rt_graph/null_data_source.rs
1use crate::{DataSource, Point, Result};
2
3/// A `DataSource` that returns no data points.
4#[derive(Debug)]
5pub struct NullDataSource;
6
7impl DataSource for NullDataSource {
8 fn get_data(&mut self) -> Result<Vec<Point>> {
9 Ok(vec![])
10 }
11
12 fn get_num_values(&self) -> Result<usize> {
13 Ok(1)
14 }
15}
16
17impl NullDataSource {
18 /// Constructs a new instance of `NullDataSource`.
19 pub fn new() -> NullDataSource {
20 NullDataSource
21 }
22}