title: C++ - "Expression must be modifiable lvalue"
body: <p>The following code gives this error and I for the life of me can not understand why. Any help would me much appreciated.</p>
  
  <pre><code>jdn_t julian_to_jdn(year_t year, month_t month, day_t day)
  {
      double a = (14 - month) / 12;
      year = year + 4800 - a;
      month = month + (12 * a) - 3;
      return day + (153 * month + 2) / 5 + 365 * year + year / 4 = 32083.5;
  }
  </code></pre>
  
  <p>Error   8   error C2106: '=' : left operand must be l-value C:\Users\Italo\Documents\F14 CPA Fanshawe\C++\Project1Files\8. Calendar (D)\Calendar\julian.cpp 46  1   Calendar</p>