# Struct std::collections::hash_map::OccupiedError[−][src]

    pub struct OccupiedError<'a, K: 'a, V: 'a> {
        pub entry: OccupiedEntry<'a, K, V>,
        pub value: V,
    }

🔬 This is a nightly-only experimental API. (`map_try_insert` #82766)

The error returned by `try_insert` when the key already exists.

Contains the occupied entry, and the value that was not inserted.

## Fields

`entry: OccupiedEntry<'a, K, V>`
🔬 This is a nightly-only experimental API. (`map_try_insert` #82766)

The entry in the map that was already occupied.

`value: V`
🔬 This is a nightly-only experimental API. (`map_try_insert` #82766)

The value which was not inserted, because the entry was already occupied.

## Trait Implementations

### `impl<K: Debug, V: Debug> Debug for OccupiedError<'_, K, V>`[src]

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

Formats the value using the given formatter. Read more

### `impl<'a, K: Debug, V: Debug> Display for OccupiedError<'a, K, V>`[src]

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

Formats the value using the given formatter. Read more

### `impl<'a, K: Debug, V: Debug> Error for OccupiedError<'a, K, V>`[src]

#### `fn description(&self) -> &str`[src]

👎 Deprecated since 1.42.0:

use the Display impl or to_string()

Read more

#### `fn source(&self) -> Option<&(dyn Error + 'static)>`1.30.0[src]

The lower-level source of this error, if any. Read more

#### `fn backtrace(&self) -> Option<&Backtrace>`[src]

🔬 This is a nightly-only experimental API. (`backtrace` #53487)

Returns a stack backtrace, if available, of where this error occurred. Read more

#### `fn cause(&self) -> Option<&dyn Error>`1.0.0[src]

👎 Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

## Auto Trait Implementations

### `impl<'a, K, V> RefUnwindSafe for OccupiedError<'a, K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, K, V> Send for OccupiedError<'a, K, V> where
K: Send,
V: Send,`

### `impl<'a, K, V> Sync for OccupiedError<'a, K, V> where
K: Sync,
V: Sync,`

### `impl<'a, K, V> Unpin for OccupiedError<'a, K, V> where
K: Unpin,
V: Unpin,`

### `impl<'a, K, V> !UnwindSafe for OccupiedError<'a, K, V>`

## 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ⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Future + Unpin + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[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ⓘ

### Notable traits for &'_ mut I

`impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<'_, F> Future for &'_ mut F where
F: Future + Unpin + ?Sized, type Output = <F as Future>::Output;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[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> ToString for T where
T: Display + ?Sized,` [src]

#### `pub default fn to_string(&self) -> String`[src]

Converts the given value to a `String`. Read more

### `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.