auto merge of rust-lang#4815 : thestinger/rust/treemap, r=pcwalton

5283a8b reworks the TreeMap lazy iterator to use `&mut` again, which closes rust-lang#4763. It gets the performance of the set methods back in the same ballpark that it was pre-INHTWAMA which is nice. These can be turned back into methods eventually. e5b6334 removes the transitional smallintmap attributes which closes rust-lang#4737.

Author: bors

src/libcore/hashmap.rs

@@ -49,9 +49,8 @@ pub mod linear {
  buckets: ~[Option<Bucket<K, V>>],
  }
 
- // FIXME(#3148) -- we could rewrite FoundEntry
- // to have type Option<&Bucket<K, V>> which would be nifty
- // However, that won't work until #3148 is fixed
+ // We could rewrite FoundEntry to have type Option<&Bucket<K, V>>
+ // which would be nifty
  enum SearchResult {
  FoundEntry(uint), FoundHole(uint), TableFull
  }
@@ -296,8 +295,6 @@ pub mod linear {
  FoundEntry(idx) => {
  match self.buckets[idx] {
  Some(ref bkt) => {
- // FIXME(#3148)---should be inferred
- let bkt: &self/Bucket<K, V> = bkt;
  Some(&bkt.value)
  }
  None => {

src/libstd/json.rs

@@ -856,9 +856,6 @@ pub impl Decoder: serialize::Decoder {
  debug!("read_vec_elt(idx=%u)", idx);
  match *self.peek() {
  List(ref list) => {
- // FIXME(#3148)---should be inferred
- let list: &self/~[Json] = list;
-
  self.stack.push(&list[idx]);
  f()
  }
@@ -885,9 +882,6 @@ pub impl Decoder: serialize::Decoder {
  let top = self.peek();
  match *top {
  Object(ref obj) => {
- // FIXME(#3148) This hint should not be necessary.
- let obj: &self/~Object = obj;
-
  match obj.find(&name.to_owned()) {
  None => die!(fmt!("no such field: %s", name)),
  Some(json) => {
@@ -917,8 +911,6 @@ pub impl Decoder: serialize::Decoder {
  debug!("read_tup_elt(idx=%u)", idx);
  match *self.peek() {
  List(ref list) => {
- // FIXME(#3148)---should be inferred
- let list: &self/~[Json] = list;
  self.stack.push(&list[idx]);
  f()
  }

src/libstd/smallintmap.rs

@@ -116,8 +116,6 @@ pub impl<V> SmallIntMap<V> {
 }
 
 pub impl<V: Copy> SmallIntMap<V> {
- // FIXME: #4733, remove after the next snapshot
- #[cfg(stage2)]
  fn update_with_key(&mut self, key: uint, val: V,
  ff: fn(uint, V, V) -> V) -> bool {
  match self.find(&key) {
@@ -126,8 +124,6 @@ pub impl<V: Copy> SmallIntMap<V> {
  }
  }
 
- // FIXME: #4733, remove after the next snapshot
- #[cfg(stage2)]
  fn update(&mut self, key: uint, newval: V, ff: fn(V, V) -> V) -> bool {
  self.update_with_key(key, newval, |_k, v, v1| ff(v,v1))
  }