std: Change Times trait to use do instead of for

Change the former repetition::

    for 5.times { }

to::

    do 5.times { }

.times() cannot be broken with `break` or `return` anymore; for those
cases, use a numerical range loop instead.

doc/tutorial-tasks.md

@@ -548,7 +548,7 @@ an intermediate generation has already exited:
 ~~~
 # use std::task;
 # fn sleep_forever() { loop { task::yield() } }
-# fn wait_for_a_while() { for 1000.times { task::yield() } }
+# fn wait_for_a_while() { do 1000.times { task::yield() } }
 # do task::try::<int> {
 do task::spawn_supervised {
     do task::spawn_supervised {
@@ -567,7 +567,7 @@ other at all, using `task::spawn_unlinked` for _isolated failure_.
 ~~~
 # use std::task;
 # fn random() -> uint { 100 }
-# fn sleep_for(i: uint) { for i.times { task::yield() } }
+# fn sleep_for(i: uint) { do i.times { task::yield() } }
 # do task::try::<()> {
 let (time1, time2) = (random(), random());
 do task::spawn_unlinked {

doc/tutorial.md

@@ -1899,7 +1899,7 @@ struct TimeBomb {
 
 impl Drop for TimeBomb {
     fn drop(&self) {
-        for self.explosivity.times {
+        do self.explosivity.times {
             println("blam!");
         }
     }

src/libextra/arc.rs

@@ -23,7 +23,7 @@
  * let numbers=vec::from_fn(100, |ind| (ind as float)*rand::random());
  * let shared_numbers=arc::Arc::new(numbers);
  *
- *   for 10.times {
+ *   do 10.times {
  *       let (port, chan)  = stream();
  *       chan.send(shared_numbers.clone());
  *
@@ -765,7 +765,7 @@ mod tests {
 
         do task::spawn || {
             do arc2.write |num| {
-                for 10.times {
+                do 10.times {
                     let tmp = *num;
                     *num = -1;
                     task::yield();
@@ -777,7 +777,7 @@ mod tests {
 
         // Readers try to catch the writer in the act
         let mut children = ~[];
-        for 5.times {
+        do 5.times {
             let arc3 = (*arc).clone();
             let mut builder = task::task();
             builder.future_result(|r| children.push(r));
@@ -811,7 +811,7 @@ mod tests {
 
         // Reader tasks
         let mut reader_convos = ~[];
-        for 10.times {
+        do 10.times {
             let ((rp1,rc1),(rp2,rc2)) = (comm::stream(),comm::stream());
             reader_convos.push((rc1, rp2));
             let arcn = (*arc).clone();
@@ -925,7 +925,7 @@ mod tests {
             do read_mode.read |state| {
                 // if writer mistakenly got in, make sure it mutates state
                 // before we assert on it
-                for 5.times { task::yield(); }
+                do 5.times { task::yield(); }
                 // make sure writer didn't get in.
                 assert!(*state);
             }
@@ -937,6 +937,6 @@ mod tests {
         // helped to expose the race nearly 100% of the time... but adding
         // yields in the intuitively-right locations made it even less likely,
         // and I wasn't sure why :( . This is a mediocre "next best" option.
-        for 8.times { test_rw_write_cond_downgrade_read_race_helper() }
+        do 8.times { test_rw_write_cond_downgrade_read_race_helper() }
     }
 }

src/libextra/base64.rs

@@ -358,9 +358,9 @@ mod test {
         use std::rand::{task_rng, random, RngUtil};
         use std::vec;
 
-        for 1000.times {
+        do 1000.times {
             let v: ~[u8] = do vec::build |push| {
-                for task_rng().gen_uint_range(1, 100).times {
+                do task_rng().gen_uint_range(1, 100).times {
                     push(random());
                 }
             };
@@ -389,4 +389,4 @@ mod test {
         bh.bytes = b.len() as u64;
     }
 
-}
+}

src/libextra/bitv.rs

@@ -674,7 +674,7 @@ impl BitvSet {
     fn other_op(&mut self, other: &BitvSet, f: &fn(uint, uint) -> uint) {
         fn nbits(mut w: uint) -> uint {
             let mut bits = 0;
-            for uint::bits.times {
+            for uint::range(0, uint::bits) |_| {
                 if w == 0 {
                     break;
                 }

src/libextra/dlist.rs

@@ -933,7 +933,7 @@ mod tests {
 
     #[test]
     fn test_fuzz() {
-        for 25.times {
+        do 25.times {
             fuzz_test(3);
             fuzz_test(16);
             fuzz_test(189);

src/libextra/flate.rs

@@ -90,13 +90,13 @@ mod tests {
     fn test_flate_round_trip() {
         let mut r = rand::rng();
         let mut words = ~[];
-        for 20.times {
+        do 20.times {
             let range = r.gen_uint_range(1, 10);
             words.push(r.gen_bytes(range));
         }
-        for 20.times {
+        do 20.times {
             let mut input = ~[];
-            for 2000.times {
+            do 2000.times {
                 input.push_all(r.choose(words));
             }
             debug!("de/inflate of %u bytes of random word-sequences",

src/libextra/getopts.rs

@@ -662,7 +662,7 @@ pub mod groups {
             // here we just need to indent the start of the description
             let rowlen = row.len();
             if rowlen < 24 {
-                for (24 - rowlen).times {
+                do (24 - rowlen).times {
                     row.push_char(' ')
                 }
             } else {

src/libextra/json.rs

@@ -77,7 +77,7 @@ fn escape_str(s: &str) -> ~str {
 
 fn spaces(n: uint) -> ~str {
     let mut ss = ~"";
-    for n.times {
+    do n.times {
         ss.push_str(" ");
     }
     return ss;

src/libextra/ringbuf.rs

@@ -509,7 +509,7 @@ mod tests {
     fn bench_grow(b: &mut test::BenchHarness) {
         let mut deq = RingBuf::new();
         do b.iter {
-            for 65.times {
+            do 65.times {
                 deq.push_front(1);
             }
         }

src/libextra/sort.rs

@@ -1081,7 +1081,7 @@ mod big_tests {
             tim_sort(arr); // /sort
             isSorted(arr);
 
-            for 3.times {
+            do 3.times {
                 let i1 = rng.gen_uint_range(0, n);
                 let i2 = rng.gen_uint_range(0, n);
                 arr.swap(i1, i2);
@@ -1100,7 +1100,7 @@ mod big_tests {
             tim_sort(arr); // +sort
             isSorted(arr);
 
-            for (n/100).times {
+            do (n/100).times {
                 let idx = rng.gen_uint_range(0, n);
                 arr[idx] = rng.gen();
             }
@@ -1153,7 +1153,7 @@ mod big_tests {
             tim_sort(arr); // /sort
             isSorted(arr);
 
-            for 3.times {
+            do 3.times {
                 let i1 = rng.gen_uint_range(0, n);
                 let i2 = rng.gen_uint_range(0, n);
                 arr.swap(i1, i2);
@@ -1172,7 +1172,7 @@ mod big_tests {
             tim_sort(arr); // +sort
             isSorted(arr);
 
-            for (n/100).times {
+            do (n/100).times {
                 let idx = rng.gen_uint_range(0, n);
                 arr[idx] = @rng.gen();
             }

src/libextra/sync.rs

@@ -106,7 +106,7 @@ impl<Q:Send> Sem<Q> {
                 }
             }
             // Uncomment if you wish to test for sem races. Not valgrind-friendly.
-            /* for 1000.times { task::yield(); } */
+            /* do 1000.times { task::yield(); } */
             // Need to wait outside the exclusive.
             if waiter_nobe.is_some() {
                 let _ = comm::recv_one(waiter_nobe.unwrap());
@@ -143,7 +143,7 @@ impl Sem<~[WaitQueue]> {
     fn new_and_signal(count: int, num_condvars: uint)
         -> Sem<~[WaitQueue]> {
         let mut queues = ~[];
-        for num_condvars.times {
+        do num_condvars.times {
             queues.push(WaitQueue::new());
         }
         Sem::new(count, queues)
@@ -826,11 +826,11 @@ mod tests {
         let s2 = ~s.clone();
         do task::spawn || {
             do s2.access {
-                for 5.times { task::yield(); }
+                do 5.times { task::yield(); }
             }
         }
         do s.access {
-            for 5.times { task::yield(); }
+            do 5.times { task::yield(); }
         }
     }
     #[test]
@@ -843,7 +843,7 @@ mod tests {
             s2.acquire();
             c.send(());
         }
-        for 5.times { task::yield(); }
+        do 5.times { task::yield(); }
         s.release();
         let _ = p.recv();
 
@@ -852,7 +852,7 @@ mod tests {
         let s = ~Semaphore::new(0);
         let s2 = ~s.clone();
         do task::spawn || {
-            for 5.times { task::yield(); }
+            do 5.times { task::yield(); }
             s2.release();
             let _ = p.recv();
         }
@@ -895,7 +895,7 @@ mod tests {
                     c.send(());
                 }
                 let _ = p.recv(); // wait for child to come alive
-                for 5.times { task::yield(); } // let the child contend
+                do 5.times { task::yield(); } // let the child contend
             }
             let _ = p.recv(); // wait for child to be done
         }
@@ -929,7 +929,7 @@ mod tests {
         }
 
         fn access_shared(sharedstate: &mut int, m: &Mutex, n: uint) {
-            for n.times {
+            do n.times {
                 do m.lock {
                     let oldval = *sharedstate;
                     task::yield();
@@ -975,7 +975,7 @@ mod tests {
         let m = ~Mutex::new();
         let mut ports = ~[];
 
-        for num_waiters.times {
+        do num_waiters.times {
             let mi = ~m.clone();
             let (port, chan) = comm::stream();
             ports.push(port);
@@ -1065,7 +1065,7 @@ mod tests {
 
         let result: result::Result<(),()> = do task::try || {
             let mut sibling_convos = ~[];
-            for 2.times {
+            do 2.times {
                 let (p,c) = comm::stream();
                 let c = Cell::new(c);
                 sibling_convos.push(p);
@@ -1212,7 +1212,7 @@ mod tests {
 
         fn access_shared(sharedstate: &mut int, x: &RWLock, mode: RWLockMode,
                          n: uint) {
-            for n.times {
+            do n.times {
                 do lock_rwlock_in_mode(x, mode) {
                     let oldval = *sharedstate;
                     task::yield();
@@ -1343,7 +1343,7 @@ mod tests {
         let x = ~RWLock::new();
         let mut ports = ~[];
 
-        for num_waiters.times {
+        do num_waiters.times {
             let xi = (*x).clone();
             let (port, chan) = comm::stream();
             ports.push(port);

src/libextra/task_pool.rs

@@ -102,7 +102,7 @@ fn test_task_pool() {
         g
     };
     let mut pool = TaskPool::new(4, Some(SingleThreaded), f);
-    for 8.times {
+    do 8.times {
         pool.execute(|i| printfln!("Hello from thread %u!", *i));
     }
 }

src/libextra/tempfile.rs

@@ -14,12 +14,13 @@
 use std::os;
 use std::rand::RngUtil;
 use std::rand;
+use std::uint;
 
 /// Attempts to make a temporary directory inside of `tmpdir` whose name will
 /// have the suffix `suffix`. If no directory can be created, None is returned.
 pub fn mkdtemp(tmpdir: &Path, suffix: &str) -> Option<Path> {
     let mut r = rand::rng();
-    for 1000.times {
+    for uint::range(0, 1000) |_| {
         let p = tmpdir.push(r.gen_str(16) + suffix);
         if os::make_dir(&p, 0x1c0) { // 700
             return Some(p);

src/libextra/treemap.rs

@@ -16,6 +16,7 @@
 use std::num;
 use std::util::{swap, replace};
 use std::iterator::{FromIterator, Extendable};
+use std::uint;
 
 // This is implemented as an AA tree, which is a simplified variation of
 // a red-black tree where red (horizontal) nodes can only be added
@@ -47,7 +48,7 @@ impl<K: Eq + TotalOrd, V: Eq> Eq for TreeMap<K, V> {
         } else {
             let mut x = self.iter();
             let mut y = other.iter();
-            for self.len().times {
+            for uint::range(0, self.len()) |_| {
                 if x.next().unwrap() != y.next().unwrap() {
                     return false
                 }
@@ -65,7 +66,7 @@ fn lt<K: Ord + TotalOrd, V: Ord>(a: &TreeMap<K, V>,
     let mut y = b.iter();
 
     let (a_len, b_len) = (a.len(), b.len());
-    for num::min(a_len, b_len).times {
+    for uint::range(0, num::min(a_len, b_len)) |_| {
         let (key_a, value_a) = x.next().unwrap();
         let (key_b, value_b) = y.next().unwrap();
         if *key_a < *key_b { return true; }
@@ -931,8 +932,8 @@ mod test_treemap {
 
         let mut rng = rand::IsaacRng::new_seeded(&[42]);
 
-        for 3.times {
+        do 3.times {
-            for 90.times {
+            do 90.times {
                 let k = rng.gen();
                 let v = rng.gen();
                 if !ctrl.iter().any(|x| x == &(k, v)) {
@@ -943,7 +944,7 @@ mod test_treemap {
                 }
             }
 
-            for 30.times {
+            do 30.times {
                 let r = rng.gen_uint_range(0, ctrl.len());
                 let (key, _) = ctrl.remove(r);
                 assert!(map.remove(&key));

src/librustc/middle/dataflow.rs

@@ -189,7 +189,7 @@ impl<O:DataFlowOperator> DataFlowContext<O> {
         };
         if expanded {
             let entry = if self.oper.initial_value() { uint::max_value } else {0};
-            for self.words_per_id.times {
+            do self.words_per_id.times {
                 self.gens.push(0);
                 self.kills.push(0);
                 self.on_entry.push(entry);

src/librustc/middle/lint.rs

@@ -451,7 +451,7 @@ impl Context {
         if doc_hidden && self.doc_hidden {
             self.doc_hidden = false;
         }
-        for pushed.times {
+        do pushed.times {
             let (lint, lvl, src) = self.lint_stack.pop();
             self.set_level(lint, lvl, src);
         }

src/librustc/middle/privacy.rs

@@ -340,7 +340,7 @@ pub fn check_crate<'mm>(tcx: ty::ctxt,
 
             visit::visit_mod(the_module, span, node_id, (method_map, visitor));
 
-            for n_added.times {
+            do n_added.times {
                 ignore(privileged_items.pop());
             }
         },
@@ -370,7 +370,7 @@ pub fn check_crate<'mm>(tcx: ty::ctxt,
 
             visit::visit_block(block, (method_map, visitor));
 
-            for n_added.times {
+            do n_added.times {
                 ignore(privileged_items.pop());
             }
         },

src/librustc/middle/trans/consts.rs

@@ -188,7 +188,7 @@ pub fn const_expr(cx: @mut CrateContext, e: @ast::expr) -> ValueRef {
         Some(@ty::AutoDerefRef(ref adj)) => {
             let mut ty = ety;
             let mut maybe_ptr = None;
-            for adj.autoderefs.times {
+            do adj.autoderefs.times {
                 let (dv, dt) = const_deref(cx, llconst, ty, false);
                 maybe_ptr = Some(llconst);
                 llconst = dv;

src/librustdoc/markdown_pass.rs

@@ -637,7 +637,7 @@ mod test {
         let doc = (page_pass::mk_pass(config::DocPerMod).f)(srv, doc);
         write_markdown(doc, writer_factory);
         // We expect two pages to have been written
-        for 2.times {
+        do 2.times {
             po.recv();
         }
     }
@@ -649,7 +649,7 @@ mod test {
             ~"#[link(name = \"core\")]; mod a { }");
         let doc = (page_pass::mk_pass(config::DocPerMod).f)(srv, doc);
         write_markdown(doc, writer_factory);
-        for 2.times {
+        do 2.times {
             let (page, markdown) = po.recv();
             match page {
                 doc::CratePage(_) => {

src/libstd/iter.rs

@@ -14,13 +14,13 @@
 use iter::Times;
 let ten = 10 as uint;
 let mut accum = 0;
-for ten.times { accum += 1; }
+do ten.times { accum += 1; }
 ~~~
 
 */
 
 #[allow(missing_doc)]
 pub trait Times {
-    fn times(&self, it: &fn() -> bool) -> bool;
+    fn times(&self, it: &fn());
 }
 

src/libstd/iterator.rs

@@ -18,7 +18,6 @@ implementing the `Iterator` trait.
 */
 
 use cmp;
-use iter::Times;
 use num::{Zero, One};
 use option::{Option, Some, None};
 use ops::{Add, Mul};
@@ -1229,8 +1228,9 @@ impl<A, T: Iterator<A>> Iterator<A> for Skip<T> {
         if self.n == 0 {
             next
         } else {
-            let n = self.n;
+            let mut n = self.n;
-            for n.times {
+            while n > 0 {
+                n -= 1;
                 match next {
                     Some(_) => {
                         next = self.iter.next();

src/libstd/num/uint.rs

@@ -97,22 +97,21 @@ pub fn iterate(lo: uint, hi: uint, it: &fn(uint) -> bool) -> bool {
 impl iter::Times for uint {
     #[inline]
     ///
-    /// A convenience form for basic iteration. Given a uint `x`,
+    /// A convenience form for basic repetition. Given a uint `x`,
-    /// `for x.times { ... }` executes the given block x times.
+    /// `do x.times { ... }` executes the given block x times.
     ///
     /// Equivalent to `for uint::range(0, x) |_| { ... }`.
     ///
     /// Not defined on all integer types to permit unambiguous
     /// use with integer literals of inferred integer-type as
-    /// the self-value (eg. `for 100.times { ... }`).
+    /// the self-value (eg. `do 100.times { ... }`).
     ///
-    fn times(&self, it: &fn() -> bool) -> bool {
+    fn times(&self, it: &fn()) {
         let mut i = *self;
         while i > 0 {
-            if !it() { return false; }
+            it();
             i -= 1;
         }
-        return true;
     }
 }
 
@@ -190,6 +189,6 @@ pub fn test_times() {
     use iter::Times;
     let ten = 10 as uint;
     let mut accum = 0;
-    for ten.times { accum += 1; }
+    do ten.times { accum += 1; }
     assert!((accum == 10));
 }

src/libstd/rand.rs

@@ -695,7 +695,7 @@ impl IsaacRng {
             }}
         );
 
-        for 4.times { mix!(); }
+        do 4.times { mix!(); }
 
         if use_rsl {
             macro_rules! memloop (
@@ -1092,7 +1092,7 @@ mod test {
         }
 
         // run against several seeds
-        for 10.times {
+        do 10.times {
             unsafe {
                 let seed = super::seed();
                 let rt_rng = do seed.as_imm_buf |p, sz| {
@@ -1100,7 +1100,7 @@ mod test {
                 };
                 let mut rng = IsaacRng::new_seeded(seed);
 
-                for 10000.times {
+                do 10000.times {
                     assert_eq!(rng.next(), rustrt::rand_next(rt_rng));
                 }
                 rustrt::rand_free(rt_rng);

src/libstd/rt/comm.rs

@@ -769,7 +769,7 @@ mod test {
 
     #[test]
     fn oneshot_multi_thread_close_stress() {
-        for stress_factor().times {
+        do stress_factor().times {
             do run_in_newsched_task {
                 let (port, chan) = oneshot::<int>();
                 let port_cell = Cell::new(port);
@@ -784,7 +784,7 @@ mod test {
 
     #[test]
     fn oneshot_multi_thread_send_close_stress() {
-        for stress_factor().times {
+        do stress_factor().times {
             do run_in_newsched_task {
                 let (port, chan) = oneshot::<int>();
                 let chan_cell = Cell::new(chan);
@@ -804,7 +804,7 @@ mod test {
 
     #[test]
     fn oneshot_multi_thread_recv_close_stress() {
-        for stress_factor().times {
+        do stress_factor().times {
             do run_in_newsched_task {
                 let (port, chan) = oneshot::<int>();
                 let chan_cell = Cell::new(chan);
@@ -830,7 +830,7 @@ mod test {
 
     #[test]
     fn oneshot_multi_thread_send_recv_stress() {
-        for stress_factor().times {
+        do stress_factor().times {
             do run_in_newsched_task {
                 let (port, chan) = oneshot::<~int>();
                 let chan_cell = Cell::new(chan);
@@ -849,7 +849,7 @@ mod test {
 
     #[test]
     fn stream_send_recv_stress() {
-        for stress_factor().times {
+        do stress_factor().times {
             do run_in_mt_newsched_task {
                 let (port, chan) = stream::<~int>();
 
@@ -886,8 +886,8 @@ mod test {
         // Regression test that we don't run out of stack in scheduler context
         do run_in_newsched_task {
             let (port, chan) = stream();
-            for 10000.times { chan.send(()) }
+            do 10000.times { chan.send(()) }
-            for 10000.times { port.recv() }
+            do 10000.times { port.recv() }
         }
     }
 
@@ -897,14 +897,14 @@ mod test {
             let (port, chan) = stream();
             let chan = SharedChan::new(chan);
             let total = stress_factor() + 100;
-            for total.times {
+            do total.times {
                 let chan_clone = chan.clone();
                 do spawntask_random {
                     chan_clone.send(());
                 }
             }
 
-            for total.times {
+            do total.times {
                 port.recv();
             }
         }
@@ -919,7 +919,7 @@ mod test {
             let end_chan = SharedChan::new(end_chan);
             let port = SharedPort::new(port);
             let total = stress_factor() + 100;
-            for total.times {
+            do total.times {
                 let end_chan_clone = end_chan.clone();
                 let port_clone = port.clone();
                 do spawntask_random {
@@ -928,11 +928,11 @@ mod test {
                 }
             }
 
-            for total.times {
+            do total.times {
                 chan.send(());
             }
 
-            for total.times {
+            do total.times {
                 end_port.recv();
             }
         }
@@ -959,7 +959,7 @@ mod test {
             let send_total = 10;
             let recv_total = 20;
             do spawntask_random {
-                for send_total.times {
+                do send_total.times {
                     let chan_clone = chan.clone();
                     do spawntask_random {
                         chan_clone.send(());
@@ -968,7 +968,7 @@ mod test {
             }
             let end_chan_clone = end_chan.clone();
             do spawntask_random {
-                for recv_total.times {
+                do recv_total.times {
                     let port_clone = port.clone();
                     let end_chan_clone = end_chan_clone.clone();
                     do spawntask_random {
@@ -979,7 +979,7 @@ mod test {
             }
 
             let mut recvd = 0;
-            for recv_total.times {
+            do recv_total.times {
                 recvd += if end_port.recv() { 1 } else { 0 };
             }
 
@@ -998,15 +998,15 @@ mod test {
             let pipe = megapipe();
             let total = stress_factor() + 10;
             let mut rng = rand::rng();
-            for total.times {
+            do total.times {
                 let msgs = rng.gen_uint_range(0, 10);
                 let pipe_clone = pipe.clone();
                 let end_chan_clone = end_chan.clone();
                 do spawntask_random {
-                    for msgs.times {
+                    do msgs.times {
                         pipe_clone.send(());
                     }
-                    for msgs.times {
+                    do msgs.times {
                         pipe_clone.recv();
                     }
                 }
@@ -1014,7 +1014,7 @@ mod test {
                 end_chan_clone.send(());
             }
 
-            for total.times {
+            do total.times {
                 end_port.recv();
             }
         }

src/libstd/rt/io/net/tcp.rs

@@ -371,7 +371,7 @@ mod test {
 
             do spawntask_immediately {
                 let mut listener = TcpListener::bind(addr);
-                for max.times {
+                do max.times {
                     let mut stream = listener.accept();
                     let mut buf = [0];
                     stream.read(buf);
@@ -380,7 +380,7 @@ mod test {
             }
 
             do spawntask_immediately {
-                for max.times {
+                do max.times {
                     let mut stream = TcpStream::connect(addr);
                     stream.write([99]);
                 }
@@ -396,7 +396,7 @@ mod test {
 
             do spawntask_immediately {
                 let mut listener = TcpListener::bind(addr);
-                for max.times {
+                do max.times {
                     let mut stream = listener.accept();
                     let mut buf = [0];
                     stream.read(buf);
@@ -405,7 +405,7 @@ mod test {
             }
 
             do spawntask_immediately {
-                for max.times {
+                do max.times {
                     let mut stream = TcpStream::connect(addr);
                     stream.write([99]);
                 }

src/libstd/rt/mod.rs

@@ -255,7 +255,7 @@ fn run_(main: ~fn(), use_main_sched: bool) -> int {
     // sent the Shutdown message to terminate the schedulers.
     let mut handles = ~[];
 
-    for nscheds.times {
+    do nscheds.times {
         // Every scheduler is driven by an I/O event loop.
         let loop_ = ~UvEventLoop::new();
         let mut sched = ~Scheduler::new(loop_, work_queue.clone(), sleepers.clone());

src/libstd/rt/sched.rs

@@ -1097,7 +1097,7 @@ mod test {
 
         do run_in_mt_newsched_task {
             let mut ports = ~[];
-            for 10.times {
+            do 10.times {
                 let (port, chan) = oneshot();
                 let chan_cell = Cell::new(chan);
                 do spawntask_later {

src/libstd/rt/select.rs

@@ -187,7 +187,7 @@ mod test {
         do run_in_newsched_task {
             let (ports, _) = unzip(from_fn(10, |_| stream()));
             let (port, chan) = stream();
-            for 10.times { chan.send(31337); }
+            do 10.times { chan.send(31337); }
             let mut ports = ports;
             let mut port = Some(port);
             let order = [5u,0,4,3,2,6,9,8,7,1];
@@ -268,7 +268,7 @@ mod test {
 
             do run_in_newsched_task {
                 // A bit of stress, since ordinarily this is just smoke and mirrors.
-                for 4.times {
+                do 4.times {
                     let send_on_chans = send_on_chans.clone();
                     do task::spawn {
                         let mut ports = ~[];

src/libstd/str.rs

@@ -1828,7 +1828,7 @@ impl<'self> StrSlice<'self> for &'self str {
                 do ret.as_mut_buf |rbuf, _len| {
                     let mut rbuf = rbuf;
 
-                    for nn.times {
+                    do nn.times {
                         ptr::copy_memory(rbuf, buf, len);
                         rbuf = rbuf.offset(len as int);
                     }

src/libstd/task/mod.rs

@@ -683,7 +683,7 @@ fn test_spawn_unlinked_unsup_no_fail_down() { // grandchild sends on a port
         let ch = ch.clone();
         do spawn_unlinked {
             // Give middle task a chance to fail-but-not-kill-us.
-            for 16.times { task::yield(); }
+            do 16.times { task::yield(); }
             ch.send(()); // If killed first, grandparent hangs.
         }
         fail!(); // Shouldn't kill either (grand)parent or (grand)child.
@@ -698,7 +698,7 @@ fn test_spawn_unlinked_unsup_no_fail_up() { // child unlinked fails
 fn test_spawn_unlinked_sup_no_fail_up() { // child unlinked fails
     do spawn_supervised { fail!(); }
     // Give child a chance to fail-but-not-kill-us.
-    for 16.times { task::yield(); }
+    do 16.times { task::yield(); }
 }
 #[test] #[should_fail] #[ignore(cfg(windows))]
 fn test_spawn_unlinked_sup_fail_down() {
@@ -760,7 +760,7 @@ fn test_spawn_failure_propagate_grandchild() {
     do spawn_supervised {
         do spawn_supervised { block_forever(); }
     }
-    for 16.times { task::yield(); }
+    do 16.times { task::yield(); }
     fail!();
 }
 
@@ -770,7 +770,7 @@ fn test_spawn_failure_propagate_secondborn() {
     do spawn_supervised {
         do spawn { block_forever(); } // linked
     }
-    for 16.times { task::yield(); }
+    do 16.times { task::yield(); }
     fail!();
 }
 
@@ -780,7 +780,7 @@ fn test_spawn_failure_propagate_nephew_or_niece() {
     do spawn { // linked
         do spawn_supervised { block_forever(); }
     }
-    for 16.times { task::yield(); }
+    do 16.times { task::yield(); }
     fail!();
 }
 
@@ -790,7 +790,7 @@ fn test_spawn_linked_sup_propagate_sibling() {
     do spawn { // linked
         do spawn { block_forever(); } // linked
     }
-    for 16.times { task::yield(); }
+    do 16.times { task::yield(); }
     fail!();
 }
 
@@ -970,7 +970,7 @@ fn test_spawn_sched_blocking() {
 
         // Testing that a task in one scheduler can block in foreign code
         // without affecting other schedulers
-        for 20u.times {
+        do 20u.times {
             let (start_po, start_ch) = stream();
             let (fin_po, fin_ch) = stream();
 
@@ -1076,7 +1076,7 @@ fn test_unkillable() {
 
     // We want to do this after failing
     do spawn_unlinked {
-        for 10.times { yield() }
+        do 10.times { yield() }
         ch.send(());
     }
 
@@ -1111,7 +1111,7 @@ fn test_unkillable_nested() {
 
     // We want to do this after failing
     do spawn_unlinked || {
-        for 10.times { yield() }
+        do 10.times { yield() }
         ch.send(());
     }
 

src/libstd/unstable/extfmt.rs

@@ -636,7 +636,7 @@ pub mod rt {
                 buf.push_char(c);
             }
             buf.push_str(s);
-            for diff.times {
+            do diff.times {
                 buf.push_char(padchar);
             }
             return;

src/libstd/unstable/sync.rs

@@ -626,7 +626,7 @@ mod tests {
             let x = Exclusive::new(~~"hello");
             let x2 = x.clone();
             do task::spawn {
-                for 10.times { task::yield(); } // try to let the unwrapper go
+                do 10.times { task::yield(); } // try to let the unwrapper go
                 fail!(); // punt it awake from its deadlock
             }
             let _z = x.unwrap();

src/libsyntax/diagnostic.rs

@@ -302,7 +302,7 @@ fn highlight_lines(cm: @codemap::CodeMap,
         // Skip is the number of characters we need to skip because they are
         // part of the 'filename:line ' part of the previous line.
         let skip = fm.name.len() + digits + 3u;
-        for skip.times() {
+        do skip.times() {
             s.push_char(' ');
         }
         let orig = fm.get_line(lines.lines[0] as int);
@@ -323,7 +323,7 @@ fn highlight_lines(cm: @codemap::CodeMap,
         if hi.col != lo.col {
             // the ^ already takes up one space
             let num_squigglies = hi.col.to_uint()-lo.col.to_uint()-1u;
-            for num_squigglies.times() {
+            do num_squigglies.times() {
                 s.push_char('~')
             }
         }

src/libsyntax/ext/tt/macro_parser.rs

@@ -403,7 +403,7 @@ pub fn parse(
                 }
                 cur_eis.push(ei);
 
-                for rust_parser.tokens_consumed.times() || {
+                do rust_parser.tokens_consumed.times() || {
                     rdr.next_token();
                 }
             }

src/test/bench/core-set.rs

@@ -59,7 +59,7 @@ impl Results {
         {
             let mut set = f();
             do timed(&mut self.random_ints) {
-                for num_keys.times {
+                do num_keys.times {
                     set.insert((rng.next() as uint) % rand_cap);
                 }
             }
@@ -103,7 +103,7 @@ impl Results {
         {
             let mut set = f();
             do timed(&mut self.random_strings) {
-                for num_keys.times {
+                do num_keys.times {
                     let s = uint::to_str(rng.next() as uint);
                     set.insert(s);
                 }

src/test/bench/noise.rs

@@ -105,7 +105,7 @@ fn main() {
     let symbols = [" ", "░", "▒", "▓", "█", "█"];
     let mut pixels = [0f32, ..256*256];
     let n2d = ~Noise2DContext::new();
-    for 100.times {
+    do 100.times {
         for int::range(0, 256) |y| {
             for int::range(0, 256) |x| {
                 let v = n2d.get(

src/test/bench/shootout-chameneos-redux.rs

@@ -169,7 +169,7 @@ fn rendezvous(nn: uint, set: ~[color]) {
     let mut creatures_met = 0;
 
     // set up meetings...
-    for nn.times {
+    do nn.times {
         let fst_creature: CreatureInfo = from_creatures.recv();
         let snd_creature: CreatureInfo = from_creatures.recv();
 

src/test/bench/shootout-fasta-redux.rs

@@ -164,7 +164,7 @@ impl RandomFasta {
             let chars_left = n % LINE_LEN;
             let mut buf = [0, ..LINE_LEN + 1];
 
-            for lines.times {
+            do lines.times {
                 for range(0, LINE_LEN) |i| {
                     buf[i] = self.nextc();
                 }

src/test/bench/shootout-k-nucleotide.rs

@@ -54,7 +54,7 @@ impl Code {
     fn unpack(&self, frame: i32) -> ~str {
         let mut key = **self;
         let mut result = ~[];
-        for (frame as uint).times {
+        do (frame as uint).times {
             result.push(unpack_symbol((key as u8) & 3));
             key >>= 2;
         }
@@ -251,7 +251,7 @@ fn generate_frequencies(frequencies: &mut Table,
     let mut code = Code(0);
 
     // Pull first frame.
-    for (frame as uint).times {
+    do (frame as uint).times {
         code = code.push_char(input[0]);
         input = next_char(input);
     }

src/test/bench/shootout-mandelbrot.rs

@@ -30,7 +30,7 @@ fn main() {
                 let Cr = 2.0 * (x as f64) / (w as f64) - 1.5;
                 let Ci = 2.0 * (y as f64) / (h as f64) - 1.0;
 
-                for ITER.times {
+                for range(0, ITER as i32) |_| {
                     if Tr + Ti > LIMIT * LIMIT {
                         break;
                     }

src/test/bench/shootout-nbody.rs

@@ -80,7 +80,7 @@ struct Planet {
 
 fn advance(bodies: &mut [Planet, ..N_BODIES], dt: f64, steps: i32) {
     let mut d = [ 0.0, ..3 ];
-    for (steps as uint).times {
+    do (steps as uint).times {
         for range(0, N_BODIES) |i| {
             for range(i + 1, N_BODIES) |j| {
                 d[0] = bodies[i].x[0] - bodies[j].x[0];

src/test/bench/shootout-spectralnorm.rs

@@ -56,7 +56,7 @@ fn main() {
     let mut u = vec::from_elem(n, 1f64);
     let mut v = u.clone();
     let mut tmp = u.clone();
-    for 8.times {
+    do 8.times {
         mult_AtAv(u, v, tmp);
         mult_AtAv(v, u, tmp);
     }

src/test/bench/task-perf-alloc-unwind.rs

@@ -32,7 +32,7 @@ fn main() {
 }
 
 fn run(repeat: int, depth: int) {
-    for (repeat as uint).times {
+    do (repeat as uint).times {
         info!("starting %.4f", precise_time_s());
         do task::try {
             recurse_or_fail(depth, None)

src/test/bench/task-perf-linked-failure.rs

@@ -32,7 +32,7 @@ fn grandchild_group(num_tasks: uint) {
     let (po, ch) = stream();
     let ch = SharedChan::new(ch);
 
-    for num_tasks.times {
+    do num_tasks.times {
         let ch = ch.clone();
         do task::spawn { // linked
             ch.send(());
@@ -41,7 +41,7 @@ fn grandchild_group(num_tasks: uint) {
         }
     }
     error!("Grandchild group getting started");
-    for num_tasks.times {
+    do num_tasks.times {
         // Make sure all above children are fully spawned; i.e., enlisted in
         // their ancestor groups.
         po.recv();

src/test/compile-fail/block-must-not-have-result-for.rs

@@ -1,15 +0,0 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-fn main() {
-    for 2.times {  //~ ERROR A for-loop body must return (), but
-        true
-    }
-}

src/test/compile-fail/borrowck-lend-flow-loop.rs

@@ -40,7 +40,7 @@ fn block_overarching_alias_mut() {
 
     let mut v = ~3;
     let mut x = &mut v;
-    for 3.times {
+    do 3.times {
         borrow(v); //~ ERROR cannot borrow
     }
     *x = ~5;

src/test/compile-fail/issue-3651-2.rs

@@ -9,5 +9,6 @@
 // except according to those terms.
 
 fn main() {
-    do 5.times {}; //~ ERROR Do-block body must return bool, but returns () here. Perhaps
+    fn take_block(f: &fn() -> bool) -> bool { f() }
+    do take_block {}; //~ ERROR Do-block body must return bool, but returns () here. Perhaps
 }

src/test/run-fail/extern-fail.rs

@@ -40,7 +40,7 @@ fn count(n: uint) -> uint {
 }
 
 fn main() {
-    for 10u.times {
+    do 10u.times {
         do task::spawn {
             let result = count(5u);
             info!("result = %?", result);

src/test/run-pass/bitv-perf-test.rs

@@ -13,11 +13,10 @@
 extern mod extra;
 use extra::bitv::*;
 
-fn bitv_test() -> bool {
+fn bitv_test() {
     let mut v1 = ~Bitv::new(31, false);
     let v2 = ~Bitv::new(31, true);
     v1.union(v2);
-    true
 }
 
 pub fn main() {

src/test/run-pass/deriving-encodable-decodable.rs

@@ -69,7 +69,7 @@ pub fn main() {
     roundtrip::<C>();
     roundtrip::<D>();
 
-    for 20.times {
+    do 20.times {
         roundtrip::<E>();
         roundtrip::<F>();
         roundtrip::<G<int>>();

src/test/run-pass/deriving-rand.rs

@@ -32,7 +32,7 @@ enum D {
 
 fn main() {
     // check there's no segfaults
-    for 20.times {
+    do 20.times {
         rand::random::<A>();
         rand::random::<B>();
         rand::random::<C>();

src/test/run-pass/extern-stress.rs

@@ -39,7 +39,7 @@ fn count(n: uint) -> uint {
 }
 
 pub fn main() {
-    for 100u.times {
+    do 100u.times {
         do task::spawn {
             assert_eq!(count(5u), 16u);
         };

src/test/run-pass/extern-yield.rs

@@ -36,7 +36,7 @@ fn count(n: uint) -> uint {
 }
 
 pub fn main() {
-    for 10u.times {
+    do 10u.times {
         do task::spawn {
             let result = count(5u);
             info!("result = %?", result);

src/test/run-pass/issue-3211.rs

@@ -1,6 +1,6 @@
 pub fn main() {
     let mut x = 0;
-    for 4096.times {
+    do 4096.times {
         x += 1;
     }
     assert_eq!(x, 4096);

src/test/run-pass/issue-3563-3.rs

@@ -68,7 +68,7 @@ fn AsciiArt(width: uint, height: uint, fill: char) -> AsciiArt {
     // Use an anonymous function to build a vector of vectors containing
     // blank characters for each position in our canvas.
     let mut lines = do vec::build_sized(height) |push| {
-            for height.times {
+            do height.times {
                 push(vec::from_elem(width, '.'));
             }
         };

src/test/run-pass/issue-4241.rs

@@ -45,7 +45,7 @@ priv fn parse_data(len: uint, io: @io::Reader) -> Result {
 
 priv fn parse_list(len: uint, io: @io::Reader) -> Result {
   let mut list: ~[Result] = ~[];
-    for len.times {
+    do len.times {
     let v =
         match io.read_char() {
         '$' => parse_bulk(io),

src/test/run-pass/issue-4401.rs

@@ -1,6 +1,6 @@
 pub fn main() {
     let mut count = 0;
-    for 999_999.times() {
+    do 999_999.times() {
         count += 1;
     }
     assert_eq!(count, 999_999);

src/test/run-pass/issue-5321-immediates-with-bare-self.rs

@@ -14,7 +14,7 @@ trait Fooable {
 
 impl Fooable for uint {
     fn yes(self) {
-        for self.times {
+        do self.times {
             println("yes");
         }
     }

src/test/run-pass/numeric-method-autoexport.rs

@@ -32,7 +32,7 @@ pub fn main() {
     assert_eq!(15u64.add(&6u64), 21u64);
 
     // times
-     15u.times(|| false);
+     15u.times(|| {});
 
 // floats
     // num

src/test/run-pass/syntax-extension-fmt.rs

@@ -266,7 +266,7 @@ fn more_floats() {
 }
 
 fn pointer() {
-    for 10.times {
+    do 10.times {
         let x: uint = ::std::rand::random();
         assert_eq!(fmt!("%p", x as *uint), fmt!("0x%x", x));
     }