Alan M. Carroll wrote:

1) find_if expects a unary functor returning bool. You are passing a binary functor. _1 will be the element in the vector, but what did you think would be passed for _2?

2) CompareByVal should either be static or not have the pointer argument. There's no need to pass "this" by hand. The first argument to the bind of a method is an explicit "this" but the method is just a method, it is not aware that it has been called from Boost.bind.

Or, expressed in code, this is what you might want: ----------------------------------------------------------- #include <algorithm> #include <string> #include <vector> #include #include <algorithm> #include <string> #include <vector> #include template<typename T> class A { T _val; public: A(T val) : _val(val){}; T Val() {return _val;} const bool CompareByVal(const int iType, const T& ofval) const { return ((iType == 1) && (_val == ofval)); } }; int main(int argc, char** argv) // My compiler did not like _TCHAR { std::vector a; std::find_if (a.begin(), a.end(), boost::bind(&A<int>::CompareByVal, _1, 1, 2)); } --------------------------------------------- This finds those A objects with _val==2 under the condition that iType==1. Btw, with _val being of type int* in the original example, I would consider any found instances pretty dubious ;-) Regards, Roland