摘要: 环境 Time 2022-03-25 Rust 1.59.0 示例 or fn main() { let result: Result<u32, u32> = Ok(44); println!("{:?}", result.or(Err(4))); } or_else fn main() { let 阅读全文
posted @ 2022-05-28 13:45 jiangbo4444 阅读(50) 评论(0) 推荐(0)
摘要: 环境 Time 2022-03-25 Rust 1.59.0 示例 as_deref fn main() { let result: Result<String, u32> = Ok("ok".to_owned()); let result: Result<&str, &u32> = result. 阅读全文
posted @ 2022-05-28 13:44 jiangbo4444 阅读(46) 评论(0) 推荐(0)
摘要: 环境 Time 2022-03-24 Rust 1.59.0 示例 is_ok fn main() { let result: Result<i32, &str> = Ok(44); println!("{:?}", result.is_ok()); } is_err fn main() { let 阅读全文
posted @ 2022-05-28 13:42 jiangbo4444 阅读(56) 评论(0) 推荐(0)
摘要: 环境 Time 2022-03-23 Rust 1.59.0 示例 find_map fn main() { let vec = ["lol", "NaN", "2", "5"]; let result: Option<i32> = vec.iter().find_map(|s| s.parse() 阅读全文
posted @ 2022-05-28 13:38 jiangbo4444 阅读(59) 评论(0) 推荐(0)
摘要: 环境 Time 2022-03-23 Rust 1.59.0 示例 collect fn main() { let vec = vec![0, 1, 2, 3, 4]; let doubled: Vec<_> = vec.iter().map(|e| e * 2).collect(); for el 阅读全文
posted @ 2022-05-28 13:00 jiangbo4444 阅读(94) 评论(0) 推荐(0)
摘要: 环境 Time 2022-03-22 Rust 1.59.0 示例 take_while 在找到返回 false 的值后,忽略剩余所有元素。 fn main() { let vec = vec![0, 1, 2, 3, 4]; vec.iter() .take_while(|&e| e % 2 == 阅读全文
posted @ 2022-05-28 12:58 jiangbo4444 阅读(143) 评论(0) 推荐(0)
摘要: 环境 Time 2022-03-22 Rust 1.59.0 示例 for_each 和 for 循环类型,遍历每个元素。 fn main() { let vec = vec![0, 1, 2, 3, 4]; vec.iter().for_each(|e| println!("{e}")); } m 阅读全文
posted @ 2022-05-28 12:57 jiangbo4444 阅读(219) 评论(0) 推荐(0)
摘要: 环境 Time 2022-03-22 Rust 1.59.0 示例 iter 生成一个迭代器,可变版本 iter_mut,所有权版本 into_iter。 fn main() { let vec = vec![0, 1, 2, 3, 4]; let iter = vec.iter(); printl 阅读全文
posted @ 2022-05-28 12:55 jiangbo4444 阅读(140) 评论(0) 推荐(0)