Scope

A Scope owns finalizers for resources and child fibers. Closing it runs registered cleanup in reverse order, at most once, and waits for cleanup before returning.

Most application code should not construct or mutate Scope directly. Use the Flow-level operations:

• Flow.scoped creates and closes a child scope.
• Flow.scopeAcquireRelease acquires a value into the current scope.
• Flow.scopeResource acquires a reusable Resource description.
• Flow.scopeDisposable and Flow.scopeAsyncDisposable register existing .NET resources.
• Flow.scopeFinalizer registers custom cleanup as a release flow.
• Flow.forkResource acquires a Resource in a fiber and registers its release with the current scope.

A forked fiber has its own scope and releases its scoped resources when it settles. Flow.zipPar, Flow.sequencePar, and Flow.traversePar run their flows in one shared scope; Flow.race gives each branch its own scope, and each timed flow runs in its own scope. Whichever scope holds the value the caller receives stays open: it moves to the caller's scope and closes with it, so its resources live as if the caller had acquired them. Any other scope is released — a failed parallel group or a failed race winner closes before the combinator returns, a timed flow that fails or times out closes before the combinator returns (on timeout, before the fallback runs), and a race loser closes once it is interrupted, which may be after race returns.

This runtime lifetime differs from F# use and use!, which dispose when their lexical computation-expression body exits. A Flow scope can span functions, subflows, stream pulls, and child fibers.

Read the Scopes guide for a timeline of root, lexical, child, and nested lifetimes before using the low-level members listed below.

Scope transfer per combinator