c++ regex_search not returning 3 like expected [duplicate]

This question already has an answer here:

• How to match multiple results using std::regex 6 answers

I want to parse the classes from a string, but for some reason the regex method I'm using is not working. Is there something in my regex expression that I don't understand?

I've tried using regex_search("class[^;]+\{").

My Code:

//Use regex matching to find start locations of classes
regex rClass("class[^;]+\\{");
smatch matchClass;
regex_search(wholeFile, matchClass, rClass);
for(int i=0; i<matchClass.size(); i++){

wholeFile string:

#ifndef SIMPLE_H_
#define SIMPLE_H_

class Simple
{
    public:
    Simple();
    struct thing{
        int thingy2;
    };
    virtual unsigned int* TestMe(int& ptr, int hi) const;
    const DepthMap_C& GetDepthMap();
    frameset wait_for_frames(unsigned int timeout_ms = 5000) const{
        rs2_error* e = nullptr;
        frame f(rs2_pipeline_wait_for_frames(_pipeline.get(), timeout_ms, &e));
        error::handle(e);

        return frameset(f);
    }
    private:
    thingy thing;
};

class SimpleA
{
public:
    Simple();
    int foo(int x, double z)
    const DepthMap_C& GetDepthMap();
private:
};

class SimpleB
{
public:
    Simple();
    const DepthMap_C& GetDepthMap();
private:
    purple person;
    peopleeater a;
};

#endif

I expect matchClass.size() to return 3, but I only get 1...