Peekable Char Iterator

chrpeekiter.rs

use std::iter::Peekable;
use std::str::Chars;

fn main() {
    let s = "Aussonderungsaxiom".to_string();
    let mut bf = Buffer::new(&s);

    println!("First character should be A: {}", bf.peek().expect("q"));
    println!("First char: {}", bf.next().expect("q"));
    println!("Next char: {}", bf.next().expect("q"));
    println!("Peeking the next char: {}", bf.peek().expect("q"));
    println!("Now the next char: {}", bf.next().expect("q"));
}

struct Buffer<'a> {
    pci: Peekable<Chars<'a>>,
}

impl<'a> Buffer<'a> {
    fn new(src: &str) -> Buffer {
        Buffer {
            pci: src.chars().peekable(),
        }
    }

    fn peek(&mut self) -> Option<&char> {
        self.pci.peek()
    }

    fn next(&mut self) -> Option<char> {
        self.pci.next()
    }
}