rust - 解决 Rust 中的导入
问题描述
我在从crates.io导入rand crate 时遇到问题。添加行 rand="0.8.3" 然后为项目运行命令cargo build后,它一直显示相同的错误:
error[E0432]: unresolved import `rand`
--> main.rs:1:5
|
1 | use rand::Rng;
| ^^^^ maybe a missing crate `rand`?
error[E0433]: failed to resolve: use of undeclared crate or module `rand`
--> main.rs:4:25
|
4 | let secret_number = rand::thread_rng().gen_range(1..=11);
| ^^^^ use of undeclared crate or module `rand`
error: aborting due to 2 previous errors
cargo.toml文件_
[package]
name = "roller"
version = "0.1.0"
authors = ["User"]
edition = "2018"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
rand = "0.8.3"
基本上,最简单的可重现示例就是这行代码:
use rand::Rng;
fn main(){
let secret_number = rand::thread_rng().gen_range(1..=11);
print!("{}",secret_number);
}
它出什么问题了?
以防万一:
**cargo.lock** 文件:
# This file is automatically @generated by Cargo.
# It is not intended for manual editing.
[[package]]
name = "cfg-if"
version = "1.0.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
[[package]]
name = "getrandom"
version = "0.2.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "c9495705279e7140bf035dde1f6e750c162df8b625267cd52cc44e0b156732c8"
dependencies = [
"cfg-if",
"libc",
"wasi",
]
[[package]]
name = "libc"
version = "0.2.86"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "b7282d924be3275cec7f6756ff4121987bc6481325397dde6ba3e7802b1a8b1c"
[[package]]
name = "ppv-lite86"
version = "0.2.10"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "ac74c624d6b2d21f425f752262f42188365d7b8ff1aff74c82e45136510a4857"
[[package]]
name = "rand"
version = "0.8.3"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "0ef9e7e66b4468674bfcb0c81af8b7fa0bb154fa9f28eb840da5c447baeb8d7e"
dependencies = [
"libc",
"rand_chacha",
"rand_core",
"rand_hc",
]
[[package]]
name = "rand_chacha"
version = "0.3.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e12735cf05c9e10bf21534da50a147b924d555dc7a547c42e6bb2d5b6017ae0d"
dependencies = [
"ppv-lite86",
"rand_core",
]
[[package]]
name = "rand_core"
version = "0.6.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "34cf66eb183df1c5876e2dcf6b13d57340741e8dc255b48e40a26de954d06ae7"
dependencies = [
"getrandom",
]
[[package]]
name = "rand_hc"
version = "0.3.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "3190ef7066a446f2e7f42e239d161e905420ccab01eb967c9eb27d21b2322a73"
dependencies = [
"rand_core",
]
[[package]]
name = "roller"
version = "0.1.0"
dependencies = [
"rand",
]
[[package]]
name = "wasi"
version = "0.10.2+wasi-snapshot-preview1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "fd6fbd9a79829dd1ad0cc20627bf1ed606756a7f77edff7b66b7064f9cb327c6"
解决方案
在 Cargo.toml 文件中添加行:
[dependencies]
rand="0.3.14"
并重建项目!
它适用于这些版本:
锈病 1.53.0
货物 1.53.0
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