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# Module scope_stack

> Scope stack storage and propagation helpers.

Generated from `cargo doc --no-deps -p nemo-relay -p nemo-relay-adaptive -p nemo-relay-pii-redaction -p nemo-relay-ffi -p nemo-relay-types -p nemo-relay-plugin -p nemo-relay-worker-proto -p nemo-relay-worker`.

Scope stack storage and propagation helpers.

The runtime tracks the current scope hierarchy through a shared [`ScopeStack`](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-scopestack) stored in task-local or thread-local state. Advanced callers can use this module to inspect the active scope chain or propagate scope context into worker threads.

## Structs

* [PropagationContext](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-propagationcontext): Versioned, transport-neutral causal context for crossing a Relay boundary.
* [ScopeStack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-scopestack): Mutable stack of active scopes plus their scope-local registries.
* [ScopeStackEntry](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-scopestackentry): Identity of one entry in the visible Relay scope stack.
* [ScopeStackSnapshot](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-scopestacksnapshot): Owned root-to-top values from one coherent read of a visible scope stack.
* [ThreadScopeStackBinding](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-threadscopestackbinding): Captured thread-local scope stack binding.

## Statics

* [TASK_SCOPE_STACK](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/static-task-scope-stack): Task-local scope stack handle used by async execution contexts.

## Functions

* [capture_propagation_context](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-propagation-context): Capture the current causal parent and its Relay root when available.
* [capture_propagation_context_with_root](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-propagation-context-with-root): Capture the current causal parent and an application-supplied session root. Without an imported W3C parent, the supplied root determines the receiver's trace. An imported W3C parent retains precedence over the Relay root. Passing `None` has the same behavior as [`capture_rootless_propagation_context`](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-rootless-propagation-context).
* [capture_rootless_propagation_context](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-rootless-propagation-context): Capture the current causal parent without a root UUID.
* [capture_thread_scope_stack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-thread-scope-stack): Capture the current thread-local scope stack binding.
* [capture_traceparent](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-traceparent): Capture the current canonical W3C `traceparent` value.
* [create_scope_stack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-create-scope-stack): Create a new scope stack handle with an implicit root scope.
* [create_scope_stack_from_propagation](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-create-scope-stack-from-propagation): Create an isolated scope stack rooted below a supplied propagation context.
* [current_scope_stack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-current-scope-stack): Return the scope stack visible to the current execution context.
* [current_scope_stack_snapshot](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-current-scope-stack-snapshot): Return detached identities from the calling context's explicitly active stack.
* [fork_scope_stack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-fork-scope-stack): Create an isolated scope stack below the current causal parent.
* [propagate_scope_to_thread](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-propagate-scope-to-thread): Capture the current scope stack handle for use in another thread.
* [restore_thread_scope_stack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-restore-thread-scope-stack): Restore a previously captured thread-local scope stack binding.
* [scope_stack_active](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-scope-stack-active): Report whether the current context has an explicitly active scope stack.
* [set_thread_scope_stack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-set-thread-scope-stack): Install an explicit scope stack for the current thread.
* [sync_thread_scope_stack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-sync-thread-scope-stack): Synchronize the thread-local scope stack without marking it explicit.
* [task_scope_push](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-task-scope-push): Push a scope handle onto the active stack.
* [task_scope_remove](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-task-scope-remove): Remove a scope handle from the active stack.
* [task_scope_top](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-task-scope-top): Clone the current top-most scope handle from the active stack.
* [with_active_event_uuid](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-with-active-event-uuid): Run a future with `uuid` as the causally active managed event.
* [with_scope_stack](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-with-scope-stack): Run a synchronous callback with `handle` as the visible scope stack.

## Type Aliases

* [ScopeStackHandle](/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/type-scopestackhandle): Shared handle type for the runtime scope stack.

> Scope stack storage and propagation helpers.

## Docs

- [Struct Propagation Context](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-propagationcontext.md): Versioned, transport-neutral causal context for crossing a Relay boundary.
- [Struct Scope Stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-scopestack.md): Mutable stack of active scopes plus their scope-local registries.
- [Struct Scope Stack Entry](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-scopestackentry.md): Identity of one entry in the visible Relay scope stack.
- [Struct Scope Stack Snapshot](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-scopestacksnapshot.md): Owned root-to-top values from one coherent read of a visible scope stack.
- [Struct Thread Scope Stack Binding](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/struct-threadscopestackbinding.md): Captured thread-local scope stack binding.
- [Static TASK_SCOPE_STACK](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/static-task-scope-stack.md): Task-local scope stack handle used by async execution contexts.
- [Function capture_propagation_context](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-propagation-context.md): Capture the current causal parent and its Relay root when available.
- [Function capture_propagation_context_with_root](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-propagation-context-with-root.md): Capture the current causal parent and an application-supplied session root. Without an imported W3C parent, the supplied root determines the receiver's trace. An imported W3C parent retains precedence over the Relay root. Passing `None` has the same behavior as `capture_rootless_propagation_context`.
- [Function capture_rootless_propagation_context](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-rootless-propagation-context.md): Capture the current causal parent without a root UUID.
- [Function capture_thread_scope_stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-thread-scope-stack.md): Capture the current thread-local scope stack binding.
- [Function capture_traceparent](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-capture-traceparent.md): Capture the current canonical W3C `traceparent` value.
- [Function create_scope_stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-create-scope-stack.md): Create a new scope stack handle with an implicit root scope.
- [Function create_scope_stack_from_propagation](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-create-scope-stack-from-propagation.md): Create an isolated scope stack rooted below a supplied propagation context.
- [Function current_scope_stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-current-scope-stack.md): Return the scope stack visible to the current execution context.
- [Function current_scope_stack_snapshot](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-current-scope-stack-snapshot.md): Return detached identities from the calling context's explicitly active stack.
- [Function fork_scope_stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-fork-scope-stack.md): Create an isolated scope stack below the current causal parent.
- [Function propagate_scope_to_thread](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-propagate-scope-to-thread.md): Capture the current scope stack handle for use in another thread.
- [Function restore_thread_scope_stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-restore-thread-scope-stack.md): Restore a previously captured thread-local scope stack binding.
- [Function scope_stack_active](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-scope-stack-active.md): Report whether the current context has an explicitly active scope stack.
- [Function set_thread_scope_stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-set-thread-scope-stack.md): Install an explicit scope stack for the current thread.
- [Function sync_thread_scope_stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-sync-thread-scope-stack.md): Synchronize the thread-local scope stack without marking it explicit.
- [Function task_scope_push](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-task-scope-push.md): Push a scope handle onto the active stack.
- [Function task_scope_remove](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-task-scope-remove.md): Remove a scope handle from the active stack.
- [Function task_scope_top](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-task-scope-top.md): Clone the current top-most scope handle from the active stack.
- [Function with_active_event_uuid](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-with-active-event-uuid.md): Run a future with `uuid` as the causally active managed event.
- [Function with_scope_stack](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/fn-with-scope-stack.md): Run a synchronous callback with `handle` as the visible scope stack.
- [Type Alias Scope Stack Handle](https://docs.nvidia.com/nemo/relay/v0.11.0/reference/api/rust-library-reference/nemo-relay/api/runtime/scope_stack/type-scopestackhandle.md): Shared handle type for the runtime scope stack.