axiom-assume-isolated

Apply assumeIsolated patterns to synchronously access actor-isolated state when the current isolation domain is guaranteed correct. This avoids asynchronous hops and prevents race conditions by crashing immediately if the context is misaligned.

MainActor.assumeIsolated crashes immediately if the synchronous execution context is misaligned with the actor's executor. It provides safe access to MainActor state when you confidently know the current isolation domain is correct.

Use custom actor assumeIsolated patterns when protocol callbacks or delegate methods are guaranteed to run on a specific custom actor. This allows synchronous state access without async hops while verifying executor alignment.

Use MainActor.assumeIsolated to synchronously access isolated state within your test context. It executes MainActor code synchronously without async hops, crashing safely if the test context is misaligned with the MainActor executor.

Yes, @preconcurrency shorthand patterns help apply assumeIsolated to legacy delegate callbacks. This allows synchronous access to actor-isolated state when delegate callbacks are guaranteed to run on the correct isolation domain.

The primary limitation of assumeIsolated is that it crashes the application if the execution context is misaligned with the actor's executor. It must only be used when the current isolation domain is confidently verified as correct.