我想不通为什么我的本地var线does not live long enough
。你可以看到我的代码在下面。它在Rust的游乐场上工作。错误:`线`活得不够长,但在操场上没问题
我可能有这个问题的想法:我使用一个结构(加载是这个结构的函数)。由于我想将行的结果存储在结构的成员中,因此可能是问题所在。但我不明白该怎么做才能解决这个问题。
pub struct Config<'a> {
file: &'a str,
params: HashMap<&'a str, &'a str>
}
impl<'a> Config<'a> {
pub fn new(file: &str) -> Config {
Config { file: file, params: HashMap::new() }
}
pub fn load(&mut self) ->() {
let f = match fs::File::open(self.file) {
Ok(e) => e,
Err(e) => {
println!("Failed to load {}, {}", self.file, e);
return;
}
};
let mut reader = io::BufReader::new(f);
let mut buffer = String::new();
loop {
let result = reader.read_line(&mut buffer);
if result.is_ok() && result.ok().unwrap() > 0 {
let line: Vec<String> = buffer.split("=").map(String::from).collect();
let key = line[0].trim();
let value = line[1].trim();
self.params.insert(key, value);
}
buffer.clear();
}
}
...
}
而且我得到这个错误:
src/conf.rs:33:27: 33:31 error: `line` does not live long enough
src/conf.rs:33 let key = line[0].trim();
^~~~
src/conf.rs:16:34: 41:6 note: reference must be valid for the lifetime 'a as defined on the block at 16:33...
src/conf.rs:16 pub fn load(&mut self) ->() {
src/conf.rs:17 let f = match fs::File::open(self.file) {
src/conf.rs:18 Ok(e) => e,
src/conf.rs:19 Err(e) => {
src/conf.rs:20 println!("Failed to load {}, {}", self.file, e);
src/conf.rs:21 return;
...
src/conf.rs:31:87: 37:14 note: ...but borrowed value is only valid for the block suffix following statement 0 at 31:86
src/conf.rs:31 let line: Vec<String> = buffer.split("=").map(String::from).collect();
src/conf.rs:32
src/conf.rs:33 let key = line[0].trim();
src/conf.rs:34 let value = line[1].trim();
src/conf.rs:35
src/conf.rs:36 self.params.insert(key, value);
...
添加结构定义,以便我们可以知道'self.params'类型。 – malbarbo
完成了,我加了很多结构 – Kadok