Sync

Task/Synchronous-concurrency/D/synchronous-concurrency.d

@@ -1,32 +1,20 @@
-import tools.threads, std.stdio, std.stream, std.thread;
+import std.algorithm, std.concurrency, std.stdio;
 
 void main() {
-  // line or EOF
-  struct InputLine {
-    string data;
-    bool eof;
-    static InputLine opCall(string s) { InputLine res; res.data = s; return res; }
-    static InputLine EOF() { InputLine res; res.eof = true; return res; }
-  }
-  auto LineCh = new MessageChannel!(InputLine),
-    ResultCh = new MessageChannel!(int);
-  auto printer = new Thread({
-    int count;
-    while (true) {
-      auto line = LineCh.get();
-      if (line.eof) break;
-      count ++;
-      writefln(count, ": ", line.data);
-    }
-    ResultCh.put(count);
-    return 0;
-  });
-  printer.start;
-  auto file = new File("input.txt");
-  while (!file.eof()) {
-    auto line = file.readLine();
-    LineCh.put(InputLine(line));
-  }
-  LineCh.put(InputLine.EOF());
-  writefln("Count: ", ResultCh.get());
+    auto printer = spawn(&printTask, thisTid);
+    auto f = File("input.txt","r");
+    foreach (string line; lines(f))
+        send(printer, line);
+    send(printer, true);    //EOF
+    auto n = receiveOnly!(int)();
+    stdout.writefln("\n%d lines printed.", n);
+}
+
+void printTask(Tid reader) {
+    int n = 0;
+    for (bool eof = false; !eof;)
+        receive(
+            (string line) {stdout.write(line); n++;},
+            (bool) {send(reader, n); eof = true;}
+        );
 }