Contents

assertIsolated(_:file:line:)

Stops program execution if the current task is not executing on this actor’s serial executor.

Declaration

@backDeployed(before: macOS 14.0, iOS 17.0, watchOS 10.0, tvOS 17.0)
static func assertIsolated(_ message: @autoclosure () -> String = String(), file: StaticString = #fileID, line: UInt = #line)

Parameters

  • message:

    The message to print if the assertion fails.

  • file:

    The file name to print if the assertion fails. The default is where this method was called.

  • line:

    The line number to print if the assertion fails The default is where this method was called.

Discussion

This function’s effect varies depending on the build flag used:

  • In playgrounds and -Onone builds (the default for Xcode’s Debug configuration), stops program execution in a debuggable state after printing message.

  • In -O builds (the default for Xcode’s Release configuration), the isolation check is not performed and there are no effects.