Struct ExtensionPoint 

pub struct ExtensionPoint<T: ?Sized> { /* private fields */ }

Typed, name-indexed collection of Arc<T>.

Cheap to clone; clones share the same underlying entries.

Implementations

impl<T: ?Sized> ExtensionPoint<T>

pub fn new() -> Self

Construct an empty extension point.

pub fn len(&self) -> usize

Number of registered entries.

pub fn is_empty(&self) -> bool

Returns true if the extension point has no entries.

pub fn names(&self) -> Vec<String>

Returns a sorted list of registered names. Sorting makes the result stable for snapshot tests and log output.

pub fn snapshot(&self) -> Vec<(String, Arc<T>)>

Take a consistent snapshot of (name, Arc<T>) pairs.

impl<T: ?Sized + Send + Sync + 'static> ExtensionPoint<T>

pub fn register( &self, name: impl Into<String>, value: Arc<T>, ) -> Result<(), ExtensionError>

Register a new entry. Errors if the name is already in use.

Errors

• ExtensionError::AlreadyRegistered if the name is taken.
• ExtensionError::LockPoisoned if the internal lock was poisoned by a panic.

pub fn register_or_replace( &self, name: impl Into<String>, value: Arc<T>, ) -> Option<Arc<T>>

Register a new entry, replacing any existing one with the same name. Returns the previous Arc<T>, or None if there was none.

pub fn unregister(&self, name: &str) -> Result<Option<Arc<T>>, ExtensionError>

Remove an entry. Returns the removed Arc<T>, or None if the name was not present.

Refuses to remove an entry whose strong count is greater than one (i.e. external callers still hold a reference).

pub fn replace(&self, name: &str, new: Arc<T>) -> Result<Arc<T>, ExtensionError>

Atomically replace an entry. Returns the previous Arc<T>, or ExtensionError::NotFound if the name was not present.

After this call, new ExtensionPoint::get calls return new. Callers that already hold the old Arc<T> continue to operate on the old instance until they drop it.

Errors

• ExtensionError::NotFound if the name was not present.

pub fn get(&self, name: &str) -> Option<Arc<T>>

Look up an entry by name.

pub fn get_required(&self, name: &str) -> Result<Arc<T>, ExtensionError>

Look up an entry by name, returning ExtensionError::NotFound if missing.

pub fn contains(&self, name: &str) -> bool

Returns true if the given name is registered.

Trait Implementations

impl<T: ?Sized> Clone for ExtensionPoint<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: ?Sized> Default for ExtensionPoint<T>

fn default() -> Self

Returns the “default value” for a type.