copy some async stuff from flan-utils

README

@@ -1,12 +1,15 @@
-Go-like channels for atomically passing information between threads.
+=== Go-like channels for atomically passing information between threads, and some other stuff. ===
 
 (channel:make-channel) ; make new channel
 (channel:make-channel 2) ; make new channel with max size of 2 (untested)
 
 (channel:-> chan item) ; send item to channel
-(channel:<- chan) ; receive from channel (values item is-not-closed)
+(channel:<- chan) ; receive from channel (values item is-not-closed), blocks until there is one
 (channel:release chan) ; close channel
 (channel:closed chan) ; is channel closed
+(channel:¬closed chan) ; (not (closed chan))
+
+--- Signalling ---
 
 (dispatcher:make-dispatcher) ; make dispatcher
 
@@ -14,6 +17,7 @@ Go-like channels for atomically passing information between threads.
 (dispatcher:sig name (optional value)) ; signal name in parallel
 (dispatcher:sig-serial name (optional value)) ; signal name in serial
 
+--- Atomic operations ---
 
 (box:make &optional value) ; make a box with default value
 

async-tools.lisp

@@ -0,0 +1,82 @@
+
+(in-package #:async-tools)
+
+(defun val (v) v)
+
+(defun sexpr-reader (stream char &key (func 'val))
+  "Read next token only if S expression, else return as is"
+  (if (char= (peek-char t stream t nil t) #\()
+    (values (funcall func (read stream t nil t)) t)
+    (let ((*readtable* (copy-readtable)))
+      (set-macro-character char nil)
+      (values (read-from-string (concatenate 'string (string char) (write-to-string (read stream t nil t)))) nil))))
+
+(defun async-reader (stream char)
+  (multiple-value-bind (thing okay) (sexpr-reader stream char)
+    (if okay
+      (cons 'async (list thing))
+      thing)))
+
+(defstruct promise
+  thread
+  value
+  ended)
+
+(defmacro async (&body form)
+  "Run body in seperate thread, returns promise."
+  `(let ((end (make-promise)))
+     (setf (promise-value end) nil)
+     (setf (promise-ended end) nil)
+     (setf (promise-thread end)
+	   (bt:make-thread
+	     #'(lambda ()
+		 (setf (promise-value end) (progn ,@form))
+		 (setf (promise-ended end) t))))
+     end))
+
+(defun wait (promise)
+  "Wait for promise to complete, returns the last value evaluated and T if the thread exited cleanly"
+  (bt:join-thread (promise-thread promise))
+  (value promise))
+
+(defun alive? (promise)
+  "Is the thread alive?"
+  (bt:thread-alive-p (promise-thread promise)))
+
+(defun value (promise)
+  "The current value of the promise and T if the thread exited cleanly, (returns nil nil if it has not terminated yet)"
+  (values (promise-value promise) (clean? promise)))
+
+(defun ended? (promise)
+  "Has the promise completed?"
+  (promise-ended promise))
+
+(defun thread (promise)
+  "The thread for the promise"
+  (promise-thread promise))
+
+(defun clean? (promise)
+  "Did the thread exit, and did it do so cleanly?"
+  (and (ended? promise) (not (alive? promise))))
+
+(defun kill (promise)
+  "Kill thread. Unclean exit."
+  (bt:destroy-thread (promise-thread promise)))
+
+(mapc 'export '(
+	promise
+	promise-p
+	wait
+	alive?
+	thread
+	value
+	ended?
+	clean?
+	async))
+
+(defmacro enable-reader ()
+  "Turn on reader macroi $(form) to run (async form)"
+  '(eval-when (:compile-toplevel :load-toplevel :execute)
+     (set-macro-character #\$ 'async-reader)))
+
+(export 'enable-reader)

cl-channel.asd

@@ -8,6 +8,7 @@
   :serial t
   :depends-on ( :bt-semaphore )
   :components ((:file "package")
+	       (:file "async-tools")
                (:file "cl-channel")
 	       (:file "cl-box")
 	       (:file "cl-dispatcher")))

cl-channel.lisp

@@ -7,6 +7,7 @@
   internal
   mutex)
 
+(async-tools:enable-reader)
 
 (mapc 'export (list
 (defun make-queue (&optional (from nil))
@@ -65,6 +66,9 @@
 (defun closed (chan) (%atomic chan
   (%channel-closed chan)))
 
+(defun ¬closed (chan)
+  (not (closed chan)))
+
 (defun poll (chan)
   (%atomic chan
 	   (queue-poll (%channel-internal chan))))
@@ -114,19 +118,19 @@
 
 ))
 
-#|(defun test ()
+(defun test ()
   (let ((chan (make-channel)))
-    $(progn
+     
-       (loop while ¬(closed chan) do (let ((val (<- chan)))
+       $(progn (loop while (not (closed chan)) do (let ((val (<- chan)))
 	 (pprint val)
 	 (pprint ".")
 	 (when (string-equal val "CLOSE")
 	   (release chan))))
        (print "Thread end")
        (print "."))
-     $(loop while ¬(closed chan) do
+     $(loop while (not (closed chan)) do
 	   (progn
 	     (sleep 2)
 	     (-> chan 'teste)))
-    (loop while ¬(closed chan) do (-> chan (write-to-string (read)))))
+    (loop while (not (closed chan)) do (-> chan (write-to-string (read)))))
-  (print "End"))|#
+  (print "End"))

cl-dispatcher.lisp

@@ -32,7 +32,7 @@
 	   (let ((hooks (assoc name (%dispatcher-hooks disp))))
 	     (if (null hooks)
 	       nil
-	       (mapcar #'(lambda (y) (bt:make-thread (funcall y x))) (cdr hooks))))))
+	       (mapcar #'(lambda (y) (bt:make-thread (lambda () (funcall y x)))) (cdr hooks))))))
 
 (defun sig-serial (disp name  &optional (x nil))
   (%atomic disp
@@ -40,13 +40,15 @@
 	     (if (null hooks)
 	       nil
 	       (mapc #'(lambda (y) (funcall y x)) (cdr hooks))))))
+
 ))
 
 (defun test ()
-  (let ((d (make)))
+  (let ((d (make-dispatcher)))
     (hook d "test" (lambda (x) (print x)))
     (hook d "test" (lambda (x) (print (cons "!!" x))))
     (hook d "test" (lambda (x) (print "HELLO")))
     
     (sig-serial d "test" 'uwu)
     (print 'signalled)))
+

package.lisp

@@ -1,5 +1,8 @@
 ;;;; package.lisp
 
+(defpackage #:async-tools
+  (:use #:cl))
+
 (defpackage #:cl-channel
   (:use #:cl)
   (:nicknames :channel))