missionary.core/mbx

Usage

• (mbx) - define a new mailbox.
• m - used as a task, dequeue a message from mailbox m.
• (m x) - enqueue message x to mailbox m, return nil.

Description

A port constructor defining an unbounded, non-blocking FIFO mailbox. A mailbox is initially empty, then messages can be enqueued synchronously. Dequeuing is an asynchronous effect completing with the oldest message when the mailbox has some.

Examples

(require '[missionary.core :as m])

(def m (m/mbx))

(def main (m/sp (prn :> (m/? m) (m/? m) (m/? m))))

(def ps (main #(prn :success %) #(prn :failure %)))
(m :foo)
(m :bar)
(m :baz)
:> :foo :bar :baz
:success nil

Synchronicity

• mailbox definition is a synchronous effect.
• mailbox enqueuing is a synchronous effect.
• when the mailbox is empty, dequeuing completion is synchronous with enqueuing.
• when the mailbox is not empty, dequeuing completion is synchronous with dequeuing spawn.