rust string reader

string_reader.rs

use std::slice::Iter;

pub struct StringReader<'a> {
    iter: Iter<'a, u8>,
    len: usize,
    pos: usize,
}

impl<'a> StringReader<'a> {
    pub fn new(data: &'a str) -> Self {
        Self {
            iter: data.as_bytes().iter(),
            len: data.len(),
            pos: 0,
        }
    }
    pub fn read_line(&mut self) -> Option<String> {
        let mut result = String::new();
        if self.pos >= self.len {
            return None;
        }
        for _ in self.pos..self.len {
            self.pos += 1;
            let c = *self.iter.next().unwrap() as char;
            result.push(c);
            if c == '\n' {
                break;
            }
        }
        return Some(result.trim().to_owned());
    }
}