internal virtual RareFields WriteRareFields()
 {
     ThrowIfFrozen();
     if (rareFields == null)
     {
         rareFields = new RareFields();
     }
     return(rareFields);
 }
 internal virtual RareFields WriteRareFields()
 {
     ThrowIfFrozen();
     if (rareFields == null) rareFields = new RareFields();
     return rareFields;
 }