dispatch_async versus Task.detached for offloading work
WHAT IT TESTS: GCD versus structured concurrency. OUTLINE: dispatch_async submits a closure to a queue; Task.detached starts an unstructured async task off the current actor without inheriting context.
WHAT IT TESTS: knowing when to use GCD versus Swift Concurrency and the cost of detaching. ANSWER OUTLINE: dispatch_async enqueues a closure on a chosen dispatch queue, a thread-pool model with no async/await. Task.detached creates an unstructured Task that does not inherit the enclosing actor, priority, or task-local values, running off the main actor. Prefer plain Task or async functions that hop to the right executor; reach for detached only when you deliberately need to escape actor isolation.
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- #swift
- #concurrency
- #gcd
- #async-await
- #actors
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