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//! Types and traits for request parsing and handling.
mod request;
mod from_param;
mod from_request;
#[cfg(test)]
mod tests;
pub use self::request::Request;
pub use self::from_request::{FromRequest, Outcome};
pub use self::from_param::{FromParam, FromSegments};
#[doc(inline)]
pub use crate::response::flash::FlashMessage;
pub(crate) use self::request::ConnectionMeta;
crate::export! {
/// Store and immediately retrieve a vector-like value `$v` (`String` or
/// `Vec<T>`) in `$request`'s local cache using a locally generated
/// anonymous type to avoid type conflicts.
///
/// Unlike `local_cache_once`, this macro's generated code _always_ returns
/// a unique reference to request-local cache.
///
/// # Note
///
/// The value `$v` must be of type `String` or `Vec<T>`, that is, a type
/// that implements the sealed trait [`Shareable`](crate::form::Shareable)bb).
///
/// # Example
///
/// ```rust
/// use rocket::request::{local_cache, local_cache_once};
/// # let c = rocket::local::blocking::Client::debug_with(vec![]).unwrap();
/// # let request = c.get("/");
///
/// // The first store into local cache for a given type wins.
/// for i in 0..4 {
/// assert_eq!(request.local_cache(|| i.to_string()), "0");
/// }
///
/// // This shows that we cannot cache different values of the same type; we
/// // _must_ use a proxy type. To avoid the need to write these manually, use
/// // `local_cache!`, which generates one of the fly.
/// for i in 0..4 {
/// assert_eq!(local_cache!(request, i.to_string()), i.to_string());
/// }
///
/// // Note that while `local_cache_once!` generates a new type for the
/// // _macro_ invocation, that type is the same per run-time invocation, so
/// // all "calls" to `local_cache_once!` on the same line return the same
/// // reference for a given request.
/// for i in 1..4 {
/// // Note that this is `1`, so _not_ the `String` from line 4.
/// assert_eq!(local_cache_once!(request, i.to_string()), "1");
/// }
/// ```
macro_rules! local_cache {
($request:expr, $v:expr $(,)?) => ({
struct Local<T: $crate::form::Shareable>($crate::form::SharedStack<T>);
let stack = $request.local_cache(|| Local($crate::form::SharedStack::new()));
stack.0.push_owned($v)
})
}
}
crate::export! {
/// Store and immediately retrieve a value `$v` in `$request`'s local cache
/// using a locally generated anonymous type to avoid type conflicts.
///
/// The code generated by this macro is expected to be invoked at-most once
/// per-request. This is because while `local_cache_once!` generates a new
/// type for the _macro_ invocation, that type is the same per run-time
/// invocation. Thus, for a given request, a `local_cache_once!` invocation
/// always returns the same reference.
///
/// To get a unique request-local reference to string-like values, use
/// [`local_cache!`] instead.
///
/// # Example
///
/// ```rust
/// use rocket::request::local_cache_once;
/// # let c = rocket::local::blocking::Client::debug_with(vec![]).unwrap();
/// # let request = c.get("/");
///
/// // The first store into local cache for a given type wins.
/// assert_eq!(request.local_cache(|| String::from("hello")), "hello");
///
/// // The following returns the cached, previously stored value for the type.
/// assert_eq!(request.local_cache(|| String::from("goodbye")), "hello");
///
/// // This shows that we cannot cache different values of the same type;
/// // we _must_ use a proxy type. To avoid the need to write these manually,
/// // use `local_cache_once!`, which generates one of the fly.
/// assert_eq!(local_cache_once!(request, String::from("hello")), "hello");
/// assert_eq!(local_cache_once!(request, String::from("goodbye")), "goodbye");
///
/// // But a macro invocation for the same request always resolves to the
/// // first reference as the unique type is generated at compile-time.
/// for i in 1..4 {
/// assert_eq!(local_cache_once!(request, i.to_string()), "1");
/// }
/// ```
macro_rules! local_cache_once {
($request:expr, $v:expr $(,)?) => ({
struct Local<T>(T);
&$request.local_cache(move || Local($v)).0
})
}
}