Struct internment::Intern

pub struct Intern<T: 'static> { /* fields omitted */ }

Implementations

impl<T: Eq + Hash + Send + Sync + 'static> Intern<T>

pub fn new(val: T) -> Intern<T>

Intern a value. If this value has not previously been interned, then new will allocate a spot for the value on the heap. Otherwise, it will return a pointer to the object previously allocated.

Note that Intern::new is a bit slow, since it needs to check a HashSet protected by a Mutex.

pub fn from<'a, Q: ?Sized + Eq + Hash + 'a>(val: &'a Q) -> Intern<T> where
    T: Borrow<Q> + From<&'a Q>, 

Intern a value from a reference.

If this value has not previously been interned, then new will allocate a spot for the value on the heap and generate that value using T::from(val).

pub fn as_ref(self) -> &'static T

Get a long-lived reference to the data pointed to by an Intern, which is never freed from the intern pool.

pub fn num_objects_interned() -> usize

See how many objects have been interned. This may be helpful in analyzing memory use.

Trait Implementations

impl<T> AsRef<T> for Intern<T>

fn as_ref(&self) -> &T

Performs the conversion.

impl<T> Borrow<T> for Intern<T>

fn borrow(&self) -> &T

Immutably borrows from an owned value.

impl<T> Clone for Intern<T>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Intern<T>

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

Formats the value using the given formatter.

impl<T: Eq + Hash + Send + Sync + Default + 'static> Default for Intern<T>

fn default() -> Intern<T>

Returns the “default value” for a type.

impl<T> Deref for Intern<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<T: Display> Display for Intern<T>

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

Formats the value using the given formatter.

impl<T: Eq + Hash + Send + Sync + 'static> From<T> for Intern<T>

fn from(t: T) -> Self

Performs the conversion.

impl<T> Hash for Intern<T>

The hash implementation returns the hash of the pointer value, not the hash of the value pointed to. This should be irrelevant, since there is a unique pointer for every value, but it is observable, since you could compare the hash of the pointer with hash of the data itself.

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, 

Feeds a slice of this type into the given Hasher.

impl<T: Ord> Ord for Intern<T>

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

#[must_use]

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

Compares and returns the maximum of two values.

#[must_use]

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

Compares and returns the minimum of two values.

#[must_use]

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl<T> PartialEq<Intern<T>> for Intern<T>

fn eq(&self, other: &Intern<T>) -> bool

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

#[must_use]

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

This method tests for !=.

impl<T: PartialOrd> PartialOrd<Intern<T>> for Intern<T>

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

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

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

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

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

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

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

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

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

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

impl<T> Pointer for Intern<T>

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

Formats the value using the given formatter.

impl<T> Copy for Intern<T>

An Intern is Copy, which is unusal for a pointer. This is safe because we never free the data pointed to by an Intern.

impl<T> Eq for Intern<T>