presto-main/src/main/java/io/prestosql/operator/scalar/RowIndeterminateOperator.java/RowIndeterminateOperator/specialize
class RowIndeterminateOperator:    @Override
    public ScalarFunctionImplementation specialize(BoundVariables boundVariables, int arity, Metadata metadata)
    {
        checkArgument(arity == 1, "Expected arity to be 1");
        Type type = boundVariables.getTypeVariable("T");
        Class<?> indeterminateOperatorClass = generateIndeterminate(type, metadata);
        MethodHandle indeterminateMethod = methodHandle(indeterminateOperatorClass, "indeterminate", type.getJavaType(), boolean.class);
        return new ScalarFunctionImplementation(
                false,
                ImmutableList.of(valueTypeArgumentProperty(USE_NULL_FLAG)),
                indeterminateMethod);
    }