diff --git a/src/libstd/io/stdio.rs b/src/libstd/io/stdio.rs
index 43d2e078035..b7d069eb19e 100644
--- a/src/libstd/io/stdio.rs
+++ b/src/libstd/io/stdio.rs
@@ -334,7 +334,7 @@ pub fn set_stderr(stderr: Box<Writer + Send>) -> Option<Box<Writer + Send>> {
 //          // io1 aliases io2
 //      })
 //  })
-fn with_task_stdout(f: |&mut Writer| -> IoResult<()>) {
+fn with_task_stdout<F>(f: F) where F: FnOnce(&mut Writer) -> IoResult<()> {
     let mut my_stdout = LOCAL_STDOUT.with(|slot| {
         slot.borrow_mut().take()
     }).unwrap_or_else(|| {
diff --git a/src/libstd/rt/task.rs b/src/libstd/rt/task.rs
index 773322e4f57..41e91d1b6ef 100644
--- a/src/libstd/rt/task.rs
+++ b/src/libstd/rt/task.rs
@@ -174,7 +174,7 @@ impl Task {
     ///
     /// It is invalid to call this function with a thread that has been previously
     /// destroyed via a failed call to `run`.
-    pub fn run(mut self: Box<Task>, f: ||) -> Box<Task> {
+    pub fn run<F>(mut self: Box<Task>, f: F) -> Box<Task> where F: FnOnce() {
         assert!(!self.is_destroyed(), "cannot re-use a destroyed thread");
 
         // First, make sure that no one else is in TLS. This does not allow
diff --git a/src/libstd/sys/common/thread_info.rs b/src/libstd/sys/common/thread_info.rs
index dc21feb17a8..8c76eb1504d 100644
--- a/src/libstd/sys/common/thread_info.rs
+++ b/src/libstd/sys/common/thread_info.rs
@@ -26,13 +26,13 @@ struct ThreadInfo {
 thread_local! { static THREAD_INFO: RefCell<Option<ThreadInfo>> = RefCell::new(None) }
 
 impl ThreadInfo {
-    fn with<R>(f: |&mut ThreadInfo| -> R) -> R {
+    fn with<R, F>(f: F) -> R where F: FnOnce(&mut ThreadInfo) -> R {
         if THREAD_INFO.destroyed() {
             panic!("Use of std::thread::Thread::current() is not possible after \
                     the thread's local data has been destroyed");
         }
 
-        THREAD_INFO.with(|c| {
+        THREAD_INFO.with(move |c| {
             if c.borrow().is_none() {
                 *c.borrow_mut() = Some(ThreadInfo {
                     stack_bounds: (0, 0),
diff --git a/src/libstd/sys/windows/os.rs b/src/libstd/sys/windows/os.rs
index e7194df7ac3..0f26e36a80f 100644
--- a/src/libstd/sys/windows/os.rs
+++ b/src/libstd/sys/windows/os.rs
@@ -124,7 +124,9 @@ pub unsafe fn pipe() -> IoResult<(FileDesc, FileDesc)> {
     }
 }
 
-pub fn fill_utf16_buf_and_decode(f: |*mut u16, DWORD| -> DWORD) -> Option<String> {
+pub fn fill_utf16_buf_and_decode<F>(mut f: F) -> Option<String> where
+    F: FnMut(*mut u16, DWORD) -> DWORD,
+{
     unsafe {
         let mut n = TMPBUF_SZ as DWORD;
         let mut res = None;