小编con*_*son的帖子

为什么这段代码可以正常工作

fn main() {
let v1 = vec!["lemonade", "lemon", "type", "lid"];
println!("{:?}", v1.iter().filter(|item| item.starts_with("l")).collect::<Vec<_>>());
}

虽然这段代码给我带来了一个错误，但我有点明白为什么这不起作用并且我知道如何修复它，但我真的不明白它返回什么类型，所以我可以将“_”替换为不那个通用的

fn main() {
let v1 = vec!["lemonade", "lemon", "type", "lid"];
println!("{:?}", v1.iter().filter(|item| item.starts_with("l")).collect::<Vec<&str>>());
}

错误

error[E0277]: a value of type `Vec<&str>` cannot be built from an iterator over elements of 
type `&&str`
--> src\main.rs:3:69
 |
 3    |     println!("{:?}", v1.iter().filter(|item| item.starts_with("l")).collect:: 
 <Vec<&str>>());
 |                                                                     ^^^^^^^ value of type 
 `Vec<&str>` cannot be built from `std::iter::Iterator<Item=&&str>`
 |
 = help: the trait `FromIterator<&&str>` is not implemented for `Vec<&str>`
 = …