Returns true if this is a radical expression, false otherwise.
Returns true if this is a radical expression, false otherwise.
Override this to return the Real resulting from the tree.
Override this to return the Real resulting from the tree.
This folds all ring ops (+, -, *) on constants to constants. This only works on
IntLits for now, asBigInts may be slow.TODO: It may be worth it to fold
BigIntLits for add/subtract, since the space requirement would approximately half.