如何在稳定的Rust中使用std :: collections :: BitSet？

Question

I am trying to use BitSet data structure, but it gives me a compile error saying it was not able to find the BitSet. Has std::collections::BitSet been released in the stable version?

use std::collections::BitSet;

fn main() {
    println!("Hello, world!");
}

Produces the error:

error[E0432]: unresolved import `std::collections::BitSet`
 --> src/main.rs:1:5
  |
1 | use std::collections::BitSet;
  |     ^^^^^^^^^^^^^^^^^^^^^^^^ no `BitSet` in `collections`

Answer 1

It seems that BitSet existed in Rust 1.3.0, which is very old , but was already deprecated at that time and finally removed by this commit .

Instead, you can use bit-set crate , as suggested by the deprecation message above. There's also documentation .

extern crate bit_set;

use bit_set::BitSet;

fn main() {
    let mut s = BitSet::new();
    s.insert(32);
    s.insert(37);
    s.insert(3);
    println!("s = {:?}", s);
}

You'll have to add a dependency to the bit-set crate in some way. It's easy if you're using Cargo:

[package]
name = "foo"
version = "0.1.0"
authors = ["Foo Bar <foo@example.com>"]

[dependencies]
bit-set = "0.4.0" # Add this line

If you're using the official Rust Playground , you can automatically use bit-set , because it is one of the top 100 downloaded crates or a dependency of one of them.