Question

I am having trouble setting up my functions in a class when I want to have a function return a vector of type struct which I have just defined. Compiler gives a “Use of undeclared identifier” error.

In the .h file: (no errors given)

struct workingPoint;

public:

vector<workingPoint>calculateWorkingPointCloud();

And in the .cpp file:

struct DeltaKinematics::workingPoint {
    int x, y, z;
    //more stuff to come
};

vector<workingPoint> DeltaKinematics::calculateWorkingPointCloud(){ //error here is "Use of undeclared identifier 'workingPoint'

}

It seems that the compiler doesn’t know what a workingPoint is, despite the fact it is declared before the function?

Answer 1

It is simply a problem of the lookup. You need to fully qualify the name, e.g.
vector<DeltaKinematics::workingPoint> DeltaKinematics::calculateWorkingPointCloud(){...

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