indexing a string in rust.

rust_indexing.rs

use std::fs::File;
use std::io::prelude::*;
use std::io::SeekFrom;
use std::fs::OpenOptions;

#[derive(Debug)]
struct Seg(usize, usize);

impl Seg {
    fn contains(&self, text:&[u8], term:&[u8]) -> bool {
        let mut mode = false;
        let mut idx = 0;
        for i in self.0..(self.1 + 1) {
            println!("i is {:?}", i);
            if mode {
                if text[i] == term[idx] {
                    idx += 1;
                    if idx == term.len() {
                        return true;
                    }
                } else {
                    mode = false;
                    idx = 0;
                }
            } else {
                if text[i] == term[0] {
                    println!("Got begin");
                    mode = true;
                    idx += 1;
                }
            }
        }
        false
    }
}

fn get_indexes(text:&[u8], delim:u8) -> Vec<Seg> {
    let mut v = Vec::new();
    let mut last_idx = 0;
    for i in 0..text.len() {
        if text[i] == delim && i - last_idx > 1 {
            v.push(Seg(last_idx + 1, i - 1));
            last_idx = i;
        }
    }
    if (text.len() - 1 - last_idx) > 0 {
        v.push(Seg(last_idx + 1, text.len() - 1));
    }
    return v;
}


fn main() {
    let foo = "\nfoobar\nfoobar\n4".to_string();
    let segs = get_indexes(foo.as_bytes(), b'\n');
    println!("{:?}", segs);
    println!("{}", segs[0].contains(foo.as_bytes(),b"foobar"));
}