Struct ScopeStack 

pub struct ScopeStack { /* private fields */ }

Mutable stack of active scopes plus their scope-local registries.

The stack always contains an implicit root scope. Additional scopes are pushed as the public API opens lifecycle spans and removed when those spans close.

Implementations

impl ScopeStack

pub fn new() -> Self

Create a new scope stack containing only the implicit root scope.

Returns

A ScopeStack initialized with a single root scope and no scope-local registries.

pub fn push(&mut self, handle: ScopeHandle)

Push a scope handle onto the top of the stack.

Parameters

• handle: Scope handle to make the new top-most active scope.

pub fn top(&self) -> &ScopeHandle

Return the current top-most scope handle.

Returns

A shared reference to the active scope at the top of the stack.

Notes

This function never returns None because the implicit root scope is always present.

pub fn top_mut(&mut self) -> &mut ScopeHandle

Return the current top-most scope handle mutably.

Returns

A mutable reference to the active scope at the top of the stack.

pub fn root_uuid(&self) -> Uuid

Return the UUID of the implicit root scope.

Returns

The stable UUID of the root scope stored at the bottom of the stack.

pub fn scopes(&self) -> &[ScopeHandle]

Return the full ordered stack of scope handles.

Returns

A slice of scopes ordered from root to the current top-most scope.

pub fn find(&self, uuid: &Uuid) -> Option<&ScopeHandle>

Find a scope handle by UUID.

Parameters

• uuid: UUID of the scope to search for.

Returns

Some(&ScopeHandle) when the scope is active on this stack and None otherwise.

pub fn remove(&mut self, uuid: &Uuid) -> Result<ScopeHandle>

Remove the current top scope if it matches uuid.

Parameters

• uuid: UUID of the scope expected to be at the top of the stack.

Returns

A Result containing the removed ScopeHandle.

Errors

Returns FlowError::InvalidArgument when the scope exists but is not the current top of the stack or when the caller attempts to remove the implicit root scope. Returns FlowError::NotFound when the UUID is not present on the stack.

pub fn local_registries_mut( &mut self, uuid: &Uuid, ) -> Option<&mut ScopeLocalRegistries>

Get or create the scope-local registries for an active scope.

Parameters

• uuid: UUID of an active scope on this stack.

Returns

Some(&mut ScopeLocalRegistries) when the scope is active and None otherwise.

Notes

When the scope is active but has no registries yet, this function creates an empty scope-local registry set first.

pub fn collect_scope_local_registries<'a, T>( &'a self, field: impl Fn(&'a ScopeLocalRegistries) -> &'a SortedRegistry<T>, ) -> Vec<&'a SortedRegistry<T>>

Collect one registry field from every active scope that owns it.

Parameters

• field: Projection function selecting the registry field to collect from each scope-local registry.

Returns

A vector of registry references ordered from root toward the current top-most scope.

pub fn collect_scope_local_subscribers(&self) -> Vec<EventSubscriberFn>

Collect all scope-local subscribers visible from the active stack.

Returns

A vector of subscribers collected from each active scope that owns scope-local registries.

pub fn scope_registries_get(&self, uuid: &Uuid) -> Option<&ScopeLocalRegistries>

Return the scope-local registries for uuid without creating them.

Parameters

• uuid: UUID of the scope whose registries should be borrowed.

Returns

Some(&ScopeLocalRegistries) when registries already exist for that scope and None otherwise.

Trait Implementations

impl Debug for ScopeStack

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

Formats the value using the given formatter.

impl Default for ScopeStack

fn default() -> Self

Returns the “default value” for a type.