scripting: channel: Add channel-get! and channel-put! procedures.

* chickadee/scripting/channel.scm (channel-get!, channel-put!): New
  procedures.
* doc/api.texi [Channels]: Add docs.

1 files changed, 18 insertions, 4 deletions

diff --git a/chickadee/scripting/channel.scm b/chickadee/scripting/channel.scm
index 4d8583f..7ec11ce 100644
--- a/chickadee/scripting/channel.scm
+++ b/chickadee/scripting/channel.scm
@@ -23,7 +23,9 @@
   #:use-module (chickadee scripting script)
   #:export (make-channel
             channel?
+            channel-get!
             channel-get
+            channel-put!
             channel-put))
 
 ;; A very simplified notion of channels compared to guile-fibers.  In
@@ -55,18 +57,30 @@
              (get-cont data)
              (put-cont)))))))
 
+(define (channel-get! channel proc)
+  "Asynchronously retrieve a value from CHANNEL and call PROC with
+that value."
+  (enqueue! (channel-get-queue channel) proc)
+  (maybe-deliver channel))
+
 (define (channel-get channel)
   "Retrieve a value from CHANNEL.  The current script suspends until a
 value is available."
   (yield
    (lambda (cont)
-     (enqueue! (channel-get-queue channel) cont)
-     (maybe-deliver channel))))
+     (channel-get! channel cont))))
+
+(define noop (lambda () #t))
+
+(define* (channel-put! channel data #:optional (thunk noop))
+  "Asynchronously send DATA to CHANNEL and call THUNK after it has
+been received."
+  (enqueue! (channel-put-queue channel) (cons data thunk))
+  (maybe-deliver channel))
 
 (define (channel-put channel data)
   "Send DATA to CHANNEL.  The current script suspends until another
 script is available to retrieve the value."
   (yield
    (lambda (cont)
-     (enqueue! (channel-put-queue channel) (cons data cont))
-     (maybe-deliver channel))))
+     (channel-put! channel data cont))))