Rust word usage counter

wcount.rs

#![feature(phase)]
#[phase(plugin)]
extern crate regex_macros;
extern crate regex;
use regex::Regex;
use std::ascii::AsciiExt;
use std::collections::{HashMap};
use std::collections::hash_map::Entry::{Vacant, Occupied};
use std::io::{BufferedReader, File};

static WORD_PATTERN: Regex = regex!(r"(\w)+('\w+)?");

struct Item {
    word: String,
    count: int,
}

fn main() {
    let content = get_content();
    let mut map: HashMap<String, int> = HashMap::new();

    for word in content.into_iter() {
        match map.entry(word) {
            Occupied(mut entry) => *entry.get_mut() += 1,
            Vacant(entry) => { entry.set(1); },
        };
    }

    let mut items = Vec::new();
    for (key, val) in map.iter() {
        items.push(Item { word: key.to_string(), count: *val });
    }
    items.sort_by(|a, b| a.word.cmp(&b.word));
    items.sort_by(|a, b| b.count.cmp(&a.count));
    for i in items.iter() {
        println!("{}: {}", i.word, i.count);
    }
}

fn get_content() -> Vec<String> {
    let args = std::os::args();
    let text = File::open(&Path::new(&args[1])).read_to_string().unwrap();
    WORD_PATTERN.captures_iter(text.as_slice())
        .map(|cap| cap.at(0).to_ascii_upper())
        .collect()
}