code: public void setValueAsEnum(T theValue) {
  		getCoding().clear();
  		if (theValue == null) {
  			return;
  		}
  		getCoding().add(new CodingDt(myBinder.toSystemString(theValue), myBinder.toCodeString(theValue)));
  	}
docs: Sets the {@link #getCoding()} to contain a coding with the code and
  system defined by the given enumerated type, AND clearing any existing
  codings first. If theValue is null, existing codings are cleared and no
  codings are added.
  
  @param theValue
  The value to add, or <code>null</code>