找不到“rand”依赖项

Question

找不到“rand”依赖项。

但是货物不起作用。他找到了“rand”库，但它没有安装“rand”库。

我不知道该怎么办。我以为我已经安装了我需要的一切。也许值得重新安装 Rust？

也许我没有安装所有 rust 才能正常工作的软件包？

Cargo.toml

[package]
name = "guessing_game"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
rand = "0.3.14"

main.rs

use std::io;
use rand::Rng;

fn main() {
 println!("Угадайте число!");

 let secret_number = rand::thread_rng().gen_range(1, 101);

 println!("Пожалуйста, введите свою догадку.");

 let mut guess = String::new();

 io::stdin().read_line(&mut guess).expect("Не получилось прочитать строку");

 println!("Вы загадали: {}", guess);
}

---

@负鼠谢谢

Cargo.toml

[package]
name = "guessing_game"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
rand = "0.8.5"

现在他写信给我

C:\Dima\Rust\guessing_game>cargo run
   Compiling guessing_game v0.1.0 (C:\Dima\Rust\guessing_game)
error[E0277]: the trait bound `{integer}: SampleRange<_>` is not satisfied
   --> src\main.rs:7:51
    |
7   |  let secret_number = rand::thread_rng().gen_range(1, 101);
    |                                         --------- ^ the trait `SampleRange<_>` is not implemented for `{integer}`
    |                                         |
    |                                         required by a bound introduced by this call
    |
    = help: the following other types implement trait `SampleRange<T>`:
              std::ops::Range<T>
              RangeInclusive<T>
note: required by a bound in `gen_range`
   --> C:\Users\comp\.cargo\registry\src\index.crates.io-6f17d22bba15001f\rand-0.8.5\src\rng.rs:132:12
    |
129 |     fn gen_range<T, R>(&mut self, range: R) -> T
    |        --------- required by a bound in this associated function
...
132 |         R: SampleRange<T>
    |            ^^^^^^^^^^^^^^ required by this bound in `Rng::gen_range`

error[E0061]: this method takes 1 argument but 2 arguments were supplied
   --> src\main.rs:7:41
    |
7   |  let secret_number = rand::thread_rng().gen_range(1, 101);
    |                                         ^^^^^^^^^  -----
    |                                                    | |
    |                                                    | unexpected argument of type `{integer}`
    |                                                    help: remove the extra argument
    |
note: method defined here
   --> C:\Users\comp\.cargo\registry\src\index.crates.io-6f17d22bba15001f\rand-0.8.5\src\rng.rs:129:8
    |
129 |     fn gen_range<T, R>(&mut self, range: R) -> T
    |        ^^^^^^^^^

Some errors have detailed explanations: E0061, E0277.
For more information about an error, try `rustc --explain E0061`.
error: could not compile `guessing_game` (bin "guessing_game") due to 2 previous errors

C:\Dima\Rust\guessing_game>

Answer 1

@possum 和@Jmb 谢谢

Cargo.toml

[package]
name = "guessing_game"
version = "0.1.0"
edition = "2021"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
rand = "0.8.5"

main.rs

use std::io;
use rand::Rng;

fn main() {
  println!("Угадайте число!");

 let secret_number = rand::thread_rng().gen_range (1..101);

 println!("Пожалуйста, введите свою догадку.");

 let mut guess = String::new();

  io::stdin().read_line(&mut guess).expect("Не получилось прочитать строку");

  println!("Вы загадали: {}", guess);
}

结论

C:\Dima\Rust\guessing_game>cargo run
warning: unused variable: `secret_number`
 --> src\main.rs:7:6
  |
7 |  let secret_number = rand::thread_rng().gen_range (1..101);
  |      ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_secret_number`
  |
  = note: `#[warn(unused_variables)]` on by default

warning: `guessing_game` (bin "guessing_game") generated 1 warning (run `cargo fix --bin "guessing_game"` to apply 1 suggestion)
    Finished dev [unoptimized + debuginfo] target(s) in 0.03s
     Running `target\debug\guessing_game.exe`
Угадайте число!
Пожалуйста, введите свою догадку.
32
Вы загадали: 32