# actix_web::State - Rust
API documentation for the Rust `State` struct in crate `actix_web`.
Keywords: rust, rustlang, rust-lang, State

# [−] [src] Struct actix_web::State

    pub struct State<S>(_);

Access an application state

`S` - application state type

## Example

    #[macro_use] extern crate serde_derive;
    use actix_web::{http, App, Path, State};

    /// Application state
    struct MyApp {
        msg: &'static str,
    }

    #[derive(Deserialize)]
    struct Info {
        username: String,
    }

    /// extract path info using serde
    fn index(state: State<MyApp>, path: Path<Info>) -> String {
        format!("{} {}!", state.msg, path.username)
    }

    fn main() {
        let app = App::with_state(MyApp { msg: "Welcome" }).resource(
            "/{username}/index.html", // <- define path parameters
            |r| r.method(http::Method::GET).with(index),
        ); // <- use `with` extractor
    }

## Trait Implementations

###

`impl<S> FromRequest<S> for State<S>`

[src]

#### `type Config = ()`

Configuration for conversion process

#### `type Result = State<S>`

Future that resolves to a Self

####

`fn from_request(req: &HttpRequest<S>, _: &Self::Config) -> Self::Result`

[src]

Convert request to a Self

####

`fn extract(req: &HttpRequest<S>) -> Self::Result`

[src]

Convert request to a Self Read more

###

`impl<S> Deref for State<S>`

[src]

#### `type Target = S`

The resulting type after dereferencing.

####

`fn deref(&self) -> &S`

[src]

Dereferences the value.

## Auto Trait Implementations

###

`impl<S> !Send for State<S>`

###

`impl<S> !Sync for State<S>`

## Blanket Implementations

###

`impl<T> From for T`

[src]

####

`fn from(t: T) -> T`

[src]

Performs the conversion.

###

`impl<T, U> Into for T where U: From<T>,`

[src]

####

`fn into(self) -> U`

[src]

Performs the conversion.

###

`impl<T, U> TryFrom for T where T: From<U>,`

[src]

#### `type Error = !`

🔬 This is a nightly-only experimental API. (`try_from`)

The type returned in the event of a conversion error.

####

`fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`

[src]

🔬 This is a nightly-only experimental API. (`try_from`)

Performs the conversion.

###

`impl<T> Borrow for T where T: ?Sized,`

[src]

####

`fn borrow(&self) -> &T`

[src]

Immutably borrows from an owned value. Read more

###

`impl<T> BorrowMut for T where T: ?Sized,`

[src]

####

`fn borrow_mut(&mut self) -> &mut T`

[src]

Mutably borrows from an owned value. Read more

###

`impl<T, U> TryInto for T where U: TryFrom<T>,`

[src]

#### `type Error = <U as TryFrom<T>>::Error`

🔬 This is a nightly-only experimental API. (`try_from`)

The type returned in the event of a conversion error.

####

`fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`

[src]

🔬 This is a nightly-only experimental API. (`try_from`)

Performs the conversion.

###

`impl<T> Any for T where T: 'static + ?Sized,`

[src]

####

`fn get_type_id(&self) -> TypeId`

[src]

🔬 This is a nightly-only experimental API. (`get_type_id`)

this method will likely be replaced by an associated static

Gets the `TypeId` of `self`. Read more

###

`impl<T> Erased for T`

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