mirai (Stop)

Stops a 'mirai' if still in progress, causing it to resolve immediately to an 'errorValue' 20 (Operation canceled).

Usage

stop_mirai(x)

Arguments

x

(mirai | list) a 'mirai' object or list of 'mirai' objects.

Value

Logical TRUE if the cancellation request was successful (was awaiting execution or in execution), or else FALSE (if already completed or previously cancelled). Will always return FALSE if not using dispatcher.

Or a vector of logical values if supplying a list of 'mirai', such as those returned by mirai_map().

Details

Cancellation requires dispatcher. If the 'mirai' is awaiting execution, it is discarded from the queue and never evaluated. If already executing, an interrupt is sent.

A cancellation request does not guarantee the task stops: it may have already completed before the interrupt is received, and compiled code is not always interruptible. Take care if the code performs side effects such as writing to files.

Examples

if (FALSE) { # interactive()
m <- mirai(Sys.sleep(n), n = 5)
stop_mirai(m)
m$data
}