Introduce promise and async-await on emacs

00sync.el

(defun mstk-start-sync ()
  (call-process "sh" nil nil nil "-c" "sleep 3; echo OK")
  (message-box "mstk-start-sync finished."))

(mstk-start-sync)

01start-process.el

(defun mstk-start-async-1a ()
  (setq proc (start-process
              "mstk-start-async-1a"
              (generate-new-buffer " *sh*")
              "sh" "-c" "sleep 3; echo OK"))
  (set-process-sentinel proc 'mstk-async-sentinel-1a))

(defun mstk-async-sentinel-1a (_process _event)
  (message-box "mstk-start-async-1a finished."))

(mstk-start-async-1a)

02start-process.el

(defun mstk-start-async-1b ()
  (setq proc (start-process
              "mstk-start-async-1b"
              (generate-new-buffer " *sh*")
              "sh" "-c" "sleep 3; echo OK"))
  (set-process-sentinel proc (lambda (_process _event)
                               (message-box "mstk-start-async-1b finished."))))

(mstk-start-async-1b)

03make-process.el

(defun mstk-start-async-2a ()
  (make-process :name "mstk-start-async-2a"
                :buffer (generate-new-buffer " *sh*")
                :command '("sh" "-c" "sleep 3; echo OK")
                :sentinel 'mstk-async-sentinel-2a))

(defun mstk-async-sentinel-2a (process _event)
  (message-box "mstk-start-async-2a finished."))

(mstk-start-async-2a)

04make-process.el

(defun mstk-start-async-2b ()
  (make-process :name "mstk-start-async-2b"
                :buffer (generate-new-buffer " *sh*")
                :command '("sh" "-c" "sleep 3; echo OK")
                :sentinel (lambda (_process _event)
                            (message-box "mstk-start-async-2b finished."))))

(mstk-start-async-2b)

05promise.el

(require 'promise)

(defun mstk-start-promise-1a ()
  (promise-chain
      (promise:make-process "sh" "-c" "sleep 3; echo OK")
    (then
     (lambda (reason)
       (message-box "then %s" reason)))))

(mstk-start-promise-1a)

06promise.el

(require 'promise)

(defun mstk-start-promise-2a ()
  (promise-chain
      (promise:make-process "sh" "-c" "sleep 3; echo OK")
    (then
     (lambda (reason)
       (/ 1 0) ;; an error occurs!!
       (message-box "then %s" reason)))
    (promise-catch
     (lambda (reason)
       (message-box "catch error!! %s" reason)))
    (done
     (lambda (reason)
       (message-box "done. %s" reason)))))

(mstk-start-promise-2a)

07async-await.el

(require 'async-await)

(setq lexical-binding t)

(async-defun mstk-start-async-await-1a ()
  (await (promise:make-process "sh" "-c" "sleep 3; echo OK"))
  (message-box "finish"))

(mstk-start-async-await-1a)

08async-await.el

(require 'async-await)

(setq lexical-binding t)

(async-defun mstk-start-async-await-2a ()
  (condition-case reason
      (progn
        (await (promise:make-process "sh" "-c" "sleep 3; echo OK"))
        (/ 1 0) ;; an error occurs!!
        (message-box "finish"))
    (error (message-box "catch error!! %s" reason))))

(mstk-start-async-await-2a)