Method Concurrent.fold()

Method fold

Future fold(array(Future) futures, mixed initial, function(mixed, mixed, __unknown__ ... :mixed) fun, mixed ... extra)

Description

Return a Future that represents the accumulated results of applying fun to the results of the futures in turn.

Parameter initial

Initial value of the accumulator.

Parameter fun

Function to apply. The first argument is the result of one of the futures, the second the current accumulated value, and any further from extra.

Note

If fun throws an error it will fail the Future.

Note

fun may be called in any order, and will be called once for every Future in futures, unless one of calls fails in which case no further calls will be performed.

Note

The returned Future does NOT have any state (eg backend) propagated from the futures. This must be done by hand.