Rendezvous: Difference between revisions

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 Like in the rendezvous mechanism, parameters are not marshalled. This is because sharing immutable data between threads is safe.
 In contrast to ADA, the parameters are buffered until the printer becomes ready. But with a synchronous communication mechanism, this should not cause problems.
+=={{header|Perl 6}}==
+Perl 6 has no built-in support for rendezvous. I tried to simulate it using message passing and a lock - not sure if that counts.
+{{works with|Rakudo|2016.08}}
+<lang perl6>class X::OutOfInk is Exception {
+    method message() { "Printer out of ink" }
+}
+class Printer {
+    has Str      $.id;
+    has Int      $.ink = 5;
+    has Lock     $!lock .= new;
+    has ::?CLASS $.fallback;
+    method print ($line) {
+        $!lock.protect: {
+            if    $!ink      { say "$!id: $line"; $!ink-- }
+            elsif $!fallback { $!fallback.print: $line }
+            else             { die X::OutOfInk.new }
+        }
+    }
+}
+my $printer =
+    Printer.new: id => 'main', fallback =>
+    Printer.new: id => 'reserve';
+sub client ($id, @lines) {
+    start {
+        for @lines {
+            $printer.print: $_;
+            CATCH {
+                when X::OutOfInk { note "<$id stops for lack of ink>"; exit }
+            }
+        }
+        note "<$id is done>";
+    }
+}
+await
+    client('Humpty', q:to/END/.lines),
+        Humpty Dumpty sat on a wall.
+        Humpty Dumpty had a great fall.
+        All the king's horses and all the king's men,
+        Couldn't put Humpty together again.
+        END
+    client('Goose', q:to/END/.lines);
+        Old Mother Goose,
+        When she wanted to wander,
+        Would ride through the air,
+        On a very fine gander.
+        Jack's mother came in,
+        And caught the goose soon,
+        And mounting its back,
+        Flew up to the moon.
+        END</lang>
+{{out}}
+<pre>
+main: Humpty Dumpty sat on a wall.
+main: Old Mother Goose,
+main: Humpty Dumpty had a great fall.
+main: When she wanted to wander,
+main: All the king's horses and all the king's men,
+reserve: Would ride through the air,
+reserve: Couldn't put Humpty together again.
+reserve: On a very fine gander.
+<Humpty is done>
+reserve: Jack's mother came in,
+reserve: And caught the goose soon,
+<Goose stops for lack of ink>
+</pre>
 =={{header|PicoLisp}}==