core::option::NoneError - Rust
Description: API documentation for the Rust `NoneError` struct in crate `core`.
Keywords: rust, rustlang, rust-lang, NoneError

# [−][src]Struct core::option::NoneError

    pub struct NoneError;

🔬 This is a nightly-only experimental API. (`try_trait` #42327)

The error type that results from applying the try operator (`?`) to a `None` value. If you wish to allow `x?` (where `x` is an `Option<T>`) to be converted into your error type, you can implement `impl From<NoneError>` for `YourErrorType`. In that case, `x?` within a function that returns `Result<_, YourErrorType>` will translate a `None` value into an `Err` result.

## Trait Implementations

### `impl Copy for NoneError`[src]

### `impl PartialEq<NoneError> for NoneError`[src]

#### `fn eq(&self, other: &NoneError) -> bool`[src]

This method tests for `self` and `other` values to be equal, and is used by `==`. Read more

#### `
#[must_use]
fn ne(&self, other: &Rhs) -> bool`
1.0.0
[src]

This method tests for `!=`.

### `impl Eq for NoneError`[src]

### `impl Ord for NoneError`[src]

#### `fn cmp(&self, other: &NoneError) -> Ordering`[src]

This method returns an `Ordering` between `self` and `other`. Read more

#### `fn max(self, other: Self) -> Self where
Self: Sized,`
1.21.0
[src]

Compares and returns the maximum of two values. Read more

#### `fn min(self, other: Self) -> Self where
Self: Sized,`
1.21.0
[src]

Compares and returns the minimum of two values. Read more

#### `fn clamp(self, min: Self, max: Self) -> Self where
Self: Sized,` [src]

🔬 This is a nightly-only experimental API. (`clamp` #44095)

Restrict a value to a certain interval. Read more

### `impl PartialOrd<NoneError> for NoneError`[src]

#### `fn partial_cmp(&self, other: &NoneError) -> Option<Ordering>`[src]

This method returns an ordering between `self` and `other` values if one exists. Read more

#### `
#[must_use]
fn lt(&self, other: &Rhs) -> bool`
1.0.0
[src]

This method tests less than (for `self` and `other`) and is used by the `<` operator. Read more

#### `
#[must_use]
fn le(&self, other: &Rhs) -> bool`
1.0.0
[src]

This method tests less than or equal to (for `self` and `other`) and is used by the `<=` operator. Read more

#### `
#[must_use]
fn gt(&self, other: &Rhs) -> bool`
1.0.0
[src]

This method tests greater than (for `self` and `other`) and is used by the `>` operator. Read more

#### `
#[must_use]
fn ge(&self, other: &Rhs) -> bool`
1.0.0
[src]

This method tests greater than or equal to (for `self` and `other`) and is used by the `>=` operator. Read more

### `impl Clone for NoneError`[src]

#### `fn clone(&self) -> NoneError`[src]

Returns a copy of the value. Read more

#### `fn clone_from(&mut self, source: &Self)`
1.0.0
[src]

Performs copy-assignment from `source`. Read more

### `impl Hash for NoneError`[src]

#### `fn hash<__H: Hasher>(&self, state: &mut __H)`[src]

Feeds this value into the given [`Hasher`]. Read more

#### `fn hash_slice<H: Hasher>(data: &[Self], state: &mut H) where
Self: Sized,`
1.3.0
[src]

Feeds a slice of this type into the given [`Hasher`]. Read more

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

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

Formats the value using the given formatter. Read more

## Auto Trait Implementations

### `impl Send for NoneError`

### `impl Sync for NoneError`

## Blanket Implementations

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

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

Performs the conversion.

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

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

Performs the conversion.

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

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

The type returned in the event of a conversion error.

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

Performs the conversion.

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

#### `type Error = Infallible`

The type returned in the event of a conversion error.

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

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

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

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

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