Asynchronous task multiplexing and chaining

A system comprising:

• a requesting entity, the requesting entity including a first task chain having a shared async task that is shared with a second task chain, including to provide results of successfully running the shared async task to a listener of the first task chain and to a listener of the second task chain;
• and
• a multiplexer that maintains an association of identity information of the listener of the first task chain with the async task and identity information of the listener of the second task chain with the async task, the multiplexer configured to notify the listener of the first task chain and the listener of the second task chain when the async task completes, and the multiplexer further configured to prevent cancellation of the listener of the second task chain from cancelling the async task if the listener of the first task chain has not cancelled, and to prevent cancellation of the listener of the first task chain from cancelling the async task if the listener of the second task chain has not cancelled.

One or more machine-readable storage media having machine-executable instructions, which when executed perform steps, comprising:

• maintaining an identity of a first listener and an identity of a second listener in a listener set of one or more listeners associated with a shared async task;
• receiving a cancel request corresponding to cancellation of the second listener, and based upon the cancel request, removing the identity of the second listener from the set of listeners associated with the shared async task;
• determining whether at least one listener remains in the listener set, and if so, running the shared async task, and notifying each listener in the set of listeners upon completion of the async task.