Swift Task Cancellation Scope and Propagation

Swift Task Cancellation Propagation Scope

0 reputation · 22 Aug 2024, 20:57 UTC

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Swift Concurrency Model

The current Swift concurrency primitives, such as Task and AsyncStream, operate on a cooperative cancellation model.

Unresolved Boundary Behavior

There is no documented, built-in mechanism to automatically propagate cancellation from a parent task to its child tasks.

What is the expected scope of cancellation propagation within existing structured concurrency boundaries without explicit manual token handling? Does the Swift language specification define a concrete API for scoping cancellation, or is manual propagation always required for safety?

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