Learning C++ : classes/headers. Doesn't work, and I don't get why.

BagOfValues.cpp

#include "BagOfValues.h"

BagOfValues::BagOfValues() {
  mName = "Jake";
  mWeight = 71.8;
  mAge = 26;
}

BagOfValues.h

#ifndef GUARD_BagOfValues_h
#define GUARD_BagOfValues_h

#include <string>

class BagOfValues {

  public :

    BagOfValues();
    std::string getName() { return mName; }
    double getWeight() { return mWeight; }
    int getAge() { return mAge; }

  private :

    std::string mName;
    double mWeight;
    int mAge;
};

#endif

gistfile1.sh

# THIS IS WRONG

$ clang++ Test.cpp 
/tmp/Test-c7XlKn.o:Test.cpp:function main: error: undefined reference to 'BagOfValues::BagOfValues()'
clang: error: linker command failed with exit code 1 (use -v to see invocation)

# / THIS IS WRONG
# THIS IS RIGHT

$ clang++ -c Test.cpp 
$ clang++ -c BagOfValues.cpp 
$ clang++ Test.o BagOfValues.o
$ ./a.out 
My name is Jake
My age is 26
My weight is 71.8

# / THIS IS RIGHT

Test.cpp

#include "BagOfValues.h"
#include <iostream>
#include <string>

using std::cout;
using std::endl;

int main(){

  BagOfValues *aBag = new BagOfValues;
  cout << "Your name is " << aBag->getName() << endl;
  cout << "Your age is " << aBag->getAge() << endl;
  cout << "Your weight is " << aBag->getWeight() << endl;

  return 0;

}

Using this code, I get a compile error. I don't get why, and I think I just don't understand how the header files work with the classes.

Got it! The code was just fine, the problem was in the linking.