Function intspan::reader

pub fn reader(input: &str) -> Box<dyn BufRead>

use std::io::BufRead;
let reader = intspan::reader("tests/spanr/S288c.chr.sizes");
let mut lines = vec![];
for line in reader.lines() {
    lines.push(line);
}
assert_eq!(lines.len(), 16);

let reader = intspan::reader("tests/spanr/S288c.chr.sizes");
assert_eq!(reader.lines().collect::<Vec<_>>().len(), 16);