auto merge of #5796 : nikomatsakis/rust/issue-5656-fix-map-iteration, r=nikomatsakis

Revert map.each to something which takes two parameters rather than a tuple.  The current setup iterates over `BaseIter<(&'self K, &'self V)>` where 'self is a lifetime declared *in the `each()` method*.  You can't place such a type in the impl declaration.  The compiler currently allows it, but this will not be legal under #5656 and I'm pretty sure it's not sound now.  It's too bad that maps can't implement `BaseIter` (at least not over a tuple as they do here) but I think it has to be this way for the time being.

r? @thestinger

19 files changed, 132 insertions, 158 deletions

diff --git a/src/libcore/container.rs b/src/libcore/container.rs
index e20821b919b..a1836d16fd7 100644
--- a/src/libcore/container.rs
+++ b/src/libcore/container.rs
@@ -29,6 +29,9 @@ pub trait Map<K, V>: Mutable {
     /// Return true if the map contains a value for the specified key
     fn contains_key(&self, key: &K) -> bool;
 
+    // Visits all keys and values
+    fn each(&self, f: &fn(&K, &V) -> bool);
+
     /// Visit all keys
     fn each_key(&self, f: &fn(&K) -> bool);
 
diff --git a/src/libcore/hashmap.rs b/src/libcore/hashmap.rs
index 5dbf085f097..d4af0ffe7fe 100644
--- a/src/libcore/hashmap.rs
+++ b/src/libcore/hashmap.rs
@@ -279,24 +279,6 @@ priv impl<K:Hash + IterBytes + Eq,V> HashMap<K, V> {
     }
 }
 
-impl<'self,K:Hash + IterBytes + Eq,V>
-        BaseIter<(&'self K, &'self V)> for HashMap<K, V> {
-    /// Visit all key-value pairs
-    fn each(&self, blk: &fn(&(&'self K, &'self V)) -> bool) {
-        for uint::range(0, self.buckets.len()) |i| {
-            let mut broke = false;
-            do self.buckets[i].map |bucket| {
-                if !blk(&(&bucket.key, &bucket.value)) {
-                    broke = true; // FIXME(#3064) just write "break;"
-                }
-            };
-            if broke { break; }
-        }
-    }
-    fn size_hint(&self) -> Option<uint> { Some(self.len()) }
-}
-
-
 impl<K:Hash + IterBytes + Eq,V> Container for HashMap<K, V> {
     /// Return the number of elements in the map
     fn len(&const self) -> uint { self.size }
@@ -315,7 +297,7 @@ impl<K:Hash + IterBytes + Eq,V> Mutable for HashMap<K, V> {
     }
 }
 
-impl<'self,K:Hash + IterBytes + Eq,V> Map<K, V> for HashMap<K, V> {
+impl<K:Hash + IterBytes + Eq,V> Map<K, V> for HashMap<K, V> {
     /// Return true if the map contains a value for the specified key
     fn contains_key(&self, k: &K) -> bool {
         match self.bucket_for_key(k) {
@@ -324,14 +306,25 @@ impl<'self,K:Hash + IterBytes + Eq,V> Map<K, V> for HashMap<K, V> {
         }
     }
 
+    /// Visit all key-value pairs
+    fn each(&self, blk: &fn(&'self K, &'self V) -> bool) {
+        for uint::range(0, self.buckets.len()) |i| {
+            for self.buckets[i].each |bucket| {
+                if !blk(&bucket.key, &bucket.value) {
+                    return;
+                }
+            }
+        }
+    }
+
     /// Visit all keys
     fn each_key(&self, blk: &fn(k: &K) -> bool) {
-        self.each(|&(k, _)| blk(k))
+        self.each(|k, _| blk(k))
     }
 
     /// Visit all values
     fn each_value(&self, blk: &fn(v: &V) -> bool) {
-        self.each(|&(_, v)| blk(v))
+        self.each(|_, v| blk(v))
     }
 
     /// Iterate over the map and mutate the contained values
@@ -545,7 +538,7 @@ impl<K:Hash + IterBytes + Eq,V:Eq> Eq for HashMap<K, V> {
     fn eq(&self, other: &HashMap<K, V>) -> bool {
         if self.len() != other.len() { return false; }
 
-        for self.each |&(key, value)| {
+        for self.each |key, value| {
             match other.find(key) {
                 None => return false,
                 Some(v) => if value != v { return false },
@@ -798,7 +791,7 @@ mod test_map {
             assert!(m.insert(i, i*2));
         }
         let mut observed = 0;
-        for m.each |&(k, v)| {
+        for m.each |k, v| {
             assert!(*v == *k * 2);
             observed |= (1 << *k);
         }
diff --git a/src/libcore/trie.rs b/src/libcore/trie.rs
index 5d87e2a296d..f6a92a21385 100644
--- a/src/libcore/trie.rs
+++ b/src/libcore/trie.rs
@@ -28,24 +28,6 @@ pub struct TrieMap<T> {
     priv length: uint
 }
 
-impl<'self,T> BaseIter<(uint, &'self T)> for TrieMap<T> {
-    /// Visit all key-value pairs in order
-    #[inline(always)]
-    fn each(&self, f: &fn(&(uint, &'self T)) -> bool) {
-        self.root.each(f);
-    }
-    #[inline(always)]
-    fn size_hint(&self) -> Option<uint> { Some(self.len()) }
-}
-
-impl<'self,T> ReverseIter<(uint, &'self T)> for TrieMap<T> {
-    /// Visit all key-value pairs in reverse order
-    #[inline(always)]
-    fn each_reverse(&self, f: &fn(&(uint, &'self T)) -> bool) {
-        self.root.each_reverse(f);
-    }
-}
-
 impl<T> Container for TrieMap<T> {
     /// Return the number of elements in the map
     #[inline(always)]
@@ -72,16 +54,22 @@ impl<T> Map<uint, T> for TrieMap<T> {
         self.find(key).is_some()
     }
 
+    /// Visit all key-value pairs in order
+    #[inline(always)]
+    fn each(&self, f: &fn(&uint, &'self T) -> bool) {
+        self.root.each(f);
+    }
+
     /// Visit all keys in order
     #[inline(always)]
     fn each_key(&self, f: &fn(&uint) -> bool) {
-        self.each(|&(k, _)| f(&k))
+        self.each(|k, _| f(k))
     }
 
     /// Visit all values in order
     #[inline(always)]
     fn each_value(&self, f: &fn(&T) -> bool) {
-        self.each(|&(_, v)| f(v))
+        self.each(|_, v| f(v))
     }
 
     /// Iterate over the map and mutate the contained values
@@ -148,16 +136,22 @@ pub impl<T> TrieMap<T> {
         TrieMap{root: TrieNode::new(), length: 0}
     }
 
+    /// Visit all key-value pairs in reverse order
+    #[inline(always)]
+    fn each_reverse(&self, f: &fn(&uint, &'self T) -> bool) {
+        self.root.each_reverse(f);
+    }
+
     /// Visit all keys in reverse order
     #[inline(always)]
     fn each_key_reverse(&self, f: &fn(&uint) -> bool) {
-        self.each_reverse(|&(k, _)| f(&k))
+        self.each_reverse(|k, _| f(k))
     }
 
     /// Visit all values in reverse order
     #[inline(always)]
     fn each_value_reverse(&self, f: &fn(&T) -> bool) {
-        self.each_reverse(|&(_, v)| f(v))
+        self.each_reverse(|_, v| f(v))
     }
 }
 
@@ -239,22 +233,22 @@ impl<T> TrieNode<T> {
 }
 
 impl<T> TrieNode<T> {
-    fn each(&self, f: &fn(&(uint, &'self T)) -> bool) -> bool {
+    fn each(&self, f: &fn(&uint, &'self T) -> bool) -> bool {
         for uint::range(0, self.children.len()) |idx| {
             match self.children[idx] {
                 Internal(ref x) => if !x.each(f) { return false },
-                External(k, ref v) => if !f(&(k, v)) { return false },
+                External(k, ref v) => if !f(&k, v) { return false },
                 Nothing => ()
             }
         }
         true
     }
 
-    fn each_reverse(&self, f: &fn(&(uint, &'self T)) -> bool) -> bool {
+    fn each_reverse(&self, f: &fn(&uint, &'self T) -> bool) -> bool {
         for uint::range_rev(self.children.len(), 0) |idx| {
             match self.children[idx - 1] {
                 Internal(ref x) => if !x.each_reverse(f) { return false },
-                External(k, ref v) => if !f(&(k, v)) { return false },
+                External(k, ref v) => if !f(&k, v) { return false },
                 Nothing => ()
             }
         }
@@ -438,8 +432,8 @@ mod tests {
         assert!(m.insert(1, 2));
 
         let mut n = 0;
-        for m.each |&(k, v)| {
-            assert!(k == n);
+        for m.each |k, v| {
+            assert!(*k == n);
             assert!(*v == n * 2);
             n += 1;
         }
@@ -454,11 +448,11 @@ mod tests {
         }
 
         let mut n = uint::max_value - 9999;
-        for m.each |&(k, v)| {
+        for m.each |k, v| {
             if n == uint::max_value - 5000 { break }
             assert!(n < uint::max_value - 5000);
 
-            assert!(k == n);
+            assert!(*k == n);
             assert!(*v == n / 2);
             n += 1;
         }
@@ -475,8 +469,8 @@ mod tests {
         assert!(m.insert(1, 2));
 
         let mut n = 4;
-        for m.each_reverse |&(k, v)| {
-            assert!(k == n);
+        for m.each_reverse |k, v| {
+            assert!(*k == n);
             assert!(*v == n * 2);
             n -= 1;
         }
@@ -491,11 +485,11 @@ mod tests {
         }
 
         let mut n = uint::max_value;
-        for m.each_reverse |&(k, v)| {
+        for m.each_reverse |k, v| {
             if n == uint::max_value - 5000 { break }
             assert!(n > uint::max_value - 5000);
 
-            assert!(k == n);
+            assert!(*k == n);
             assert!(*v == n / 2);
             n -= 1;
         }
diff --git a/src/librustc/metadata/cstore.rs b/src/librustc/metadata/cstore.rs
index 65bd37236b7..d738c3e7747 100644
--- a/src/librustc/metadata/cstore.rs
+++ b/src/librustc/metadata/cstore.rs
@@ -86,7 +86,7 @@ pub fn have_crate_data(cstore: &CStore, cnum: ast::crate_num) -> bool {
 
 pub fn iter_crate_data(cstore: &CStore,
                        i: &fn(ast::crate_num, @crate_metadata)) {
-    for cstore.metas.each |&(&k, &v)| {
+    for cstore.metas.each |&k, &v| {
         i(k, v);
     }
 }
diff --git a/src/librustc/middle/lang_items.rs b/src/librustc/middle/lang_items.rs
index ab9b8ca0db6..0dd28e5ca7c 100644
--- a/src/librustc/middle/lang_items.rs
+++ b/src/librustc/middle/lang_items.rs
@@ -397,7 +397,7 @@ pub impl<'self> LanguageItemCollector<'self> {
     }
 
     fn check_completeness(&self) {
-        for self.item_refs.each |&(&key, &item_ref)| {
+        for self.item_refs.each |&key, &item_ref| {
             match self.items.items[item_ref] {
                 None => {
                     self.session.err(fmt!("no item found for `%s`", *key));
diff --git a/src/librustc/middle/lint.rs b/src/librustc/middle/lint.rs
index 0adf4b87f3a..6f8992bf1ca 100644
--- a/src/librustc/middle/lint.rs
+++ b/src/librustc/middle/lint.rs
@@ -460,7 +460,7 @@ pub fn build_settings_crate(sess: session::Session, crate: @ast::crate) {
 
     do cx.with_lint_attrs(/*bad*/copy crate.node.attrs) |cx| {
         // Copy out the default settings
-        for cx.curr.each |&(k, &v)| {
+        for cx.curr.each |&k, &v| {
             sess.lint_settings.default_settings.insert(k, v);
         }
 
diff --git a/src/librustc/middle/region.rs b/src/librustc/middle/region.rs
index 1c60c37ed12..50c193ab3b0 100644
--- a/src/librustc/middle/region.rs
+++ b/src/librustc/middle/region.rs
@@ -842,7 +842,7 @@ pub fn determine_rp_in_crate(sess: Session,
     debug!("%s", {
         debug!("Region variance results:");
         let region_paramd_items = cx.region_paramd_items;
-        for region_paramd_items.each |&(&key, &value)| {
+        for region_paramd_items.each |&key, &value| {
             debug!("item %? (%s) is parameterized with variance %?",
                    key,
                    ast_map::node_id_to_str(ast_map, key,
diff --git a/src/librustc/middle/resolve.rs b/src/librustc/middle/resolve.rs
index fcf0b7022a7..c7f53c744f1 100644
--- a/src/librustc/middle/resolve.rs
+++ b/src/librustc/middle/resolve.rs
@@ -2369,7 +2369,7 @@ pub impl Resolver {
 
         // Add all resolved imports from the containing module.
         for containing_module.import_resolutions.each
-                |&(ident, target_import_resolution)| {
+                |ident, target_import_resolution| {
 
             debug!("(resolving glob import) writing module resolution \
                     %? into `%s`",
@@ -2457,13 +2457,13 @@ pub impl Resolver {
         };
 
         // Add all children from the containing module.
-        for containing_module.children.each |&(ident, name_bindings)| {
+        for containing_module.children.each |ident, name_bindings| {
             merge_import_resolution(ident, *name_bindings);
         }
 
         // Add external module children from the containing module.
         for containing_module.external_module_children.each
-                |&(ident, module)| {
+                |ident, module| {
             let name_bindings =
                 @mut Resolver::create_name_bindings_from_module(*module);
             merge_import_resolution(ident, name_bindings);
@@ -3111,7 +3111,7 @@ pub impl Resolver {
     fn add_exports_for_module(@mut self,
                               exports2: &mut ~[Export2],
                               module_: @mut Module) {
-        for module_.children.each |&(ident, namebindings)| {
+        for module_.children.each |ident, namebindings| {
             debug!("(computing exports) maybe export '%s'",
                    *self.session.str_of(*ident));
             self.add_exports_of_namebindings(&mut *exports2,
@@ -3126,7 +3126,7 @@ pub impl Resolver {
                                              false);
         }
 
-        for module_.import_resolutions.each |&(ident, importresolution)| {
+        for module_.import_resolutions.each |ident, importresolution| {
             if importresolution.privacy != Public {
                 debug!("(computing exports) not reexporting private `%s`",
                        *self.session.str_of(*ident));
@@ -3934,7 +3934,7 @@ pub impl Resolver {
         for arm.pats.eachi() |i, p| {
             let map_i = self.binding_mode_map(*p);
 
-            for map_0.each |&(&key, &binding_0)| {
+            for map_0.each |&key, &binding_0| {
                 match map_i.find(&key) {
                   None => {
                     self.session.span_err(
@@ -3955,7 +3955,7 @@ pub impl Resolver {
                 }
             }
 
-            for map_i.each |&(&key, &binding)| {
+            for map_i.each |&key, &binding| {
                 if !map_0.contains_key(&key) {
                     self.session.span_err(
                         binding.span,
@@ -5248,7 +5248,7 @@ pub impl Resolver {
         }
 
         debug!("Import resolutions:");
-        for module_.import_resolutions.each |&(name, import_resolution)| {
+        for module_.import_resolutions.each |name, import_resolution| {
             let mut value_repr;
             match import_resolution.target_for_namespace(ValueNS) {
                 None => { value_repr = ~""; }
diff --git a/src/librustc/middle/trans/base.rs b/src/librustc/middle/trans/base.rs
index d94f2bf3c2f..4faff086098 100644
--- a/src/librustc/middle/trans/base.rs
+++ b/src/librustc/middle/trans/base.rs
@@ -2848,7 +2848,7 @@ pub fn create_module_map(ccx: @CrateContext) -> ValueRef {
         lib::llvm::SetLinkage(map, lib::llvm::InternalLinkage);
     }
     let mut elts: ~[ValueRef] = ~[];
-    for ccx.module_data.each |&(key, &val)| {
+    for ccx.module_data.each |key, &val| {
         let elt = C_struct(~[p2i(ccx, C_cstr(ccx, @/*bad*/ copy *key)),
                             p2i(ccx, val)]);
         elts.push(elt);
@@ -3139,7 +3139,7 @@ pub fn trans_crate(sess: session::Session,
         }
 
         if ccx.sess.count_llvm_insns() {
-            for ccx.stats.llvm_insns.each |&(&k, &v)| {
+            for ccx.stats.llvm_insns.each |&k, &v| {
                 io::println(fmt!("%-7u %s", v, k));
             }
         }
diff --git a/src/librustc/middle/typeck/infer/region_inference.rs b/src/librustc/middle/typeck/infer/region_inference.rs
index 98d12bea6a4..e6354d4ab88 100644
--- a/src/librustc/middle/typeck/infer/region_inference.rs
+++ b/src/librustc/middle/typeck/infer/region_inference.rs
@@ -1223,7 +1223,7 @@ pub impl RegionVarBindings {
 
         // It would be nice to write this using map():
         let mut edges = vec::with_capacity(num_edges);
-        for self.constraints.each |&(constraint, span)| {
+        for self.constraints.each |constraint, span| {
             edges.push(GraphEdge {
                 next_edge: [uint::max_value, uint::max_value],
                 constraint: *constraint,
diff --git a/src/librustc/rustc.rc b/src/librustc/rustc.rc
index 94fcb85d1d8..642a94b1945 100644
--- a/src/librustc/rustc.rc
+++ b/src/librustc/rustc.rc
@@ -177,7 +177,7 @@ Available lint options:
                      padded(max_key, ~"name"), ~"default", ~"meaning"));
     io::println(fmt!("    %s  %7.7s  %s\n",
                      padded(max_key, ~"----"), ~"-------", ~"-------"));
-    for lint_dict.each |&(k, v)| {
+    for lint_dict.each |k, v| {
         let k = str::replace(*k, ~"_", ~"-");
         io::println(fmt!("    %s  %7.7s  %s",
                          padded(max_key, k),
diff --git a/src/libstd/json.rs b/src/libstd/json.rs
index d733a60f34f..90a745aaeb9 100644
--- a/src/libstd/json.rs
+++ b/src/libstd/json.rs
@@ -926,7 +926,7 @@ impl Eq for Json {
                     &Object(ref d1) => {
                         if d0.len() == d1.len() {
                             let mut equal = true;
-                            for d0.each |&(k, v0)| {
+                            for d0.each |k, v0| {
                                 match d1.find(k) {
                                     Some(v1) if v0 == v1 => { },
                                     _ => { equal = false; break }
@@ -989,12 +989,12 @@ impl Ord for Json {
                         let mut d1_flat = ~[];
 
                         // FIXME #4430: this is horribly inefficient...
-                        for d0.each |&(k, v)| {
+                        for d0.each |k, v| {
                              d0_flat.push((@copy *k, @copy *v));
                         }
                         d0_flat.qsort();
 
-                        for d1.each |&(k, v)| {
+                        for d1.each |k, v| {
                             d1_flat.push((@copy *k, @copy *v));
                         }
                         d1_flat.qsort();
@@ -1125,7 +1125,7 @@ impl<A:ToJson> ToJson for ~[A] {
 impl<A:ToJson + Copy> ToJson for HashMap<~str, A> {
     fn to_json(&self) -> Json {
         let mut d = HashMap::new();
-        for self.each |&(key, value)| {
+        for self.each |key, value| {
             d.insert(copy *key, value.to_json());
         }
         Object(~d)
diff --git a/src/libstd/net_url.rs b/src/libstd/net_url.rs
index f7ffa7435cf..b8e0d9d9b2a 100644
--- a/src/libstd/net_url.rs
+++ b/src/libstd/net_url.rs
@@ -216,7 +216,7 @@ pub fn encode_form_urlencoded(m: &HashMap<~str, ~[~str]>) -> ~str {
     let mut out = ~"";
     let mut first = true;
 
-    for m.each |&(key, values)| {
+    for m.each |key, values| {
         let key = encode_plus(*key);
 
         for values.each |value| {
diff --git a/src/libstd/serialize.rs b/src/libstd/serialize.rs
index e1ab59fb2b3..c2f0d9cb43f 100644
--- a/src/libstd/serialize.rs
+++ b/src/libstd/serialize.rs
@@ -595,7 +595,7 @@ impl<
     fn encode(&self, e: &E) {
         do e.emit_map(self.len()) {
             let mut i = 0;
-            for self.each |&(key, val)| {
+            for self.each |key, val| {
                 e.emit_map_elt_key(i, || key.encode(e));
                 e.emit_map_elt_val(i, || val.encode(e));
                 i += 1;
@@ -659,7 +659,7 @@ impl<
     fn encode(&self, e: &E) {
         do e.emit_map(self.len()) {
             let mut i = 0;
-            for self.each |&(key, val)| {
+            for self.each |key, val| {
                 e.emit_map_elt_key(i, || key.encode(e));
                 e.emit_map_elt_val(i, || val.encode(e));
                 i += 1;
@@ -717,7 +717,7 @@ impl<
     fn encode(&self, e: &E) {
         do e.emit_map(self.len()) {
             let mut i = 0;
-            for self.each |&(key, val)| {
+            for self.each |key, val| {
                 e.emit_map_elt_key(i, || key.encode(e));
                 e.emit_map_elt_val(i, || val.encode(e));
                 i += 1;
diff --git a/src/libstd/smallintmap.rs b/src/libstd/smallintmap.rs
index b6c5ec03068..811cd710a62 100644
--- a/src/libstd/smallintmap.rs
+++ b/src/libstd/smallintmap.rs
@@ -14,7 +14,7 @@
  */
 
 use core::container::{Container, Mutable, Map, Set};
-use core::iter::{BaseIter, ReverseIter};
+use core::iter::{BaseIter};
 use core::option::{Some, None};
 use core::prelude::*;
 
@@ -22,32 +22,6 @@ pub struct SmallIntMap<T> {
     priv v: ~[Option<T>],
 }
 
-impl<'self, V> BaseIter<(uint, &'self V)> for SmallIntMap<V> {
-    /// Visit all key-value pairs in order
-    fn each(&self, it: &fn(&(uint, &'self V)) -> bool) {
-        for uint::range(0, self.v.len()) |i| {
-            match self.v[i] {
-              Some(ref elt) => if !it(&(i, elt)) { break },
-              None => ()
-            }
-        }
-    }
-
-    fn size_hint(&self) -> Option<uint> { Some(self.len()) }
-}
-
-impl<'self, V> ReverseIter<(uint, &'self V)> for SmallIntMap<V> {
-    /// Visit all key-value pairs in reverse order
-    fn each_reverse(&self, it: &fn(&(uint, &'self 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 => ()
-            }
-        }
-    }
-}
-
 impl<V> Container for SmallIntMap<V> {
     /// Return the number of elements in the map
     fn len(&const self) -> uint {
@@ -76,14 +50,24 @@ impl<V> Map<uint, V> for SmallIntMap<V> {
         self.find(key).is_some()
     }
 
+    /// Visit all key-value pairs in order
+    fn each(&self, it: &fn(&uint, &'self 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))
+        self.each(|k, _| blk(k))
     }
 
     /// Visit all values in order
     fn each_value(&self, blk: &fn(value: &V) -> bool) {
-        self.each(|&(_, v)| blk(v))
+        self.each(|_, v| blk(v))
     }
 
     /// Iterate over the map and mutate the contained values
@@ -149,6 +133,16 @@ pub impl<V> SmallIntMap<V> {
     /// Create an empty SmallIntMap
     fn new() -> SmallIntMap<V> { SmallIntMap{v: ~[]} }
 
+    /// Visit all key-value pairs in reverse order
+    fn each_reverse(&self, it: &fn(uint, &'self 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 => ()
+            }
+        }
+    }
+
     fn get(&self, key: &uint) -> &'self V {
         self.find(key).expect("key not present")
     }
diff --git a/src/libstd/treemap.rs b/src/libstd/treemap.rs
index d0868da4408..041ea855cb3 100644
--- a/src/libstd/treemap.rs
+++ b/src/libstd/treemap.rs
@@ -82,24 +82,6 @@ impl<K: Ord + TotalOrd, V> Ord for TreeMap<K, V> {
     fn gt(&self, other: &TreeMap<K, V>) -> bool { lt(other, self) }
 }
 
-impl<'self, K: TotalOrd, V> BaseIter<(&'self K, &'self V)> for TreeMap<K, V> {
-    /// Visit all key-value pairs in order
-    fn each(&self, f: &fn(&(&'self K, &'self V)) -> bool) {
-        each(&self.root, f)
-    }
-    fn size_hint(&self) -> Option<uint> { Some(self.len()) }
-}
-
-impl<'self, K: TotalOrd, V>
-    ReverseIter<(&'self K, &'self V)>
-    for TreeMap<K, V>
-{
-    /// Visit all key-value pairs in reverse order
-    fn each_reverse(&self, f: &fn(&(&'self K, &'self V)) -> bool) {
-        each_reverse(&self.root, f);
-    }
-}
-
 impl<K: TotalOrd, V> Container for TreeMap<K, V> {
     /// Return the number of elements in the map
     fn len(&const self) -> uint { self.length }
@@ -122,12 +104,19 @@ impl<K: TotalOrd, V> Map<K, V> for TreeMap<K, V> {
         self.find(key).is_some()
     }
 
+    /// Visit all key-value pairs in order
+    fn each(&self, f: &fn(&'self K, &'self V) -> bool) {
+        each(&self.root, f)
+    }
+
     /// Visit all keys in order
-    fn each_key(&self, f: &fn(&K) -> bool) { self.each(|&(k, _)| f(k)) }
+    fn each_key(&self, f: &fn(&K) -> bool) {
+        self.each(|k, _| f(k))
+    }
 
     /// Visit all values in order
     fn each_value(&self, f: &fn(&V) -> bool) {
-        self.each(|&(_, v)| f(v))
+        self.each(|_, v| f(v))
     }
 
     /// Iterate over the map and mutate the contained values
@@ -180,14 +169,19 @@ pub impl<K: TotalOrd, V> TreeMap<K, V> {
     /// Create an empty TreeMap
     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) {
+        each_reverse(&self.root, f);
+    }
+
     /// Visit all keys in reverse order
     fn each_key_reverse(&self, f: &fn(&K) -> bool) {
-        self.each_reverse(|&(k, _)| f(k))
+        self.each_reverse(|k, _| f(k))
     }
 
     /// Visit all values in reverse order
     fn each_value_reverse(&self, f: &fn(&V) -> bool) {
-        self.each_reverse(|&(_, v)| f(v))
+        self.each_reverse(|_, v| f(v))
     }
 
     /// Get a lazy iterator over the key-value pairs in the map.
@@ -538,18 +532,18 @@ pub impl<K: TotalOrd, V> TreeNode<K, V> {
 }
 
 fn each<'r, K: TotalOrd, V>(node: &'r Option<~TreeNode<K, V>>,
-                            f: &fn(&(&'r K, &'r V)) -> bool) {
+                            f: &fn(&'r K, &'r V) -> bool) {
     for node.each |x| {
         each(&x.left, f);
-        if f(&(&x.key, &x.value)) { each(&x.right, f) }
+        if f(&x.key, &x.value) { each(&x.right, f) }
     }
 }
 
 fn each_reverse<'r, K: TotalOrd, V>(node: &'r Option<~TreeNode<K, V>>,
-                                    f: &fn(&(&'r K, &'r V)) -> bool) {
+                                    f: &fn(&'r K, &'r V) -> bool) {
     for node.each |x| {
         each_reverse(&x.right, f);
-        if f(&(&x.key, &x.value)) { each_reverse(&x.left, f) }
+        if f(&x.key, &x.value) { each_reverse(&x.left, f) }
     }
 }
 
@@ -796,7 +790,7 @@ mod test_treemap {
             let &(k, v) = x;
             assert!(map.find(&k).unwrap() == &v)
         }
-        for map.each |&(map_k, map_v)| {
+        for map.each |map_k, map_v| {
             let mut found = false;
             for ctrl.each |x| {
                 let &(ctrl_k, ctrl_v) = x;
@@ -912,7 +906,7 @@ mod test_treemap {
         assert!(m.insert(1, 2));
 
         let mut n = 0;
-        for m.each |&(k, v)| {
+        for m.each |k, v| {
             assert!(*k == n);
             assert!(*v == n * 2);
             n += 1;
@@ -930,7 +924,7 @@ mod test_treemap {
         assert!(m.insert(1, 2));
 
         let mut n = 4;
-        for m.each_reverse |&(k, v)| {
+        for m.each_reverse |k, v| {
             assert!(*k == n);
             assert!(*v == n * 2);
             n -= 1;
diff --git a/src/libstd/workcache.rs b/src/libstd/workcache.rs
index 3e494d0236e..c4b450810aa 100644
--- a/src/libstd/workcache.rs
+++ b/src/libstd/workcache.rs
@@ -145,7 +145,7 @@ impl WorkMap {
 impl<S:Encoder> Encodable<S> for WorkMap {
     fn encode(&self, s: &S) {
         let mut d = ~[];
-        for self.each |&(k, v)| {
+        for self.each |k, v| {
             d.push((copy *k, copy *v))
         }
         sort::tim_sort(d);
@@ -319,7 +319,7 @@ impl TPrep for Prep {
     }
 
     fn all_fresh(&self, cat: &str, map: &WorkMap) -> bool {
-        for map.each |&(k, v)| {
+        for map.each |k, v| {
             if ! self.is_fresh(cat, k.kind, k.name, *v) {
                 return false;
             }
diff --git a/src/test/bench/shootout-k-nucleotide-pipes.rs b/src/test/bench/shootout-k-nucleotide-pipes.rs
index 6ba1caa0d1e..c8b13a6e27f 100644
--- a/src/test/bench/shootout-k-nucleotide-pipes.rs
+++ b/src/test/bench/shootout-k-nucleotide-pipes.rs
@@ -48,7 +48,7 @@ fn sort_and_fmt(mm: &HashMap<~[u8], uint>, total: uint) -> ~str {
    let mut pairs = ~[];
 
    // map -> [(k,%)]
-   for mm.each |&(&key, &val)| {
+   for mm.each |&key, &val| {
       pairs.push((key, pct(val, total)));
    }
 
diff --git a/src/test/run-pass/class-impl-very-parameterized-trait.rs b/src/test/run-pass/class-impl-very-parameterized-trait.rs
index 30ca5ea3881..cfde61d74b2 100644
--- a/src/test/run-pass/class-impl-very-parameterized-trait.rs
+++ b/src/test/run-pass/class-impl-very-parameterized-trait.rs
@@ -49,18 +49,6 @@ pub impl<T> cat<T> {
     }
 }
 
-impl<'self,T> BaseIter<(int, &'self T)> for cat<T> {
-    fn each(&self, f: &fn(&(int, &'self T)) -> bool) {
-        let mut n = int::abs(self.meows);
-        while n > 0 {
-            if !f(&(n, &self.name)) { break; }
-            n -= 1;
-        }
-    }
-
-    fn size_hint(&self) -> Option<uint> { Some(self.len()) }
-}
-
 impl<T> Container for cat<T> {
     fn len(&const self) -> uint { self.meows as uint }
     fn is_empty(&const self) -> bool { self.meows == 0 }
@@ -71,17 +59,25 @@ impl<T> Mutable for cat<T> {
 }
 
 impl<T> Map<int, T> for cat<T> {
+    fn each(&self, f: &fn(&int, &T) -> bool) {
+        let mut n = int::abs(self.meows);
+        while n > 0 {
+            if !f(&n, &self.name) { break; }
+            n -= 1;
+        }
+    }
+
     fn contains_key(&self, k: &int) -> bool { *k <= self.meows }
 
     fn each_key(&self, f: &fn(v: &int) -> bool) {
-        for self.each |&(k, _)| { if !f(&k) { break; } loop;};
+        for self.each |k, _| { if !f(k) { break; } loop;};
     }
 
     fn each_value(&self, f: &fn(v: &T) -> bool) {
-        for self.each |&(_, v)| { if !f(v) { break; } loop;};
+        for self.each |_, v| { if !f(v) { break; } loop;};
     }
 
-    fn mutate_values(&mut self, f: &fn(&int, &mut T) -> bool) {
+    fn mutate_values(&mut self, _f: &fn(&int, &mut T) -> bool) {
         fail!(~"nope")
     }
 
@@ -98,7 +94,7 @@ impl<T> Map<int, T> for cat<T> {
         }
     }
 
-    fn find_mut(&mut self, k: &int) -> Option<&'self mut T> { fail!() }
+    fn find_mut(&mut self, _k: &int) -> Option<&'self mut T> { fail!() }
 
     fn remove(&mut self, k: &int) -> bool {
         if self.find(k).is_some() {