Struct core::option::NoneError

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pub struct NoneError;

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

[−] Expand description

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

impl PartialEq<NoneError> for NoneError[+]

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fn eq(&self, other: &NoneError) -> bool[−]

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

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#[must_use]

fn ne(&self, other: &Rhs) -> bool[−]

This method tests for !=.

impl Eq for NoneError

impl Ord for NoneError[+]

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fn cmp(&self, other: &NoneError) -> Ordering[−]

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self where
    Self: Sized, [−]

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self where
    Self: Sized, [−]

Compares and returns the minimum of two values.

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

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

Restrict a value to a certain interval.

impl PartialOrd<NoneError> for NoneError[+]

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

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

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#[must_use]

fn lt(&self, other: &Rhs) -> bool[−]

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

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#[must_use]

fn le(&self, other: &Rhs) -> bool[−]

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

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#[must_use]

fn gt(&self, other: &Rhs) -> bool[−]

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

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#[must_use]

fn ge(&self, other: &Rhs) -> bool[−]

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

impl Clone for NoneError[+]

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fn clone(&self) -> NoneError[−]

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)[−]

Performs copy-assignment from source.

impl Hash for NoneError[+]

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

Feeds this value into the given [Hasher].

fn hash_slice<H: Hasher>(data: &[Self], state: &mut H) where
    Self: Sized, [−]

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

impl Debug for NoneError[+]

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

Formats the value using the given formatter.