libstd: changes to in response to #5656

7 files changed, 390 insertions, 14 deletions

diff --git a/src/libstd/arena.rs b/src/libstd/arena.rs
index 81c28f94d9f..3d2c3ac70b6 100644
--- a/src/libstd/arena.rs
+++ b/src/libstd/arena.rs
@@ -171,7 +171,7 @@ unsafe fn un_bitpack_tydesc_ptr(p: uint) -> (*TypeDesc, bool) {
 
 pub impl Arena {
     // Functions for the POD part of the arena
-    fn alloc_pod_grow(&self, n_bytes: uint, align: uint) -> *u8 {
+    priv fn alloc_pod_grow(&self, n_bytes: uint, align: uint) -> *u8 {
         // Allocate a new chunk.
         let chunk_size = at_vec::capacity(self.pod_head.data);
         let new_min_chunk_size = uint::max(n_bytes, chunk_size);
@@ -183,7 +183,7 @@ pub impl Arena {
     }
 
     #[inline(always)]
-    fn alloc_pod_inner(&self, n_bytes: uint, align: uint) -> *u8 {
+    priv fn alloc_pod_inner(&self, n_bytes: uint, align: uint) -> *u8 {
         let head = &mut self.pod_head;
 
         let start = round_up_to(head.fill, align);
@@ -202,7 +202,22 @@ pub impl Arena {
     }
 
     #[inline(always)]
-    fn alloc_pod<T>(&self, op: &fn() -> T) -> &'self T {
+    #[cfg(stage0)]
+    priv fn alloc_pod<T>(&self, op: &fn() -> T) -> &'self T {
+        unsafe {
+            let tydesc = sys::get_type_desc::<T>();
+            let ptr = self.alloc_pod_inner((*tydesc).size, (*tydesc).align);
+            let ptr: *mut T = reinterpret_cast(&ptr);
+            rusti::move_val_init(&mut (*ptr), op());
+            return reinterpret_cast(&ptr);
+        }
+    }
+
+    #[inline(always)]
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    priv fn alloc_pod<'a, T>(&'a self, op: &fn() -> T) -> &'a T {
         unsafe {
             let tydesc = sys::get_type_desc::<T>();
             let ptr = self.alloc_pod_inner((*tydesc).size, (*tydesc).align);
@@ -213,7 +228,7 @@ pub impl Arena {
     }
 
     // Functions for the non-POD part of the arena
-    fn alloc_nonpod_grow(&self, n_bytes: uint, align: uint) -> (*u8, *u8) {
+    priv fn alloc_nonpod_grow(&self, n_bytes: uint, align: uint) -> (*u8, *u8) {
         // Allocate a new chunk.
         let chunk_size = at_vec::capacity(self.head.data);
         let new_min_chunk_size = uint::max(n_bytes, chunk_size);
@@ -225,7 +240,7 @@ pub impl Arena {
     }
 
     #[inline(always)]
-    fn alloc_nonpod_inner(&self, n_bytes: uint, align: uint) -> (*u8, *u8) {
+    priv fn alloc_nonpod_inner(&self, n_bytes: uint, align: uint) -> (*u8, *u8) {
         let head = &mut self.head;
 
         let tydesc_start = head.fill;
@@ -247,7 +262,32 @@ pub impl Arena {
     }
 
     #[inline(always)]
-    fn alloc_nonpod<T>(&self, op: &fn() -> T) -> &'self T {
+    #[cfg(stage0)]
+    priv fn alloc_nonpod<T>(&self, op: &fn() -> T) -> &'self T {
+        unsafe {
+            let tydesc = sys::get_type_desc::<T>();
+            let (ty_ptr, ptr) =
+                self.alloc_nonpod_inner((*tydesc).size, (*tydesc).align);
+            let ty_ptr: *mut uint = reinterpret_cast(&ty_ptr);
+            let ptr: *mut T = reinterpret_cast(&ptr);
+            // Write in our tydesc along with a bit indicating that it
+            // has *not* been initialized yet.
+            *ty_ptr = reinterpret_cast(&tydesc);
+            // Actually initialize it
+            rusti::move_val_init(&mut(*ptr), op());
+            // Now that we are done, update the tydesc to indicate that
+            // the object is there.
+            *ty_ptr = bitpack_tydesc_ptr(tydesc, true);
+
+            return reinterpret_cast(&ptr);
+        }
+    }
+
+    #[inline(always)]
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    priv fn alloc_nonpod<'a, T>(&'a self, op: &fn() -> T) -> &'a T {
         unsafe {
             let tydesc = sys::get_type_desc::<T>();
             let (ty_ptr, ptr) =
@@ -269,6 +309,7 @@ pub impl Arena {
 
     // The external interface
     #[inline(always)]
+    #[cfg(stage0)]
     fn alloc<T>(&self, op: &fn() -> T) -> &'self T {
         unsafe {
             if !rusti::needs_drop::<T>() {
@@ -278,6 +319,21 @@ pub impl Arena {
             }
         }
     }
+
+    // The external interface
+    #[inline(always)]
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn alloc<'a, T>(&'a self, op: &fn() -> T) -> &'a T {
+        unsafe {
+            if !rusti::needs_drop::<T>() {
+                self.alloc_pod(op)
+            } else {
+                self.alloc_nonpod(op)
+            }
+        }
+    }
 }
 
 #[test]
diff --git a/src/libstd/bitv.rs b/src/libstd/bitv.rs
index f69e2130e71..632a38e8ca2 100644
--- a/src/libstd/bitv.rs
+++ b/src/libstd/bitv.rs
@@ -437,8 +437,7 @@ pub impl Bitv {
             if offset >= bitv.nbits {
                 0
             } else {
-                // NOTE cannot use bitv[offset] until snapshot
-                bitv.index(&offset) as u8 << (7 - bit)
+                bitv[offset] as u8 << (7 - bit)
             }
         }
 
@@ -460,8 +459,7 @@ pub impl Bitv {
      * Transform self into a [bool] by turning each bit into a bool
      */
     fn to_bools(&self) -> ~[bool] {
-        // NOTE cannot use self[i] until snapshot
-        vec::from_fn(self.nbits, |i| self.index(&i))
+        vec::from_fn(self.nbits, |i| self[i])
     }
 
     /**
diff --git a/src/libstd/deque.rs b/src/libstd/deque.rs
index e7ec86963ee..a88d13fda66 100644
--- a/src/libstd/deque.rs
+++ b/src/libstd/deque.rs
@@ -41,6 +41,7 @@ impl<T> Mutable for Deque<T> {
     }
 }
 
+#[cfg(stage0)]
 pub impl<T> Deque<T> {
     /// Create an empty Deque
     fn new() -> Deque<T> {
@@ -51,21 +52,142 @@ pub impl<T> Deque<T> {
     /// Return a reference to the first element in the deque
     ///
     /// Fails if the deque is empty
+    #[cfg(stage0)]
     fn peek_front(&self) -> &'self T { get(self.elts, self.lo) }
 
+    /// Return a reference to the first element in the deque
+    ///
+    /// Fails if the deque is empty
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn peek_front<'a>(&'a self) -> &'a T { get(self.elts, self.lo) }
+
     /// Return a reference to the last element in the deque
     ///
     /// Fails if the deque is empty
+    #[cfg(stage0)]
     fn peek_back(&self) -> &'self T { get(self.elts, self.hi - 1u) }
 
+    /// Return a reference to the last element in the deque
+    ///
+    /// Fails if the deque is empty
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn peek_back<'a>(&'a self) -> &'a T { get(self.elts, self.hi - 1u) }
+
     /// Retrieve an element in the deque by index
     ///
     /// Fails if there is no element with the given index
+    #[cfg(stage0)]
     fn get(&self, i: int) -> &'self T {
         let idx = (self.lo + (i as uint)) % self.elts.len();
         get(self.elts, idx)
     }
 
+    /// Retrieve an element in the deque by index
+    ///
+    /// Fails if there is no element with the given index
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn get<'a>(&'a self, i: int) -> &'a T {
+        let idx = (self.lo + (i as uint)) % self.elts.len();
+        get(self.elts, idx)
+    }
+
+    /// Iterate over the elements in the deque
+    fn each(&self, f: &fn(&T) -> bool) {
+        self.eachi(|_i, e| f(e))
+    }
+
+    /// Iterate over the elements in the deque by index
+    fn eachi(&self, f: &fn(uint, &T) -> bool) {
+        for uint::range(0, self.nelts) |i| {
+            if !f(i, self.get(i as int)) { return; }
+        }
+    }
+
+    /// Remove and return the first element in the deque
+    ///
+    /// Fails if the deque is empty
+    fn pop_front(&mut self) -> T {
+        let mut result = self.elts[self.lo].swap_unwrap();
+        self.lo = (self.lo + 1u) % self.elts.len();
+        self.nelts -= 1u;
+        result
+    }
+
+    /// Remove and return the last element in the deque
+    ///
+    /// Fails if the deque is empty
+    fn pop_back(&mut self) -> T {
+        if self.hi == 0u {
+            self.hi = self.elts.len() - 1u;
+        } else { self.hi -= 1u; }
+        let mut result = self.elts[self.hi].swap_unwrap();
+        self.elts[self.hi] = None;
+        self.nelts -= 1u;
+        result
+    }
+
+    /// Prepend an element to the deque
+    fn add_front(&mut self, t: T) {
+        let oldlo = self.lo;
+        if self.lo == 0u {
+            self.lo = self.elts.len() - 1u;
+        } else { self.lo -= 1u; }
+        if self.lo == self.hi {
+            self.elts = grow(self.nelts, oldlo, self.elts);
+            self.lo = self.elts.len() - 1u;
+            self.hi = self.nelts;
+        }
+        self.elts[self.lo] = Some(t);
+        self.nelts += 1u;
+    }
+
+    /// Append an element to the deque
+    fn add_back(&mut self, t: T) {
+        if self.lo == self.hi && self.nelts != 0u {
+            self.elts = grow(self.nelts, self.lo, self.elts);
+            self.lo = 0u;
+            self.hi = self.nelts;
+        }
+        self.elts[self.hi] = Some(t);
+        self.hi = (self.hi + 1u) % self.elts.len();
+        self.nelts += 1u;
+    }
+}
+
+#[cfg(stage1)]
+#[cfg(stage2)]
+#[cfg(stage3)]
+pub impl<T> Deque<T> {
+    /// Create an empty Deque
+    fn new() -> Deque<T> {
+        Deque{nelts: 0, lo: 0, hi: 0,
+              elts: vec::from_fn(initial_capacity, |_| None)}
+    }
+
+    /// Return a reference to the first element in the deque
+    ///
+    /// Fails if the deque is empty
+    fn peek_front<'a>(&'a self) -> &'a T { get(self.elts, self.lo) }
+
+    /// Return a reference to the last element in the deque
+    ///
+    /// Fails if the deque is empty
+    fn peek_back<'a>(&'a self) -> &'a T { get(self.elts, self.hi - 1u) }
+
+    /// Retrieve an element in the deque by index
+    ///
+    /// Fails if there is no element with the given index
+    fn get<'a>(&'a self, i: int) -> &'a T {
+        let idx = (self.lo + (i as uint)) % self.elts.len();
+        get(self.elts, idx)
+    }
+
     /// Iterate over the elements in the deque
     fn each(&self, f: &fn(&T) -> bool) {
         self.eachi(|_i, e| f(e))
diff --git a/src/libstd/future.rs b/src/libstd/future.rs
index a4887306d2a..feea8fb4fcd 100644
--- a/src/libstd/future.rs
+++ b/src/libstd/future.rs
@@ -55,7 +55,7 @@ pub impl<A:Copy> Future<A> {
 }
 
 pub impl<A> Future<A> {
-
+    #[cfg(stage0)]
     fn get_ref(&self) -> &'self A {
         /*!
         * Executes the future's closure and then returns a borrowed
@@ -80,6 +80,34 @@ pub impl<A> Future<A> {
             }
         }
     }
+
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn get_ref<'a>(&'a self) -> &'a A {
+        /*!
+        * Executes the future's closure and then returns a borrowed
+        * pointer to the result.  The borrowed pointer lasts as long as
+        * the future.
+        */
+        unsafe {
+            match self.state {
+                Forced(ref mut v) => { return cast::transmute(v); }
+                Evaluating => fail!(~"Recursive forcing of future!"),
+                Pending(_) => {}
+            }
+
+            let mut state = Evaluating;
+            self.state <-> state;
+            match state {
+                Forced(_) | Evaluating => fail!(~"Logic error."),
+                Pending(f) => {
+                    self.state = Forced(f());
+                    self.get_ref()
+                }
+            }
+        }
+    }
 }
 
 pub fn from_value<A>(val: A) -> Future<A> {
diff --git a/src/libstd/priority_queue.rs b/src/libstd/priority_queue.rs
index dd56e413595..c8d250f90f6 100644
--- a/src/libstd/priority_queue.rs
+++ b/src/libstd/priority_queue.rs
@@ -50,13 +50,29 @@ impl<T:Ord> Mutable for PriorityQueue<T> {
 
 pub impl <T:Ord> PriorityQueue<T> {
     /// Returns the greatest item in the queue - fails if empty
+    #[cfg(stage0)]
     fn top(&self) -> &'self T { &self.data[0] }
 
+    /// Returns the greatest item in the queue - fails if empty
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn top<'a>(&'a self) -> &'a T { &self.data[0] }
+
     /// Returns the greatest item in the queue - None if empty
+    #[cfg(stage0)]
     fn maybe_top(&self) -> Option<&'self T> {
         if self.is_empty() { None } else { Some(self.top()) }
     }
 
+    /// Returns the greatest item in the queue - None if empty
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn maybe_top<'a>(&'a self) -> Option<&'a T> {
+        if self.is_empty() { None } else { Some(self.top()) }
+    }
+
     /// Returns the number of elements the queue can hold without reallocating
     fn capacity(&self) -> uint { vec::capacity(&self.data) }
 
diff --git a/src/libstd/smallintmap.rs b/src/libstd/smallintmap.rs
index 811cd710a62..d50804ba47b 100644
--- a/src/libstd/smallintmap.rs
+++ b/src/libstd/smallintmap.rs
@@ -51,6 +51,7 @@ impl<V> Map<uint, V> for SmallIntMap<V> {
     }
 
     /// Visit all key-value pairs in order
+    #[cfg(stage0)]
     fn each(&self, it: &fn(&uint, &'self V) -> bool) {
         for uint::range(0, self.v.len()) |i| {
             match self.v[i] {
@@ -60,18 +61,40 @@ impl<V> Map<uint, V> for SmallIntMap<V> {
         }
     }
 
+    /// Visit all key-value pairs in order
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn each<'a>(&'a self, it: &fn(&uint, &'a V) -> bool) {
+        for uint::range(0, self.v.len()) |i| {
+            match self.v[i] {
+              Some(ref elt) => if !it(&i, elt) { break },
+              None => ()
+            }
+        }
+    }
+
     /// Visit all keys in order
     fn each_key(&self, blk: &fn(key: &uint) -> bool) {
         self.each(|k, _| blk(k))
     }
 
     /// Visit all values in order
+    #[cfg(stage0)]
     fn each_value(&self, blk: &fn(value: &V) -> bool) {
         self.each(|_, v| blk(v))
     }
 
+    /// Visit all values in order
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn each_value<'a>(&'a self, blk: &fn(value: &'a V) -> bool) {
+        self.each(|_, v| blk(v))
+    }
+
     /// Iterate over the map and mutate the contained values
-    fn mutate_values(&mut self, it: &fn(&uint, &'self mut V) -> bool) {
+    fn mutate_values(&mut self, it: &fn(&uint, &mut V) -> bool) {
         for uint::range(0, self.v.len()) |i| {
             match self.v[i] {
               Some(ref mut elt) => if !it(&i, elt) { break },
@@ -81,6 +104,7 @@ impl<V> Map<uint, V> for SmallIntMap<V> {
     }
 
     /// Return a reference to the value corresponding to the key
+    #[cfg(stage0)]
     fn find(&self, key: &uint) -> Option<&'self V> {
         if *key < self.v.len() {
             match self.v[*key] {
@@ -92,7 +116,23 @@ impl<V> Map<uint, V> for SmallIntMap<V> {
         }
     }
 
+    /// Return a reference to the value corresponding to the key
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn find<'a>(&'a self, key: &uint) -> Option<&'a V> {
+        if *key < self.v.len() {
+            match self.v[*key] {
+              Some(ref value) => Some(value),
+              None => None
+            }
+        } else {
+            None
+        }
+    }
+
     /// Return a mutable reference to the value corresponding to the key
+    #[cfg(stage0)]
     fn find_mut(&mut self, key: &uint) -> Option<&'self mut V> {
         if *key < self.v.len() {
             match self.v[*key] {
@@ -104,6 +144,21 @@ impl<V> Map<uint, V> for SmallIntMap<V> {
         }
     }
 
+    /// Return a mutable reference to the value corresponding to the key
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn find_mut<'a>(&'a mut self, key: &uint) -> Option<&'a mut V> {
+        if *key < self.v.len() {
+            match self.v[*key] {
+              Some(ref mut value) => Some(value),
+              None => None
+            }
+        } else {
+            None
+        }
+    }
+
     /// Insert a key-value pair into the map. An existing value for a
     /// key is replaced by the new value. Return true if the key did
     /// not already exist in the map.
@@ -134,6 +189,7 @@ pub impl<V> SmallIntMap<V> {
     fn new() -> SmallIntMap<V> { SmallIntMap{v: ~[]} }
 
     /// Visit all key-value pairs in reverse order
+    #[cfg(stage0)]
     fn each_reverse(&self, it: &fn(uint, &'self V) -> bool) {
         for uint::range_rev(self.v.len(), 0) |i| {
             match self.v[i - 1] {
@@ -143,9 +199,30 @@ pub impl<V> SmallIntMap<V> {
         }
     }
 
+    /// Visit all key-value pairs in reverse order
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn each_reverse<'a>(&'a self, it: &fn(uint, &'a V) -> bool) {
+        for uint::range_rev(self.v.len(), 0) |i| {
+            match self.v[i - 1] {
+              Some(ref elt) => if !it(i - 1, elt) { break },
+              None => ()
+            }
+        }
+    }
+
+    #[cfg(stage0)]
     fn get(&self, key: &uint) -> &'self V {
         self.find(key).expect("key not present")
     }
+
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn get<'a>(&'a self, key: &uint) -> &'a V {
+        self.find(key).expect("key not present")
+    }
 }
 
 pub impl<V:Copy> SmallIntMap<V> {
diff --git a/src/libstd/treemap.rs b/src/libstd/treemap.rs
index 041ea855cb3..006455c44e4 100644
--- a/src/libstd/treemap.rs
+++ b/src/libstd/treemap.rs
@@ -105,26 +105,45 @@ impl<K: TotalOrd, V> Map<K, V> for TreeMap<K, V> {
     }
 
     /// Visit all key-value pairs in order
+    #[cfg(stage0)]
     fn each(&self, f: &fn(&'self K, &'self V) -> bool) {
         each(&self.root, f)
     }
 
+    /// Visit all key-value pairs in order
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn each<'a>(&'a self, f: &fn(&'a K, &'a V) -> bool) {
+        each(&self.root, f)
+    }
+
     /// Visit all keys in order
     fn each_key(&self, f: &fn(&K) -> bool) {
         self.each(|k, _| f(k))
     }
 
     /// Visit all values in order
+    #[cfg(stage0)]
     fn each_value(&self, f: &fn(&V) -> bool) {
         self.each(|_, v| f(v))
     }
 
+    /// Visit all values in order
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn each_value<'a>(&'a self, f: &fn(&'a V) -> bool) {
+        self.each(|_, v| f(v))
+    }
+
     /// Iterate over the map and mutate the contained values
-    fn mutate_values(&mut self, f: &fn(&'self K, &'self mut V) -> bool) {
+    fn mutate_values(&mut self, f: &fn(&K, &mut V) -> bool) {
         mutate_values(&mut self.root, f);
     }
 
     /// Return a reference to the value corresponding to the key
+    #[cfg(stage0)]
     fn find(&self, key: &K) -> Option<&'self V> {
         let mut current: &'self Option<~TreeNode<K, V>> = &self.root;
         loop {
@@ -141,12 +160,42 @@ impl<K: TotalOrd, V> Map<K, V> for TreeMap<K, V> {
         }
     }
 
+    /// Return a reference to the value corresponding to the key
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn find<'a>(&'a self, key: &K) -> Option<&'a V> {
+        let mut current: &'a Option<~TreeNode<K, V>> = &self.root;
+        loop {
+            match *current {
+              Some(ref r) => {
+                match key.cmp(&r.key) {
+                  Less => current = &r.left,
+                  Greater => current = &r.right,
+                  Equal => return Some(&r.value)
+                }
+              }
+              None => return None
+            }
+        }
+    }
+
     /// Return a mutable reference to the value corresponding to the key
     #[inline(always)]
+    #[cfg(stage0)]
     fn find_mut(&mut self, key: &K) -> Option<&'self mut V> {
         find_mut(&mut self.root, key)
     }
 
+    /// Return a mutable reference to the value corresponding to the key
+    #[inline(always)]
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn find_mut<'a>(&'a mut self, key: &K) -> Option<&'a mut V> {
+        find_mut(&mut self.root, key)
+    }
+
     /// Insert a key-value pair into the map. An existing value for a
     /// key is replaced by the new value. Return true if the key did
     /// not already exist in the map.
@@ -170,7 +219,16 @@ pub impl<K: TotalOrd, V> TreeMap<K, V> {
     fn new() -> TreeMap<K, V> { TreeMap{root: None, length: 0} }
 
     /// Visit all key-value pairs in reverse order
-    fn each_reverse(&'self self, f: &fn(&'self K, &'self V) -> bool) {
+    #[cfg(stage0)]
+    fn each_reverse(&self, f: &fn(&'self K, &'self V) -> bool) {
+        each_reverse(&self.root, f);
+    }
+
+    /// Visit all key-value pairs in reverse order
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn each_reverse<'a>(&'a self, f: &fn(&'a K, &'a V) -> bool) {
         each_reverse(&self.root, f);
     }
 
@@ -186,9 +244,19 @@ pub impl<K: TotalOrd, V> TreeMap<K, V> {
 
     /// Get a lazy iterator over the key-value pairs in the map.
     /// Requires that it be frozen (immutable).
+    #[cfg(stage0)]
     fn iter(&self) -> TreeMapIterator<'self, K, V> {
         TreeMapIterator{stack: ~[], node: &self.root}
     }
+
+    /// Get a lazy iterator over the key-value pairs in the map.
+    /// Requires that it be frozen (immutable).
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn iter<'a>(&'a self) -> TreeMapIterator<'a, K, V> {
+        TreeMapIterator{stack: ~[], node: &self.root}
+    }
 }
 
 /// Lazy forward iterator over a map
@@ -490,9 +558,20 @@ pub impl <T: TotalOrd> TreeSet<T> {
     /// Get a lazy iterator over the values in the set.
     /// Requires that it be frozen (immutable).
     #[inline(always)]
+    #[cfg(stage0)]
     fn iter(&self) -> TreeSetIterator<'self, T> {
         TreeSetIterator{iter: self.map.iter()}
     }
+
+    /// Get a lazy iterator over the values in the set.
+    /// Requires that it be frozen (immutable).
+    #[inline(always)]
+    #[cfg(stage1)]
+    #[cfg(stage2)]
+    #[cfg(stage3)]
+    fn iter<'a>(&'a self) -> TreeSetIterator<'a, T> {
+        TreeSetIterator{iter: self.map.iter()}
+    }
 }
 
 /// Lazy forward iterator over a set