Struct Opt

pub struct Opt<T> { /* private fields */ }

Implementations

impl<T> Opt<T>

pub fn none(value: T) -> Opt<T>

Construct an option with no value.

Note: perhaps unexpectedly, this function accepts a value argument. This is necessary given the underlying data structure.

pub fn some(value: T) -> Opt<T>

Construct an option with ‘some’ value.

impl<T> Opt<T>

pub fn is_none(&self) -> bool

pub fn is_some(&self) -> bool

pub fn set_none(&mut self)

pub fn set_some(&mut self)

pub fn set_some_value(&mut self, value: T)

pub fn as_ref(&self) -> Opt<&T>

Converts from &Opt<T> to Opt<&T>.

pub fn as_mut(&mut self) -> Opt<&mut T>

Converts from &mut Opt<T> to Opt<&mut T>.

pub fn expect(self, msg: &str) -> T

pub fn unwrap(self) -> T

pub fn unwrap_or(self, default: T) -> T

pub fn unwrap_or_else<F: FnOnce() -> T>(self, f: F) -> T

pub fn map<U, F: FnOnce(T) -> U>(self, f: F) -> Opt<U>

Applies the function f to the value; regardless if Opt<T> is empty or not. Does not modify the ‘emptiness’ of the option. (Note: This behavior, though consistent, may seem strange at first.)

pub fn map_in_place<F: FnOnce(&mut T)>(&mut self, f: F)

pub fn map_or<U, F: FnOnce(T) -> U>(self, default: U, f: F) -> U

pub fn map_or_else<U, D: FnOnce() -> U, F: FnOnce(T) -> U>( self, default: D, f: F, ) -> U

pub fn ok_or<E>(self, err: E) -> Result<T, E>

pub fn ok_or_else<E, F: FnOnce() -> E>(self, err: F) -> Result<T, E>

Trait Implementations

impl<T: Clone> Clone for Opt<T>

fn clone(&self) -> Opt<T>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug> Debug for Opt<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Hash> Hash for Opt<T>

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

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T: Ord> Ord for Opt<T>

fn cmp(&self, other: &Opt<T>) -> 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,

Restrict a value to a certain interval.

impl<T> PartialEq for Opt<T>

where T: PartialEq,

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T: PartialOrd> PartialOrd for Opt<T>

fn partial_cmp(&self, other: &Opt<T>) -> Option<Ordering>

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

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

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

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

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

impl<T: Copy> Copy for Opt<T>

impl<T: Eq> Eq for Opt<T>