325 - example program using channels

1 files changed, 48 insertions, 0 deletions

diff --git a/channel.mu b/channel.mu
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index 00000000..c56e8889
--- /dev/null
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+(def producer [
+  ; produce numbers 1 to 5 on a channel
+  ((default-scope scope-address) <- new (scope literal) (30 literal))
+  ((chan channel-address) <- arg)
+  ; n = 0
+  ((n integer) <- copy (0 literal))
+  { begin
+    ((done? boolean) <- lt (n integer) (5 literal))
+    (break-unless (done? boolean))
+    ; other threads might get between these prints
+    (print-primitive ("produce: " literal))
+    (print-primitive (n integer))
+    (print-primitive ("\n" literal))
+    ; 'box' n into a dynamically typed 'tagged value' because that's what
+    ; channels take
+    ((n2 integer-address) <- new (integer literal))
+    ((n2 integer-address deref) <- copy (n integer))
+    ((n3 tagged-value-address) <- new-tagged-value (integer-address literal) (n2 integer-address))
+    ((chan channel-address deref) <- write (chan channel-address) (n3 tagged-value-address deref))
+    ((n integer) <- add (n integer) (1 literal))
+    (continue)
+  }
+])
+
+(def consumer [
+  ; consume and print integers from a channel
+  ((default-scope scope-address) <- new (scope literal) (30 literal))
+  ((chan channel-address) <- arg)
+  { begin
+    ; read a tagged value from the channel
+    ((x tagged-value) (chan channel-address deref) <- read (chan channel-address))
+    ; unbox the tagged value into an integer
+    ((n2 integer-address) <- maybe-coerce (x tagged-value) (integer-address literal))
+    ; other threads might get between these prints
+    (print-primitive ("consume: " literal))
+    (print-primitive (n2 integer-address deref))
+    (print-primitive ("\n" literal))
+    (continue)
+  }
+])
+
+(def main [
+  ((chan channel-address) <- new-channel (3 literal))
+  ; create two background 'routines' that communicate by a channel
+  (fork (consumer fn) (chan channel-address))
+  (fork (producer fn) (chan channel-address))
+  (sleep (2000 literal))  ; wait for forked routines to effect the transfer
+])