New task API

doc/tutorial.md

@@ -2375,10 +2375,10 @@ module `task`.  Let's begin with the simplest one, `task::spawn()`:
 
 ~~~~
 let some_value = 22;
-let child_task = task::spawn {||
+task::spawn {||
     std::io::println("This executes in the child task.");
     std::io::println(#fmt("%d", some_value));
-};
+}
 ~~~~
 
 The argument to `task::spawn()` is a [unique
@@ -2456,70 +2456,66 @@ let result = comm::recv(port);
 ## Creating a task with a bi-directional communication path
 
 A very common thing to do is to spawn a child task where the parent
-and child both need to exchange messages with each other. The function
-`task::spawn_connected()` supports this pattern. We'll look briefly at
-how it is used.
+and child both need to exchange messages with each
+other. The function `task::spawn_listener()` supports this pattern. We'll look
+briefly at how it is used.
 
-To see how `spawn_connected()` works, we will create a child task
+To see how `spawn_listener()` works, we will create a child task
 which receives `uint` messages, converts them to a string, and sends
 the string in response.  The child terminates when `0` is received.
 Here is the function which implements the child task:
 
 ~~~~
-fn stringifier(from_par: comm::port<uint>,
-               to_par: comm::chan<str>) {
+fn stringifier(from_parent: comm::port<uint>,
+               to_parent: comm::chan<str>) {
     let value: uint;
     do {
-        value = comm::recv(from_par);
-        comm::send(to_par, uint::to_str(value, 10u));
+        value = comm::recv(from_parent);
+        comm::send(to_parent, uint::to_str(value, 10u));
     } while value != 0u;
 }
 
 ~~~~
+
 You can see that the function takes two parameters.  The first is a
 port used to receive messages from the parent, and the second is a
 channel used to send messages to the parent.  The body itself simply
 loops, reading from the `from_par` port and then sending its response
 to the `to_par` channel.  The actual response itself is simply the
 strified version of the received value, `uint::to_str(value)`.
-
+ 
 Here is the code for the parent task:
+
 ~~~~
-# fn stringifier(from_par: comm::port<uint>,
-#                to_par: comm::chan<str>) {
-#     comm::send(to_par, "22");
-#     comm::send(to_par, "23");
-#     comm::send(to_par, "0");
+# fn stringifier(from_parent: comm::port<uint>,
+#                to_parent: comm::chan<str>) {
+#     comm::send(to_parent, "22");
+#     comm::send(to_parent, "23");
+#     comm::send(to_parent, "0");
 # }
 fn main() {
-    let t = task::spawn_connected(stringifier);
-    comm::send(t.to_child, 22u);
-    assert comm::recv(t.from_child) == "22";
-    comm::send(t.to_child, 23u);
-    assert comm::recv(t.from_child) == "23";
-    comm::send(t.to_child, 0u);
-    assert comm::recv(t.from_child) == "0";
-}
-~~~~
-
-The call to `spawn_connected()` on the first line will instantiate the
-various ports and channels and startup the child task.  The returned
-value, `t`, is a record of type `task::connected_task<uint,str>`.  In
-addition to the task id of the child, this record defines two fields,
-`from_child` and `to_child`, which contain the port and channel
-respectively for communicating with the child.  Those fields are used
-here to send and receive three messages from the child task.
-
-## Joining a task
-
-The function `spawn_joinable()` is used to spawn a task that can later
-be joined. This is implemented by having the child task send a message
-when it has completed (either successfully or by failing). Therefore,
-`spawn_joinable()` returns a structure containing both the task ID and
-the port where this message will be sent---this structure type is
-called `task::joinable_task`. The structure can be passed to
-`task::join()`, which simply blocks on the port, waiting to receive
-the message from the child task.
+    let from_child = comm::port();
+    let to_parent = comm::chan(from_child);
+    let to_child = task::spawn_listener {|from_parent|
+        stringifier(from_parent, to_parent);
+    };
+    comm::send(to_child, 22u);
+    assert comm::recv(from_child) == "22";
+    comm::send(to_child, 23u);
+    assert comm::recv(from_child) == "23";
+    comm::send(to_child, 0u);
+    assert comm::recv(from_child) == "0";
+}
+~~~~
+
+The parent first sets up a port to receive data from and a channel
+that the child can use to send data to that port. The call to
+`spawn_listener()` will spawn the child task, providing it with a port
+on which to receive data from its parent, and returning to the parent
+the associated channel. Finally, the closure passed to
+`spawn_listener()` that forms the body of the child task captures the
+`to_parent` channel in its environment, so both parent and child
+can send and receive data to and from the other.
 
 ## The supervisor relationship
 

src/comp/driver/rustc.rs

@@ -143,8 +143,6 @@ fn monitor(f: fn~(diagnostic::emitter)) {
 
     alt task::try  {||
 
-        task::unsupervise();
-
         // The 'diagnostics emitter'. Every error, warning, etc. should
         // go through this function.
         let demitter = fn@(cmsp: option<(codemap::codemap, codemap::span)>,

src/compiletest/procsrv.rs

@@ -54,11 +54,11 @@ fn run(lib_path: str, prog: str, args: [str],
     writeclose(pipe_in.out, input);
     let p = comm::port();
     let ch = comm::chan(p);
-    task::spawn_sched(1u) {||
+    task::spawn_sched(task::single_threaded) {||
         let errput = readclose(pipe_err.in);
         comm::send(ch, (2, errput));
     };
-    task::spawn_sched(1u) {||
+    task::spawn_sched(task::single_threaded) {||
         let output = readclose(pipe_out.in);
         comm::send(ch, (1, output));
     };

src/libcore/comm.rs

@@ -35,8 +35,9 @@ enum rust_port {}
 
 #[abi = "cdecl"]
 native mod rustrt {
+    fn get_task_id() -> task_id;
     fn chan_id_send<T: send>(t: *sys::type_desc,
-                            target_task: task::task, target_port: port_id,
+                            target_task: task_id, target_port: port_id,
                             data: T) -> ctypes::uintptr_t;
 
     fn new_port(unit_sz: ctypes::size_t) -> *rust_port;
@@ -58,6 +59,7 @@ native mod rusti {
     fn call_with_retptr<T: send>(&&f: fn@(*uint)) -> T;
 }
 
+type task_id = int;
 type port_id = int;
 
 // It's critical that this only have one variant, so it has a record
@@ -75,7 +77,7 @@ type port_id = int;
           over other channels."
 )]
 enum chan<T: send> {
-    chan_t(task::task, port_id)
+    chan_t(task_id, port_id)
 }
 
 resource port_ptr<T: send>(po: *rust_port) {
@@ -208,7 +210,7 @@ fn peek<T: send>(p: port<T>) -> bool {
            port used to construct it."
 )]
 fn chan<T: send>(p: port<T>) -> chan<T> {
-    chan_t(task::get_task(), rustrt::get_port_id(***p))
+    chan_t(rustrt::get_task_id(), rustrt::get_port_id(***p))
 }
 
 #[test]