# Struct http::Extensions [−] [src]

    pub struct Extensions { /* fields omitted */ }

A type map of protocol extensions.

`Extensions` can be used by `Request` and `Response` to store extra data derived from the underlying protocol.

## Implementations

### `impl Extensions` [src]

#### `pub fn new() -> Extensions` [src]

Create an empty `Extensions`.

#### `pub fn insert<T: Send + Sync + 'static>(&mut self, val: T) -> Option<T>` [src]

Insert a type into this `Extensions`.

If a extension of this type already existed, it will be returned.

# Example

    let mut ext = Extensions::new();
    assert!(ext.insert(5i32).is_none());
    assert!(ext.insert(4u8).is_none());
    assert_eq!(ext.insert(9i32), Some(5i32));

#### `pub fn get<T: Send + Sync + 'static>(&self) -> Option<&T>` [src]

Get a reference to a type previously inserted on this `Extensions`.

# Example

    let mut ext = Extensions::new();
    assert!(ext.get::<i32>().is_none());
    ext.insert(5i32);

    assert_eq!(ext.get::<i32>(), Some(&5i32));

#### `pub fn get_mut<T: Send + Sync + 'static>(&mut self) -> Option<&mut T>` [src]

Get a mutable reference to a type previously inserted on this `Extensions`.

# Example

    let mut ext = Extensions::new();
    ext.insert(String::from("Hello"));
    ext.get_mut::<String>().unwrap().push_str(" World");

    assert_eq!(ext.get::<String>().unwrap(), "Hello World");

#### `pub fn remove<T: Send + Sync + 'static>(&mut self) -> Option<T>` [src]

Remove a type from this `Extensions`.

If a extension of this type existed, it will be returned.

# Example

    let mut ext = Extensions::new();
    ext.insert(5i32);
    assert_eq!(ext.remove::<i32>(), Some(5i32));
    assert!(ext.get::<i32>().is_none());

#### `pub fn clear(&mut self)` [src]

Clear the `Extensions` of all inserted extensions.

# Example

    let mut ext = Extensions::new();
    ext.insert(5i32);
    ext.clear();

    assert!(ext.get::<i32>().is_none());

## Trait Implementations

### `impl Debug for Extensions` [src]

#### `fn fmt(&self, f: &mut Formatter<'_>) -> Result` [src]

Formats the value using the given formatter. Read more

### `impl Default for Extensions` [src]

#### `fn default() -> Extensions` [src]

Returns the “default value” for a type. Read more

## Auto Trait Implementations

### `impl !RefUnwindSafe for Extensions`

### `impl Send for Extensions`

### `impl Sync for Extensions`

### `impl Unpin for Extensions`

### `impl !UnwindSafe for Extensions`

## Blanket Implementations

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `pub fn type_id(&self) -> TypeId` [src]

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

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow(&self) -> &T` [src]

Immutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow_mut(&mut self) -> &mut T` [src]

Mutably borrows from an owned value. Read more

### `impl<T> From<T> for T` [src]

#### `pub fn from(t: T) -> T` [src]

Performs the conversion.

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `pub fn into(self) -> U` [src]

Performs the conversion.

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>` [src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

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

The type returned in the event of a conversion error.

#### `pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>` [src]

Performs the conversion.