1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! Maps are collections of unique keys with corresponding values, and sets are
12 //! just unique keys without a corresponding value.
14 //! This crate defines the `TreeMap` and `TreeSet` types. Their keys must implement `Ord`.
16 //! `TreeMap`s are ordered.
21 //! use std::collections::TreeSet;
23 //! let mut tree_set = TreeSet::new();
25 //! tree_set.insert(2i);
26 //! tree_set.insert(1i);
27 //! tree_set.insert(3i);
29 //! for i in tree_set.iter() {
30 //! println!("{}", i) // prints 1, then 2, then 3