@Test
public void testVariables() {

    QuickstartCqlVisitor v = visitLogic(
            "valueset \"Office Visit\" = ValueSet('2.16.840.1.113883.3.464.1003.101.12.1001')\n" +
            "valueset \"Acute Pharyngitis\" = ValueSet('2.16.840.1.113883.3.464.1003.102.12.1011')\n" +
            "let encounter = [NonOccurrence of Encounter, Performance: \"Office Visit\"]\n" +
            "let pharyngitis = [Condition: \"Acute Pharyngitis\"]");
    Collection<String> varSet = v.getVariables();
    assertEquals(varSet.size(), 2);
    assertTrue(varSet.contains("encounter"));
    assertTrue(varSet.contains("pharyngitis"));
}