presto-main/src/main/java/io/prestosql/type/BooleanOperators.java/BooleanOperators/not
class BooleanOperators:    @SqlType(StandardTypes.BOOLEAN)
    @ScalarFunction(hidden = true) // TODO: this should not be callable from SQL
    public static boolean not(@SqlType(StandardTypes.BOOLEAN) boolean value)
    {
        return !value;
    }