lifetime

When I try to compile the following code: fn main() { (...) let mut should_end = false; let mut input = Input::new(ctx); input.add_handler(Box::new(|evt| { match evt { &Event::Quit{..} => { should_end = true; } _ => {} } })); while !should_end { input.handle(); } } pub struct Input { handlers: Vec<Box<FnMut(i32)>>, } impl Input { pub fn new() -> Self { Input {handlers: Vec::new()} } pub fn handle(&mut self) { for a in vec![21,0,3,12,1] { for handler in &mut self.handlers { handler(a); } } } pub fn add_handler(&mut self, handler: Box<FnMut(i32)>) { self.handlers.push(handler); } } I get this

I have a struct Foo : struct Foo { v: String, // Other data not important for the question } I want to handle a data stream and save the result into Vec<Foo> and also create an index for this Vec<Foo> on the field Foo::v . I want to use a HashMap<&str, usize> for the index, where the keys will be &Foo::v and the value is the position in the Vec<Foo> , but I'm open to other suggestions. I want to do the data stream handling as fast as possible, which requires not doing obvious things twice. For example, I want to: allocate a String only once per one data stream reading not search the index

I'm trying to sort a Vec<String> using a key function that returns references to the strings in the vector. A contrived example is to use the identity function as key function (which of course is useless, but it's the minimal example to reproduce my problem): fn key(x: &String) -> &String { x } Now given items: Vec<String> , I'd like to be able to do items.sort_by_key(key); This gives the following error: error[E0271]: type mismatch resolving `for<'r> <fn(&std::string::String) -> &std::string::String {main::key} as std::ops::FnOnce<(&'r std::string::String,)>>::Output == _` --> src/main.rs:19

I am confused about ASP or ASP.Net session life time (or life cycle) concepts. More specifically, my confusions are: How does IIS decide when a new session starts and an existing session ends? Especially how does IIS decide whether a session continues or ends when we call redirect code? How can we set session expire time? (Currently I only know to set it through web.config sessionState item.) Is it possible for one session to access another session's variables? Session starts because the request does not contain a session cookie or the session cookie it does contain no longer maps to a session