C++ Syntax: Add new vector to a list - c++

Question

Ok, so this is a bit complicated and my syntax memory sucks...
I have a list which holds vectors of objects called "Plane".
Here:
std::list<std::vector<Plane>> possible_planes;
Plane is a class I made.
What I am trying to do now is add new entries to that.
So something like this:
possible_planes.push_back(std::vector<Plane> new Plane(boundRect[i].area(), center[i]));
And here is where I fail to get the syntax right. What does the correct syntax look like?

Answer 1

You code is declaring a variable in the middle of an expression, as well as dynamically allocating when it should not be. Try this:
possible_planes.push_back(std::vector<Plane>());
possible_planes.back().push_back(Plane(boundRect[i].area(), center[i]));
Note, this could be reduced even more if I knew you were using a C++11 compliant toolchain.

Answer 2

1. first create new vector, then add the plane
possible_planes.push_back(std::vector<Plane>());
possible_planes.back().push_back(Plane(boundRect[i].area(), center[i]));
2. have a function like this one
std::vector<Plane> createNewPlaneVector(Plane& plane) {
std::vector<Plane> result;
result.push_back(plane);
return result;
}
then you can add then new vector in one line
possible_planes.push_back(createNewPlaneVector(Plane(boundRect[i].area(), center[i])));
If you are using C++11 then this gets simpler:
possible_planes.push_back(std::vector<Plane>() { Plane(boundRect[i].area(), center[i]) } );

Answer 3

Maybe try doing it with multiple lines and variables, like this:
vector<Plane> newPlane; // Vector you add to list later
Plane myPlane; // Your object
// Do what you want with your Plane object
newPlane.push_back(myPlane); // Insert your object to vector
possible_planes.push_back(newPlane); // Insert vector to list