Struct takeable::Takeable

pub struct Takeable<T> { /* fields omitted */ }

A wrapper-type that always holds a single T value.

This type is implemented using an Option<T>, however outside of the borrow_result function, this Option will always contain a value.

Panics

If the closure given to borrow or borrow_result panics, then the Takeable is left in an unusable state without holding a T. Calling any method on the object besides is_usable when in this state will result in a panic. This includes trying to dereference the object.

It is still safe to drop the value.

Methods

impl<T> Takeable<T>

fn new(value: T) -> Takeable<T>

Constructs a new Takeable<T> value.

fn as_ref(&self) -> &T

Gets a reference to the inner value.

fn as_mut(&mut self) -> &mut T

Gets a mutable reference to the inner value.

fn into_inner(self) -> T

Takes ownership of the inner value.

fn borrow<F>(&mut self, f: F) where
    F: FnOnce(T) -> T, 

Updates the inner value using the provided closure.

fn borrow_result<F, R>(&mut self, f: F) -> R where
    F: FnOnce(T) -> (T, R), 

Updates the inner value using the provided closure while also returns a result.

fn is_usable(&self) -> bool

Check if the object is still usable.

The object will always start out as usable, and can only enter an unusable state if the methods borrow or borrow_result are called with closures that panic.

Trait Implementations

impl<T: Clone> Clone for Takeable<T>

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

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Copy> Copy for Takeable<T>

impl<T: Debug> Debug for Takeable<T>

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<T: Eq> Eq for Takeable<T>

impl<T: PartialEq> PartialEq for Takeable<T>

fn eq(&self, __arg_0: &Takeable<T>) -> bool

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

fn ne(&self, __arg_0: &Takeable<T>) -> bool

This method tests for !=.

impl<T: Ord> Ord for Takeable<T>

fn cmp(&self, __arg_0: &Takeable<T>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

🔬 This is a nightly-only experimental API. (ord_max_min)

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

🔬 This is a nightly-only experimental API. (ord_max_min)

Compares and returns the minimum of two values.

impl<T: PartialOrd> PartialOrd for Takeable<T>

fn partial_cmp(&self, __arg_0: &Takeable<T>) -> Option<Ordering>

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

fn lt(&self, __arg_0: &Takeable<T>) -> bool

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

fn le(&self, __arg_0: &Takeable<T>) -> bool

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

fn gt(&self, __arg_0: &Takeable<T>) -> bool

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

fn ge(&self, __arg_0: &Takeable<T>) -> bool

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

impl<T: Hash> Hash for Takeable<T>

fn hash<__HT: Hasher>(&self, __arg_0: &mut __HT)

Feeds this value into the given [Hasher].

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

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

impl<T: Default> Default for Takeable<T>

fn default() -> Takeable<T>

Returns the "default value" for a type.

impl<T> Deref for Takeable<T>

type Target = T

The resulting type after dereferencing

fn deref(&self) -> &T

The method called to dereference a value

impl<T> DerefMut for Takeable<T>

fn deref_mut(&mut self) -> &mut T

The method called to mutably dereference a value