list NotMatching;

        // This function is constant time. 
        NotMatching.splice(NotMatching.begin(),Strings, Strings.begin(), end1); 

        cout << "Elements matching with 1" << endl;
        copy(Strings.begin(), Strings.end(), ostream_iterator(cout,"\n"));

        cout << "Elements not matching with 1" << endl;
        copy(NotMatching.begin(), NotMatching.end(), ostream_iterator(cout,"\n"));

        return 0;
}