public virtual ulong GetHash() { ulong hashCode = 0uL; unchecked { if (LeftOperand != null) { hashCode += 1000000007 * LeftOperand.GetHash(); } if (RightOperand != null) { hashCode += 1000000009 * RightOperand.GetHash(); } hashCode += 1000000021 * (ulong)OperatorToken; } return(hashCode); }