diff --git a/src/libcargo/cargo.rc b/src/libcargo/cargo.rc
index 79bf85021d8..db976b580c7 100644
--- a/src/libcargo/cargo.rc
+++ b/src/libcargo/cargo.rc
@@ -730,7 +730,7 @@ pub fn configure(opts: Options) -> Cargo {
     need_dir(&c.libdir);
     need_dir(&c.bindir);
 
-    for sources.each_key_ref |&k| {
+    for sources.each_key |&k| {
         let mut s = sources.get(&k);
         load_source_packages(&c, s);
         sources.insert(k, s);
@@ -748,7 +748,7 @@ pub fn configure(opts: Options) -> Cargo {
 }
 
 pub fn for_each_package(c: &Cargo, b: fn(s: @Source, p: &Package)) {
-    for c.sources.each_value_ref |&v| {
+    for c.sources.each_value |&v| {
         for v.packages.each |p| {
             b(v, p);
         }
@@ -1155,7 +1155,7 @@ pub fn cmd_install(c: &mut Cargo) {
 }
 
 pub fn sync(c: &Cargo) {
-    for c.sources.each_key_ref |&k| {
+    for c.sources.each_key |&k| {
         let mut s = c.sources.get(&k);
         sync_one(c, s);
         c.sources.insert(k, s);
@@ -1569,7 +1569,7 @@ pub fn cmd_list(c: &Cargo) {
             }
         }
     } else {
-        for c.sources.each_value_ref |&v| {
+        for c.sources.each_value |&v| {
             print_source(v);
         }
     }
@@ -1636,7 +1636,7 @@ pub fn dump_sources(c: &Cargo) {
         result::Ok(writer) => {
             let mut hash = ~LinearMap::new();
 
-            for c.sources.each_ref |&k, &v| {
+            for c.sources.each |&k, &v| {
                 let mut chash = ~LinearMap::new();
 
                 chash.insert(~"url", json::String(v.url));
@@ -1675,7 +1675,7 @@ pub fn copy_warn(srcfile: &Path, destfile: &Path) {
 
 pub fn cmd_sources(c: &Cargo) {
     if vec::len(c.opts.free) < 3u {
-        for c.sources.each_value_ref |&v| {
+        for c.sources.each_value |&v| {
             info(fmt!("%s (%s) via %s",
                       v.name, v.url, v.method));
         }
@@ -1686,7 +1686,7 @@ pub fn cmd_sources(c: &Cargo) {
 
     match action {
         ~"clear" => {
-          for c.sources.each_key_ref |&k| {
+          for c.sources.each_key |&k| {
                 c.sources.remove(&k);
             }
 
@@ -1706,7 +1706,7 @@ pub fn cmd_sources(c: &Cargo) {
                 return;
             }
 
-            if c.sources.contains_key_ref(&name) {
+            if c.sources.contains_key(&name) {
                 error(fmt!("source already exists: %s", name));
             } else {
                 c.sources.insert(name, @Source {
@@ -1733,7 +1733,7 @@ pub fn cmd_sources(c: &Cargo) {
                 return;
             }
 
-            if c.sources.contains_key_ref(&name) {
+            if c.sources.contains_key(&name) {
                 c.sources.remove(&name);
                 info(fmt!("removed source: %s", name));
             } else {
diff --git a/src/librustc/back/rpath.rs b/src/librustc/back/rpath.rs
index f6a5fec75ad..4cca6757cc3 100644
--- a/src/librustc/back/rpath.rs
+++ b/src/librustc/back/rpath.rs
@@ -18,8 +18,7 @@ use core::os;
 use core::uint;
 use core::util;
 use core::vec;
-use std::oldmap::HashMap;
-use std::oldmap;
+use core::hashmap::linear::LinearSet;
 
 pure fn not_win32(os: session::os) -> bool {
   match os {
@@ -187,16 +186,14 @@ pub fn get_install_prefix_rpath(target_triple: &str) -> Path {
 }
 
 pub fn minimize_rpaths(rpaths: &[Path]) -> ~[Path] {
-    let set = oldmap::HashMap();
+    let mut set = LinearSet::new();
     let mut minimized = ~[];
     for rpaths.each |rpath| {
-        let s = rpath.to_str();
-        if !set.contains_key_ref(&s) {
-            minimized.push(/*bad*/copy *rpath);
-            set.insert(s, ());
+        if set.insert(rpath.to_str()) {
+            minimized.push(copy *rpath);
         }
     }
-    return minimized;
+    minimized
 }
 
 #[cfg(unix)]
diff --git a/src/librustc/metadata/cstore.rs b/src/librustc/metadata/cstore.rs
index c144d2d8804..73ec872b6a6 100644
--- a/src/librustc/metadata/cstore.rs
+++ b/src/librustc/metadata/cstore.rs
@@ -86,13 +86,13 @@ pub fn set_crate_data(cstore: @mut CStore,
 }
 
 pub fn have_crate_data(cstore: @mut CStore, cnum: ast::crate_num) -> bool {
-    return cstore.metas.contains_key_ref(&cnum);
+    cstore.metas.contains_key(&cnum)
 }
 
 pub fn iter_crate_data(cstore: @mut CStore,
                        i: fn(ast::crate_num, crate_metadata)) {
     let metas = cstore.metas;
-    for metas.each_ref |&k, &v| {
+    for metas.each |&k, &v| {
         i(k, v);
     }
 }
@@ -148,7 +148,7 @@ pub fn get_dep_hashes(cstore: @mut CStore) -> ~[~str] {
     let mut result = ~[];
 
     let use_crate_map = cstore.use_crate_map;
-    for use_crate_map.each_value_ref |&cnum| {
+    for use_crate_map.each_value |&cnum| {
         let cdata = cstore::get_crate_data(cstore, cnum);
         let hash = decoder::get_crate_hash(cdata.data);
         debug!("Add hash[%s]: %s", cdata.name, hash);
diff --git a/src/librustc/metadata/encoder.rs b/src/librustc/metadata/encoder.rs
index 89b491a867b..fcc1a4e806d 100644
--- a/src/librustc/metadata/encoder.rs
+++ b/src/librustc/metadata/encoder.rs
@@ -99,7 +99,7 @@ pub enum encode_ctxt = {
 };
 
 pub fn reachable(ecx: @encode_ctxt, id: node_id) -> bool {
-    ecx.reachable.contains_key_ref(&id)
+    ecx.reachable.contains_key(&id)
 }
 
 fn encode_name(ecx: @encode_ctxt, ebml_w: writer::Encoder, name: ident) {
diff --git a/src/librustc/middle/borrowck/check_loans.rs b/src/librustc/middle/borrowck/check_loans.rs
index 8d439f4ee9f..251fec68486 100644
--- a/src/librustc/middle/borrowck/check_loans.rs
+++ b/src/librustc/middle/borrowck/check_loans.rs
@@ -689,7 +689,7 @@ fn check_loans_in_expr(expr: @ast::expr,
 
     self.check_for_conflicting_loans(expr.id);
 
-    if self.bccx.moves_map.contains_key_ref(&expr.id) {
+    if self.bccx.moves_map.contains_key(&expr.id) {
         self.check_move_out_from_expr(expr);
     }
 
@@ -710,7 +710,7 @@ fn check_loans_in_expr(expr: @ast::expr,
       }
       ast::expr_index(_, rval) |
       ast::expr_binary(_, _, rval)
-      if self.bccx.method_map.contains_key_ref(&expr.id) => {
+      if self.bccx.method_map.contains_key(&expr.id) => {
         self.check_call(expr,
                         None,
                         expr.callee_id,
@@ -718,7 +718,7 @@ fn check_loans_in_expr(expr: @ast::expr,
                         ~[rval]);
       }
       ast::expr_unary(*) | ast::expr_index(*)
-      if self.bccx.method_map.contains_key_ref(&expr.id) => {
+      if self.bccx.method_map.contains_key(&expr.id) => {
         self.check_call(expr,
                         None,
                         expr.callee_id,
diff --git a/src/librustc/middle/borrowck/gather_loans.rs b/src/librustc/middle/borrowck/gather_loans.rs
index 6a61b2e2ee7..d4c45828858 100644
--- a/src/librustc/middle/borrowck/gather_loans.rs
+++ b/src/librustc/middle/borrowck/gather_loans.rs
@@ -207,7 +207,7 @@ fn req_loans_in_expr(ex: @ast::expr,
       ast::expr_binary(_, rcvr, _) |
       ast::expr_unary(_, rcvr) |
       ast::expr_assign_op(_, rcvr, _)
-      if self.bccx.method_map.contains_key_ref(&ex.id) => {
+      if self.bccx.method_map.contains_key(&ex.id) => {
         // Receivers in method calls are always passed by ref.
         //
         // Here, in an overloaded operator, the call is this expression,
@@ -244,7 +244,7 @@ fn req_loans_in_expr(ex: @ast::expr,
       // }
 
       ast::expr_field(rcvr, _, _)
-      if self.bccx.method_map.contains_key_ref(&ex.id) => {
+      if self.bccx.method_map.contains_key(&ex.id) => {
         // Receivers in method calls are always passed by ref.
         //
         // Here, the field a.b is in fact a closure.  Eventually, this
diff --git a/src/librustc/middle/borrowck/preserve.rs b/src/librustc/middle/borrowck/preserve.rs
index 1946ba09ec7..097f0579362 100644
--- a/src/librustc/middle/borrowck/preserve.rs
+++ b/src/librustc/middle/borrowck/preserve.rs
@@ -375,7 +375,7 @@ impl PreserveCtxt {
                 // scope_id;`. Though that would potentially re-introduce
                 // the ICE. See #3511 for more details.
                 let scope_to_use = if
-                    self.bccx.stmt_map.contains_key_ref(&scope_id) {
+                    self.bccx.stmt_map.contains_key(&scope_id) {
                     // Root it in its parent scope, b/c
                     // trans won't introduce a new scope for the
                     // stmt
diff --git a/src/librustc/middle/check_const.rs b/src/librustc/middle/check_const.rs
index ad46d3b6f4d..6cca576fa13 100644
--- a/src/librustc/middle/check_const.rs
+++ b/src/librustc/middle/check_const.rs
@@ -102,7 +102,7 @@ pub fn check_expr(sess: Session,
           }
           expr_lit(@codemap::spanned {node: lit_str(_), _}) => { }
           expr_binary(_, _, _) | expr_unary(_, _) => {
-            if method_map.contains_key_ref(&e.id) {
+            if method_map.contains_key(&e.id) {
                 sess.span_err(e.span, ~"user-defined operators are not \
                                        allowed in constant expressions");
             }
diff --git a/src/librustc/middle/check_match.rs b/src/librustc/middle/check_match.rs
index 6f9fe1edca5..1a3e4251129 100644
--- a/src/librustc/middle/check_match.rs
+++ b/src/librustc/middle/check_match.rs
@@ -59,7 +59,7 @@ pub fn expr_is_non_moving_lvalue(cx: @MatchCheckCtxt, expr: @expr) -> bool {
         return false;
     }
 
-    !cx.moves_map.contains_key_ref(&expr.id)
+    !cx.moves_map.contains_key(&expr.id)
 }
 
 pub fn check_expr(cx: @MatchCheckCtxt, ex: @expr, &&s: (), v: visit::vt<()>) {
@@ -734,7 +734,7 @@ pub fn check_legality_of_move_bindings(cx: @MatchCheckCtxt,
                     by_ref_span = Some(span);
                 }
                 bind_infer => {
-                    if cx.moves_map.contains_key_ref(&id) {
+                    if cx.moves_map.contains_key(&id) {
                         any_by_move = true;
                     }
                 }
@@ -774,7 +774,7 @@ pub fn check_legality_of_move_bindings(cx: @MatchCheckCtxt,
             if pat_is_binding(def_map, p) {
                 match p.node {
                     pat_ident(_, _, sub) => {
-                        if cx.moves_map.contains_key_ref(&p.id) {
+                        if cx.moves_map.contains_key(&p.id) {
                             check_move(p, sub);
                         }
                     }
@@ -800,7 +800,7 @@ pub fn check_legality_of_move_bindings(cx: @MatchCheckCtxt,
                                 behind_bad_pointer);
 
                         if behind_bad_pointer &&
-                            cx.moves_map.contains_key_ref(&pat.id)
+                            cx.moves_map.contains_key(&pat.id)
                         {
                             cx.tcx.sess.span_err(
                                 pat.span,
diff --git a/src/librustc/middle/freevars.rs b/src/librustc/middle/freevars.rs
index e6091077210..0d3b7c36f6d 100644
--- a/src/librustc/middle/freevars.rs
+++ b/src/librustc/middle/freevars.rs
@@ -69,7 +69,7 @@ fn collect_freevars(def_map: resolve::DefMap, blk: ast::blk)
                       }
                       if i == depth { // Made it to end of loop
                         let dnum = ast_util::def_id_of_def(def).node;
-                        if !seen.contains_key_ref(&dnum) {
+                        if !seen.contains_key(&dnum) {
                             refs.push(@freevar_entry {
                                 def: def,
                                 span: expr.span,
diff --git a/src/librustc/middle/lang_items.rs b/src/librustc/middle/lang_items.rs
index b4500f87eb0..6bcc71514d4 100644
--- a/src/librustc/middle/lang_items.rs
+++ b/src/librustc/middle/lang_items.rs
@@ -391,7 +391,7 @@ impl LanguageItemCollector {
     }
 
     fn check_completeness() {
-        for self.item_refs.each_ref |&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 843b01bdb35..487148ddd97 100644
--- a/src/librustc/middle/lint.rs
+++ b/src/librustc/middle/lint.rs
@@ -400,7 +400,7 @@ pub fn build_settings_crate(sess: session::Session, crate: @ast::crate) {
                     sess: sess});
 
     // Install defaults.
-    for cx.dict.each_value_ref |&spec| {
+    for cx.dict.each_value |&spec| {
         cx.set_level(spec.lint, spec.default);
     }
 
diff --git a/src/librustc/middle/mem_categorization.rs b/src/librustc/middle/mem_categorization.rs
index 07de9987096..fd9271af6c6 100644
--- a/src/librustc/middle/mem_categorization.rs
+++ b/src/librustc/middle/mem_categorization.rs
@@ -340,7 +340,7 @@ pub impl &mem_categorization_ctxt {
         let expr_ty = tcx.ty(expr);
         match expr.node {
           ast::expr_unary(ast::deref, e_base) => {
-            if self.method_map.contains_key_ref(&expr.id) {
+            if self.method_map.contains_key(&expr.id) {
                 return self.cat_rvalue(expr, expr_ty);
             }
 
@@ -349,7 +349,7 @@ pub impl &mem_categorization_ctxt {
           }
 
           ast::expr_field(base, f_name, _) => {
-            if self.method_map.contains_key_ref(&expr.id) {
+            if self.method_map.contains_key(&expr.id) {
                 return self.cat_method_ref(expr, expr_ty);
             }
 
@@ -358,7 +358,7 @@ pub impl &mem_categorization_ctxt {
           }
 
           ast::expr_index(base, _) => {
-            if self.method_map.contains_key_ref(&expr.id) {
+            if self.method_map.contains_key(&expr.id) {
                 return self.cat_rvalue(expr, expr_ty);
             }
 
diff --git a/src/librustc/middle/moves.rs b/src/librustc/middle/moves.rs
index 0d32bb7ecf6..b23066c1d96 100644
--- a/src/librustc/middle/moves.rs
+++ b/src/librustc/middle/moves.rs
@@ -668,7 +668,7 @@ impl VisitContext {
                                arg_exprs: &[@expr],
                                visitor: vt<VisitContext>) -> bool
     {
-        if !self.method_map.contains_key_ref(&expr.id) {
+        if !self.method_map.contains_key(&expr.id) {
             return false;
         }
 
@@ -799,7 +799,7 @@ impl VisitContext {
             for arm.pats.each |pat| {
                 let mut found = false;
                 do pat_bindings(self.tcx.def_map, *pat) |_, node_id, _, _| {
-                    if moves_map.contains_key_ref(&node_id) {
+                    if moves_map.contains_key(&node_id) {
                         found = true;
                     }
                 }
diff --git a/src/librustc/middle/region.rs b/src/librustc/middle/region.rs
index 49b373fe6b1..5b2d3c9bb96 100644
--- a/src/librustc/middle/region.rs
+++ b/src/librustc/middle/region.rs
@@ -296,7 +296,7 @@ pub fn resolve_expr(expr: @ast::expr, cx: ctxt, visitor: visit::vt<ctxt>) {
       _ => {}
     };
 
-    if new_cx.root_exprs.contains_key_ref(&expr.id) {
+    if new_cx.root_exprs.contains_key(&expr.id) {
         new_cx.parent = Some(expr.id);
     }
 
@@ -840,7 +840,7 @@ 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_ref |&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 51df1d05d9e..ba550dbbde8 100644
--- a/src/librustc/middle/resolve.rs
+++ b/src/librustc/middle/resolve.rs
@@ -1942,7 +1942,7 @@ pub impl Resolver {
                self.module_to_str(module_));
         self.resolve_imports_for_module(module_);
 
-        for module_.children.each_value_ref |&child_node| {
+        for module_.children.each_value |&child_node| {
             match child_node.get_module_if_available() {
                 None => {
                     // Nothing to do.
@@ -1953,7 +1953,7 @@ pub impl Resolver {
             }
         }
 
-        for module_.anonymous_children.each_value_ref |&child_module| {
+        for module_.anonymous_children.each_value |&child_module| {
             self.resolve_imports_for_module_subtree(child_module);
         }
     }
@@ -2241,7 +2241,7 @@ pub impl Resolver {
         }
 
         // We've successfully resolved the import. Write the results in.
-        assert module_.import_resolutions.contains_key_ref(&target);
+        assert module_.import_resolutions.contains_key(&target);
         let import_resolution = module_.import_resolutions.get(&target);
 
         match value_result {
@@ -2400,7 +2400,7 @@ pub impl Resolver {
         }
 
         // We've successfully resolved the import. Write the results in.
-        assert module_.import_resolutions.contains_key_ref(&target);
+        assert module_.import_resolutions.contains_key(&target);
         let import_resolution = module_.import_resolutions.get(&target);
 
         match module_result {
@@ -2461,7 +2461,7 @@ pub impl Resolver {
         assert containing_module.glob_count == 0;
 
         // Add all resolved imports from the containing module.
-        for containing_module.import_resolutions.each_ref
+        for containing_module.import_resolutions.each
                 |&ident, &target_import_resolution| {
 
             debug!("(resolving glob import) writing module resolution \
@@ -2512,7 +2512,7 @@ pub impl Resolver {
         }
 
         // Add all children from the containing module.
-        for containing_module.children.each_ref |&ident, &name_bindings| {
+        for containing_module.children.each |&ident, &name_bindings| {
             let mut dest_import_resolution;
             match module_.import_resolutions.find(&ident) {
                 None => {
@@ -3182,7 +3182,7 @@ pub impl Resolver {
         }
 
         // Descend into children and anonymous children.
-        for module_.children.each_value_ref |&child_node| {
+        for module_.children.each_value |&child_node| {
             match child_node.get_module_if_available() {
                 None => {
                     // Continue.
@@ -3193,7 +3193,7 @@ pub impl Resolver {
             }
         }
 
-        for module_.anonymous_children.each_value_ref |&module_| {
+        for module_.anonymous_children.each_value |&module_| {
             self.report_unresolved_imports(module_);
         }
     }
@@ -3238,7 +3238,7 @@ pub impl Resolver {
 
         self.record_exports_for_module(module_);
 
-        for module_.children.each_value_ref |&child_name_bindings| {
+        for module_.children.each_value |&child_name_bindings| {
             match child_name_bindings.get_module_if_available() {
                 None => {
                     // Nothing to do.
@@ -3249,7 +3249,7 @@ pub impl Resolver {
             }
         }
 
-        for module_.anonymous_children.each_value_ref |&child_module| {
+        for module_.anonymous_children.each_value |&child_module| {
             self.record_exports_for_module_subtree(child_module);
         }
     }
@@ -3297,7 +3297,7 @@ pub impl Resolver {
     }
 
     fn add_exports_for_module(exports2: &mut ~[Export2], module_: @Module) {
-        for module_.children.each_ref |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,
@@ -3312,7 +3312,7 @@ pub impl Resolver {
                                              false);
         }
 
-        for module_.import_resolutions.each_ref |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));
@@ -4102,7 +4102,7 @@ pub impl Resolver {
         for arm.pats.eachi() |i, p| {
             let map_i = self.binding_mode_map(*p);
 
-            for map_0.each_ref |&key, &binding_0| {
+            for map_0.each |&key, &binding_0| {
                 match map_i.find(&key) {
                   None => {
                     self.session.span_err(
@@ -4123,8 +4123,8 @@ pub impl Resolver {
                 }
             }
 
-            for map_i.each_ref |&key, &binding| {
-                if !map_0.contains_key_ref(&key) {
+            for map_i.each |&key, &binding| {
+                if !map_0.contains_key(&key) {
                     self.session.span_err(
                         binding.span,
                         fmt!("variable `%s` from pattern #%u is \
@@ -4353,7 +4353,7 @@ pub impl Resolver {
 
                             match bindings_list {
                                 Some(bindings_list)
-                                if !bindings_list.contains_key_ref(&ident)
+                                if !bindings_list.contains_key(&ident)
                                     => {
                                     let last_rib = (*self.value_ribs).last();
                                     last_rib.bindings.insert(ident,
@@ -4426,18 +4426,18 @@ pub impl Resolver {
                 pat_struct(path, _, _) => {
                     match self.resolve_path(path, TypeNS, false, visitor) {
                         Some(def_ty(class_id))
-                                if self.structs.contains_key_ref(&class_id)
+                                if self.structs.contains_key(&class_id)
                                      => {
                             let class_def = def_struct(class_id);
                             self.record_def(pattern.id, class_def);
                         }
                         Some(definition @ def_struct(class_id))
-                                if self.structs.contains_key_ref(&class_id)
+                                if self.structs.contains_key(&class_id)
                                      => {
                             self.record_def(pattern.id, definition);
                         }
                         Some(definition @ def_variant(_, variant_id))
-                                if self.structs.contains_key_ref(&variant_id)
+                                if self.structs.contains_key(&variant_id)
                                      => {
                             self.record_def(pattern.id, definition);
                         }
@@ -4886,12 +4886,12 @@ pub impl Resolver {
 
                 match self.resolve_path(path, TypeNS, false, visitor) {
                     Some(def_ty(class_id)) | Some(def_struct(class_id))
-                            if self.structs.contains_key_ref(&class_id) => {
+                            if self.structs.contains_key(&class_id) => {
                         let class_def = def_struct(class_id);
                         self.record_def(expr.id, class_def);
                     }
                     Some(definition @ def_variant(_, class_id))
-                            if self.structs.contains_key_ref(&class_id) => {
+                            if self.structs.contains_key(&class_id) => {
                         self.record_def(expr.id, definition);
                     }
                     _ => {
@@ -5035,7 +5035,7 @@ pub impl Resolver {
             }
 
             // Look for trait children.
-            for search_module.children.each_value_ref |&child_name_bindings| {
+            for search_module.children.each_value |&child_name_bindings| {
                 match child_name_bindings.def_for_namespace(TypeNS) {
                     Some(def) => {
                         match def {
@@ -5055,7 +5055,7 @@ pub impl Resolver {
             }
 
             // Look for imports.
-            for search_module.import_resolutions.each_value_ref
+            for search_module.import_resolutions.each_value
                     |&import_resolution| {
 
                 match import_resolution.target_for_namespace(TypeNS) {
@@ -5115,7 +5115,7 @@ pub impl Resolver {
                self.session.str_of(name));
 
         match self.trait_info.find(&trait_def_id) {
-            Some(trait_info) if trait_info.contains_key_ref(&name) => {
+            Some(trait_info) if trait_info.contains_key(&name) => {
                 debug!("(adding trait info if containing method) found trait \
                         %d:%d for method '%s'",
                        trait_def_id.crate,
@@ -5223,7 +5223,7 @@ pub impl Resolver {
 
         self.check_for_unused_imports_in_module(module_);
 
-        for module_.children.each_value_ref |&child_name_bindings| {
+        for module_.children.each_value |&child_name_bindings| {
             match (*child_name_bindings).get_module_if_available() {
                 None => {
                     // Nothing to do.
@@ -5235,13 +5235,13 @@ pub impl Resolver {
             }
         }
 
-        for module_.anonymous_children.each_value_ref |&child_module| {
+        for module_.anonymous_children.each_value |&child_module| {
             self.check_for_unused_imports_in_module_subtree(child_module);
         }
     }
 
     fn check_for_unused_imports_in_module(module_: @Module) {
-        for module_.import_resolutions.each_value_ref |&import_resolution| {
+        for module_.import_resolutions.each_value |&import_resolution| {
             // Ignore dummy spans for things like automatically injected
             // imports for the prelude, and also don't warn about the same
             // import statement being unused more than once.
@@ -5306,12 +5306,12 @@ pub impl Resolver {
         debug!("Dump of module `%s`:", self.module_to_str(module_));
 
         debug!("Children:");
-        for module_.children.each_key_ref |&name| {
+        for module_.children.each_key |&name| {
             debug!("* %s", self.session.str_of(name));
         }
 
         debug!("Import resolutions:");
-        for module_.import_resolutions.each_ref |&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/_match.rs b/src/librustc/middle/trans/_match.rs
index ebd6d9f9056..2369a63e544 100644
--- a/src/librustc/middle/trans/_match.rs
+++ b/src/librustc/middle/trans/_match.rs
@@ -1096,7 +1096,7 @@ pub fn store_non_ref_bindings(bcx: block,
      */
 
     let mut bcx = bcx;
-    for data.bindings_map.each_value_ref |&binding_info| {
+    for data.bindings_map.each_value |&binding_info| {
         match binding_info.trmode {
             TrByValue(is_move, lldest) => {
                 let llval = Load(bcx, binding_info.llmatch); // get a T*
@@ -1130,7 +1130,7 @@ pub fn insert_lllocals(bcx: block,
      * the `fcx.lllocals` map.  If add_cleans is true, then adds cleanups for
      * the bindings. */
 
-    for data.bindings_map.each_value_ref |&binding_info| {
+    for data.bindings_map.each_value |&binding_info| {
         let llval = match binding_info.trmode {
             // By value bindings: use the stack slot that we
             // copied/moved the value into
@@ -1203,7 +1203,7 @@ pub fn compile_guard(bcx: block,
 
     fn drop_bindings(bcx: block, data: &ArmData) -> block {
         let mut bcx = bcx;
-        for data.bindings_map.each_value_ref |&binding_info| {
+        for data.bindings_map.each_value |&binding_info| {
             match binding_info.trmode {
                 TrByValue(_, llval) => {
                     bcx = glue::drop_ty(bcx, llval, binding_info.ty);
@@ -1598,7 +1598,7 @@ pub fn trans_match_inner(scope_cx: block,
                     // but during matching we need to store a *T as explained
                     // above
                     let is_move =
-                        scope_cx.ccx().maps.moves_map.contains_key_ref(&p_id);
+                        scope_cx.ccx().maps.moves_map.contains_key(&p_id);
                     llmatch = alloca(bcx, T_ptr(llvariable_ty));
                     trmode = TrByValue(is_move, alloca(bcx, llvariable_ty));
                 }
diff --git a/src/librustc/middle/trans/base.rs b/src/librustc/middle/trans/base.rs
index acf33434b2f..ced47bb5681 100644
--- a/src/librustc/middle/trans/base.rs
+++ b/src/librustc/middle/trans/base.rs
@@ -169,7 +169,7 @@ pub fn get_extern_fn(externs: ExternMap,
                      name: @str,
                      cc: lib::llvm::CallConv,
                      ty: TypeRef) -> ValueRef {
-    if externs.contains_key_ref(&name) { return externs.get(&name); }
+    if externs.contains_key(&name) { return externs.get(&name); }
     let f = decl_fn(llmod, name, cc, ty);
     externs.insert(name, f);
     return f;
@@ -178,7 +178,7 @@ pub fn get_extern_fn(externs: ExternMap,
 pub fn get_extern_const(externs: ExternMap, llmod: ModuleRef,
                         name: @str, ty: TypeRef) -> ValueRef {
     unsafe {
-        if externs.contains_key_ref(&name) { return externs.get(&name); }
+        if externs.contains_key(&name) { return externs.get(&name); }
         let c = str::as_c_str(name, |buf| {
             llvm::LLVMAddGlobal(llmod, ty, buf)
         });
@@ -448,7 +448,7 @@ pub fn set_glue_inlining(f: ValueRef, t: ty::t) {
 // silently mangles such symbols, breaking our linkage model.
 pub fn note_unique_llvm_symbol(ccx: @crate_ctxt, +sym: ~str) {
     // XXX: Bad copy.
-    if ccx.all_llvm_symbols.contains_key_ref(&sym) {
+    if ccx.all_llvm_symbols.contains_key(&sym) {
         ccx.sess.bug(~"duplicate LLVM symbol: " + sym);
     }
     ccx.all_llvm_symbols.insert(sym, ());
@@ -2477,7 +2477,7 @@ pub fn get_item_val(ccx: @crate_ctxt, id: ast::node_id) -> ValueRef {
             ccx.sess.bug(~"get_item_val(): unexpected variant")
           }
         };
-        if !(exprt || ccx.reachable.contains_key_ref(&id)) {
+        if !(exprt || ccx.reachable.contains_key(&id)) {
             lib::llvm::SetLinkage(val, lib::llvm::InternalLinkage);
         }
         ccx.item_vals.insert(id, val);
@@ -2800,7 +2800,7 @@ pub fn create_module_map(ccx: @crate_ctxt) -> ValueRef {
         lib::llvm::SetLinkage(map, lib::llvm::InternalLinkage);
     }
     let mut elts: ~[ValueRef] = ~[];
-    for ccx.module_data.each_ref |&key, &val| {
+    for ccx.module_data.each |&key, &val| {
         let elt = C_struct(~[p2i(ccx, C_cstr(ccx, key)),
                             p2i(ccx, val)]);
         elts.push(elt);
@@ -3084,7 +3084,7 @@ pub fn trans_crate(sess: session::Session,
         }
 
         if ccx.sess.count_llvm_insns() {
-            for ccx.stats.llvm_insns.each_ref |&k, &v| {
+            for ccx.stats.llvm_insns.each |&k, &v| {
                 io::println(fmt!("%-7u %s", v, k));
             }
         }
diff --git a/src/librustc/middle/trans/callee.rs b/src/librustc/middle/trans/callee.rs
index 08bab21daaf..81fa221aac4 100644
--- a/src/librustc/middle/trans/callee.rs
+++ b/src/librustc/middle/trans/callee.rs
@@ -674,8 +674,7 @@ pub fn trans_arg_expr(bcx: block,
         // FIXME(#3548) use the adjustments table
         match autoref_arg {
             DoAutorefArg => {
-                assert !bcx.ccx().maps.moves_map.contains_key_ref(
-                    &arg_expr.id);
+                assert !bcx.ccx().maps.moves_map.contains_key(&arg_expr.id);
                 val = arg_datum.to_ref_llval(bcx);
             }
             DontAutorefArg => {
@@ -685,7 +684,7 @@ pub fn trans_arg_expr(bcx: block,
                         // the explicit self code currently passes by-ref, it
                         // does not hold.
                         //
-                        //assert !bcx.ccx().maps.moves_map.contains_key_ref(
+                        //assert !bcx.ccx().maps.moves_map.contains_key(
                         //    &arg_expr.id);
                         val = arg_datum.to_ref_llval(bcx);
                     }
@@ -693,7 +692,7 @@ pub fn trans_arg_expr(bcx: block,
                     ast::by_val => {
                         // NB: avoid running the take glue.
 
-                        assert !bcx.ccx().maps.moves_map.contains_key_ref(
+                        assert !bcx.ccx().maps.moves_map.contains_key(
                             &arg_expr.id);
                         val = arg_datum.to_value_llval(bcx);
                     }
diff --git a/src/librustc/middle/trans/consts.rs b/src/librustc/middle/trans/consts.rs
index 515239883e2..bcf796caa7a 100644
--- a/src/librustc/middle/trans/consts.rs
+++ b/src/librustc/middle/trans/consts.rs
@@ -132,7 +132,7 @@ pub fn get_const_val(cx: @crate_ctxt, def_id: ast::def_id) -> ValueRef {
     if !ast_util::is_local(def_id) {
         cx.tcx.sess.bug(~"cross-crate constants");
     }
-    if !cx.const_values.contains_key_ref(&def_id.node) {
+    if !cx.const_values.contains_key(&def_id.node) {
         match cx.tcx.items.get(&def_id.node) {
             ast_map::node_item(@ast::item {
                 node: ast::item_const(_, subexpr), _
diff --git a/src/librustc/middle/trans/controlflow.rs b/src/librustc/middle/trans/controlflow.rs
index 0933eedd5e4..792c5958822 100644
--- a/src/librustc/middle/trans/controlflow.rs
+++ b/src/librustc/middle/trans/controlflow.rs
@@ -186,7 +186,7 @@ pub fn trans_log(log_ex: @ast::expr,
     // XXX: Bad copy.
     let modname = path_str(ccx.sess, copy modpath);
 
-    let global = if ccx.module_data.contains_key_ref(&modname) {
+    let global = if ccx.module_data.contains_key(&modname) {
         ccx.module_data.get(&modname)
     } else {
         let s = link::mangle_internal_name_by_path_and_seq(
diff --git a/src/librustc/middle/trans/datum.rs b/src/librustc/middle/trans/datum.rs
index af966e4df82..d301a31357b 100644
--- a/src/librustc/middle/trans/datum.rs
+++ b/src/librustc/middle/trans/datum.rs
@@ -223,7 +223,7 @@ pub impl Datum {
          * `id` is located in the move table, but copies otherwise.
          */
 
-        if bcx.ccx().maps.moves_map.contains_key_ref(&id) {
+        if bcx.ccx().maps.moves_map.contains_key(&id) {
             self.move_to(bcx, action, dst)
         } else {
             self.copy_to(bcx, action, dst)
diff --git a/src/librustc/middle/trans/debuginfo.rs b/src/librustc/middle/trans/debuginfo.rs
index 8556bee7e84..f50cadc9671 100644
--- a/src/librustc/middle/trans/debuginfo.rs
+++ b/src/librustc/middle/trans/debuginfo.rs
@@ -117,7 +117,7 @@ pub fn mk_ctxt(+crate: ~str, intr: @ident_interner) -> debug_ctxt {
 }
 
 fn update_cache(cache: metadata_cache, mdtag: int, val: debug_metadata) {
-    let existing = if cache.contains_key_ref(&mdtag) {
+    let existing = if cache.contains_key(&mdtag) {
         cache.get(&mdtag)
     } else {
         ~[]
@@ -176,7 +176,7 @@ fn cached_metadata<T: Copy>(cache: metadata_cache,
                             eq_fn: fn(md: T) -> bool)
                          -> Option<T> {
     unsafe {
-        if cache.contains_key_ref(&mdtag) {
+        if cache.contains_key(&mdtag) {
             let items = cache.get(&mdtag);
             for items.each |item| {
                 let md: T = md_from_metadata::<T>(*item);
diff --git a/src/librustc/middle/trans/expr.rs b/src/librustc/middle/trans/expr.rs
index f2da47eb0ec..cab2adc43fa 100644
--- a/src/librustc/middle/trans/expr.rs
+++ b/src/librustc/middle/trans/expr.rs
@@ -265,7 +265,7 @@ pub fn trans_to_datum(bcx: block, expr: @ast::expr) -> DatumBlock {
 }
 
 pub fn trans_into(bcx: block, expr: @ast::expr, dest: Dest) -> block {
-    if bcx.tcx().adjustments.contains_key_ref(&expr.id) {
+    if bcx.tcx().adjustments.contains_key(&expr.id) {
         // use trans_to_datum, which is mildly less efficient but
         // which will perform the adjustments:
         let datumblock = trans_to_datum(bcx, expr);
@@ -426,7 +426,7 @@ fn trans_rvalue_datum_unadjusted(bcx: block, expr: @ast::expr) -> DatumBlock {
         }
         ast::expr_binary(op, lhs, rhs) => {
             // if overloaded, would be RvalueDpsExpr
-            assert !bcx.ccx().maps.method_map.contains_key_ref(&expr.id);
+            assert !bcx.ccx().maps.method_map.contains_key(&expr.id);
 
             return trans_binary(bcx, expr, op, lhs, rhs);
         }
@@ -1215,7 +1215,7 @@ fn trans_unary_datum(bcx: block,
     assert op != ast::deref;
 
     // if overloaded, would be RvalueDpsExpr
-    assert !bcx.ccx().maps.method_map.contains_key_ref(&un_expr.id);
+    assert !bcx.ccx().maps.method_map.contains_key(&un_expr.id);
 
     let un_ty = expr_ty(bcx, un_expr);
     let sub_ty = expr_ty(bcx, sub_expr);
diff --git a/src/librustc/middle/trans/glue.rs b/src/librustc/middle/trans/glue.rs
index 3cbc575b7c1..08d22a4fbf0 100644
--- a/src/librustc/middle/trans/glue.rs
+++ b/src/librustc/middle/trans/glue.rs
@@ -384,7 +384,7 @@ pub fn make_visit_glue(bcx: block, v: ValueRef, t: ty::t) {
     let _icx = bcx.insn_ctxt("make_visit_glue");
     let mut bcx = bcx;
     let ty_visitor_name = special_idents::ty_visitor;
-    assert bcx.ccx().tcx.intrinsic_defs.contains_key_ref(&ty_visitor_name);
+    assert bcx.ccx().tcx.intrinsic_defs.contains_key(&ty_visitor_name);
     let (trait_id, ty) = bcx.ccx().tcx.intrinsic_defs.get(&ty_visitor_name);
     let v = PointerCast(bcx, v, T_ptr(type_of::type_of(bcx.ccx(), ty)));
     bcx = reflect::emit_calls_to_trait_visit_ty(bcx, t, v, trait_id);
@@ -762,7 +762,7 @@ pub fn emit_tydescs(ccx: @crate_ctxt) {
     let _icx = ccx.insn_ctxt("emit_tydescs");
     // As of this point, allow no more tydescs to be created.
     ccx.finished_tydescs = true;
-    for ccx.tydescs.each_value_ref |&val| {
+    for ccx.tydescs.each_value |&val| {
         let glue_fn_ty = T_ptr(T_generic_glue_fn(ccx));
         let ti = val;
 
diff --git a/src/librustc/middle/trans/machine.rs b/src/librustc/middle/trans/machine.rs
index dfbc75376c7..75e494f7bfc 100644
--- a/src/librustc/middle/trans/machine.rs
+++ b/src/librustc/middle/trans/machine.rs
@@ -180,7 +180,7 @@ pub fn llalign_of(cx: @crate_ctxt, t: TypeRef) -> ValueRef {
 
 // Computes the size of the data part of an enum.
 pub fn static_size_of_enum(cx: @crate_ctxt, t: ty::t) -> uint {
-    if cx.enum_sizes.contains_key_ref(&t) { return cx.enum_sizes.get(&t); }
+    if cx.enum_sizes.contains_key(&t) { return cx.enum_sizes.get(&t); }
     match ty::get(t).sty {
       ty::ty_enum(tid, ref substs) => {
         // Compute max(variant sizes).
diff --git a/src/librustc/middle/trans/meth.rs b/src/librustc/middle/trans/meth.rs
index 1d48d2dde6b..fb487b98e15 100644
--- a/src/librustc/middle/trans/meth.rs
+++ b/src/librustc/middle/trans/meth.rs
@@ -871,7 +871,7 @@ pub fn trans_trait_cast(bcx: block,
     match vstore {
         ty::vstore_slice(*) | ty::vstore_box => {
             let mut llboxdest = GEPi(bcx, lldest, [0u, 1u]);
-            if bcx.tcx().legacy_boxed_traits.contains_key_ref(&id) {
+            if bcx.tcx().legacy_boxed_traits.contains_key(&id) {
                 // Allocate an @ box and store the value into it
                 let {bcx: new_bcx, box: llbox, body: body} =
                     malloc_boxed(bcx, v_ty);
diff --git a/src/librustc/middle/trans/reachable.rs b/src/librustc/middle/trans/reachable.rs
index 112b9ac4d07..f77aa33407d 100644
--- a/src/librustc/middle/trans/reachable.rs
+++ b/src/librustc/middle/trans/reachable.rs
@@ -95,7 +95,7 @@ fn traverse_public_mod(cx: ctx, mod_id: node_id, m: _mod) {
 }
 
 fn traverse_public_item(cx: ctx, item: @item) {
-    if cx.rmap.contains_key_ref(&item.id) { return; }
+    if cx.rmap.contains_key(&item.id) { return; }
     cx.rmap.insert(item.id, ());
     match /*bad*/copy item.node {
       item_mod(m) => traverse_public_mod(cx, item.id, m),
@@ -145,7 +145,7 @@ fn mk_ty_visitor() -> visit::vt<ctx> {
 }
 
 fn traverse_ty(ty: @Ty, cx: ctx, v: visit::vt<ctx>) {
-    if cx.rmap.contains_key_ref(&ty.id) { return; }
+    if cx.rmap.contains_key(&ty.id) { return; }
     cx.rmap.insert(ty.id, ());
 
     match ty.node {
diff --git a/src/librustc/middle/trans/reflect.rs b/src/librustc/middle/trans/reflect.rs
index 3cd6a5d1836..16677530ecd 100644
--- a/src/librustc/middle/trans/reflect.rs
+++ b/src/librustc/middle/trans/reflect.rs
@@ -331,7 +331,7 @@ pub fn emit_calls_to_trait_visit_ty(bcx: block,
                                  -> block {
     use syntax::parse::token::special_idents::tydesc;
     let final = sub_block(bcx, ~"final");
-    assert bcx.ccx().tcx.intrinsic_defs.contains_key_ref(&tydesc);
+    assert bcx.ccx().tcx.intrinsic_defs.contains_key(&tydesc);
     let (_, tydesc_ty) = bcx.ccx().tcx.intrinsic_defs.get(&tydesc);
     let tydesc_ty = type_of::type_of(bcx.ccx(), tydesc_ty);
     let mut r = Reflector {
diff --git a/src/librustc/middle/trans/type_of.rs b/src/librustc/middle/trans/type_of.rs
index f727b5a2de0..84a19cd4c04 100644
--- a/src/librustc/middle/trans/type_of.rs
+++ b/src/librustc/middle/trans/type_of.rs
@@ -93,7 +93,7 @@ pub fn type_of(cx: @crate_ctxt, t: ty::t) -> TypeRef {
     debug!("type_of %?: %?", t, ty::get(t));
 
     // Check the cache.
-    if cx.lltypes.contains_key_ref(&t) { return cx.lltypes.get(&t); }
+    if cx.lltypes.contains_key(&t) { return cx.lltypes.get(&t); }
 
     // Replace any typedef'd types with their equivalent non-typedef
     // type. This ensures that all LLVM nominal types that contain
diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty.rs
index 2a43fc8a601..4350c62af6f 100644
--- a/src/librustc/middle/ty.rs
+++ b/src/librustc/middle/ty.rs
@@ -2778,7 +2778,7 @@ pub fn node_id_to_type_params(cx: ctxt, id: ast::node_id) -> ~[t] {
 }
 
 fn node_id_has_type_params(cx: ctxt, id: ast::node_id) -> bool {
-    return cx.node_type_substs.contains_key_ref(&id);
+    cx.node_type_substs.contains_key(&id)
 }
 
 // Type accessors for substructures of types
@@ -3082,7 +3082,7 @@ pub enum ExprKind {
 pub fn expr_kind(tcx: ctxt,
                  method_map: typeck::method_map,
                  expr: @ast::expr) -> ExprKind {
-    if method_map.contains_key_ref(&expr.id) {
+    if method_map.contains_key(&expr.id) {
         // Overloaded operations are generally calls, and hence they are
         // generated via DPS.  However, assign_op (e.g., `x += y`) is an
         // exception, as its result is always unit.
@@ -4338,7 +4338,7 @@ pub fn iter_bound_traits_and_supertraits(tcx: ctxt,
                     let super_t = supertrait.tpt.ty;
                     let d_id = ty_to_def_id(super_t).expect("supertrait \
                         should be a trait ty");
-                    if !supertrait_map.contains_key_ref(&d_id) {
+                    if !supertrait_map.contains_key(&d_id) {
                         supertrait_map.insert(d_id, super_t);
                         trait_ty = super_t;
                         seen_def_ids.push(d_id);
diff --git a/src/librustc/middle/typeck/check/_match.rs b/src/librustc/middle/typeck/check/_match.rs
index 3cd2be6450d..95bed114050 100644
--- a/src/librustc/middle/typeck/check/_match.rs
+++ b/src/librustc/middle/typeck/check/_match.rs
@@ -239,7 +239,7 @@ pub fn check_struct_pat_fields(pcx: pat_ctxt,
     // Report an error if not all the fields were specified.
     if !etc {
         for class_fields.eachi |i, field| {
-            if found_fields.contains_key_ref(&i) {
+            if found_fields.contains_key(&i) {
                 loop;
             }
             tcx.sess.span_err(span,
diff --git a/src/librustc/middle/typeck/check/method.rs b/src/librustc/middle/typeck/check/method.rs
index 12e3778020a..463ae3201a4 100644
--- a/src/librustc/middle/typeck/check/method.rs
+++ b/src/librustc/middle/typeck/check/method.rs
@@ -1172,12 +1172,11 @@ pub impl LookupContext {
         match candidate.origin {
             method_static(method_id) | method_self(method_id, _)
                 | method_super(method_id, _) => {
-                bad = self.tcx().destructors.contains_key_ref(&method_id);
+                bad = self.tcx().destructors.contains_key(&method_id);
             }
             method_param(method_param { trait_id: trait_id, _ }) |
             method_trait(trait_id, _, _) => {
-                bad = self.tcx().destructor_for_type.contains_key_ref(
-                    &trait_id);
+                bad = self.tcx().destructor_for_type.contains_key(&trait_id);
             }
         }
 
diff --git a/src/librustc/middle/typeck/check/mod.rs b/src/librustc/middle/typeck/check/mod.rs
index 80be81a33b3..fda9702d582 100644
--- a/src/librustc/middle/typeck/check/mod.rs
+++ b/src/librustc/middle/typeck/check/mod.rs
@@ -3208,8 +3208,8 @@ pub fn check_intrinsic_type(ccx: @mut CrateCtxt, it: @ast::foreign_item) {
       ~"visit_tydesc" => {
           let tydesc_name = special_idents::tydesc;
           let ty_visitor_name = tcx.sess.ident_of(~"TyVisitor");
-          assert tcx.intrinsic_defs.contains_key_ref(&tydesc_name);
-          assert ccx.tcx.intrinsic_defs.contains_key_ref(&ty_visitor_name);
+          assert tcx.intrinsic_defs.contains_key(&tydesc_name);
+          assert ccx.tcx.intrinsic_defs.contains_key(&ty_visitor_name);
           let (_, tydesc_ty) = tcx.intrinsic_defs.get(&tydesc_name);
           let (_, visitor_trait) = tcx.intrinsic_defs.get(&ty_visitor_name);
           let td_ptr = ty::mk_ptr(ccx.tcx, ty::mt {ty: tydesc_ty,
diff --git a/src/librustc/middle/typeck/check/regionck.rs b/src/librustc/middle/typeck/check/regionck.rs
index 9ceace00385..c91607489ec 100644
--- a/src/librustc/middle/typeck/check/regionck.rs
+++ b/src/librustc/middle/typeck/check/regionck.rs
@@ -213,7 +213,7 @@ pub fn visit_expr(expr: @ast::expr, &&rcx: @mut Rcx, v: rvt) {
             // `constrain_auto_ref()` on all exprs.  But that causes a
             // lot of spurious errors because of how the region
             // hierarchy is setup.
-            if rcx.fcx.ccx.method_map.contains_key_ref(&callee.id) {
+            if rcx.fcx.ccx.method_map.contains_key(&callee.id) {
                 match callee.node {
                     ast::expr_field(base, _, _) => {
                         constrain_auto_ref(rcx, base);
@@ -749,7 +749,7 @@ pub mod guarantor {
         let _i = ::util::common::indenter();
 
         let guarantor = {
-            if rcx.fcx.ccx.method_map.contains_key_ref(&expr.id) {
+            if rcx.fcx.ccx.method_map.contains_key(&expr.id) {
                 None
             } else {
                 guarantor(rcx, expr)
diff --git a/src/librustc/middle/typeck/check/vtable.rs b/src/librustc/middle/typeck/check/vtable.rs
index b72c42f6af7..410b4a3e33d 100644
--- a/src/librustc/middle/typeck/check/vtable.rs
+++ b/src/librustc/middle/typeck/check/vtable.rs
@@ -268,7 +268,7 @@ pub fn lookup_vtable(vcx: &VtableContext,
                         // im is one specific impl of trait_ty.
 
                         // First, ensure we haven't processed this impl yet.
-                        if impls_seen.contains_key_ref(&im.did) {
+                        if impls_seen.contains_key(&im.did) {
                             loop;
                         }
                         impls_seen.insert(im.did, ());
diff --git a/src/librustc/middle/typeck/check/writeback.rs b/src/librustc/middle/typeck/check/writeback.rs
index 835e0557e2e..1b276199381 100644
--- a/src/librustc/middle/typeck/check/writeback.rs
+++ b/src/librustc/middle/typeck/check/writeback.rs
@@ -141,7 +141,7 @@ fn maybe_resolve_type_vars_for_node(wbcx: @mut WbCtxt,
                                     sp: span,
                                     id: ast::node_id)
                                  -> Option<ty::t> {
-    if wbcx.fcx.inh.node_types.contains_key_ref(&id) {
+    if wbcx.fcx.inh.node_types.contains_key(&id) {
         resolve_type_vars_for_node(wbcx, sp, id)
     } else {
         None
diff --git a/src/librustc/middle/typeck/coherence.rs b/src/librustc/middle/typeck/coherence.rs
index 1790bd19925..5e51c216093 100644
--- a/src/librustc/middle/typeck/coherence.rs
+++ b/src/librustc/middle/typeck/coherence.rs
@@ -418,7 +418,7 @@ pub impl CoherenceChecker {
         let coherence_info = &mut self.crate_context.coherence_info;
         let extension_methods = &coherence_info.extension_methods;
 
-        for extension_methods.each_key_ref |&trait_id| {
+        for extension_methods.each_key |&trait_id| {
             self.check_implementation_coherence_of(trait_id);
         }
     }
@@ -503,7 +503,7 @@ pub impl CoherenceChecker {
         }
 
         for ty::trait_methods(tcx, trait_did).each |method| {
-            if provided_method_idents.contains_key_ref(&method.ident) {
+            if provided_method_idents.contains_key(&method.ident) {
                 if !f(method) {
                     break;
                 }
@@ -911,7 +911,7 @@ pub impl CoherenceChecker {
         let tcx = self.crate_context.tcx;
         let pmm = tcx.provided_methods;
 
-        if pmm.contains_key_ref(&trait_def_id) { return; }
+        if pmm.contains_key(&trait_def_id) { return; }
 
         debug!("(adding default methods for trait) processing trait");
 
diff --git a/src/librustc/middle/typeck/collect.rs b/src/librustc/middle/typeck/collect.rs
index 68a0ca3890e..982a8d7d957 100644
--- a/src/librustc/middle/typeck/collect.rs
+++ b/src/librustc/middle/typeck/collect.rs
@@ -304,7 +304,7 @@ pub fn ensure_supertraits(ccx: @mut CrateCtxt,
                           rp: Option<ty::region_variance>,
                           trait_refs: &[@ast::trait_ref]) {
     let tcx = ccx.tcx;
-    if tcx.supertraits.contains_key_ref(&local_def(id)) { return; }
+    if tcx.supertraits.contains_key(&local_def(id)) { return; }
 
     let instantiated = dvec::DVec();
     for trait_refs.each |trait_ref| {
diff --git a/src/librustc/middle/typeck/infer/region_inference.rs b/src/librustc/middle/typeck/infer/region_inference.rs
index 60f5f440658..027b99cc421 100644
--- a/src/librustc/middle/typeck/infer/region_inference.rs
+++ b/src/librustc/middle/typeck/infer/region_inference.rs
@@ -1242,7 +1242,7 @@ impl RegionVarBindings {
 
         // It would be nice to write this using map():
         let mut edges = vec::with_capacity(num_edges);
-        for self.constraints.each_ref |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 e91fd1c31ca..5273dbd3049 100644
--- a/src/librustc/rustc.rc
+++ b/src/librustc/rustc.rc
@@ -177,7 +177,7 @@ Available lint options:
 
     let lint_dict = lint::get_lint_dict();
     let mut max_key = 0;
-    for lint_dict.each_key_ref |&k| { max_key = uint::max(k.len(), max_key); }
+    for lint_dict.each_key |&k| { max_key = uint::max(k.len(), max_key); }
     fn padded(max: uint, s: &str) -> ~str {
         str::from_bytes(vec::from_elem(max - s.len(), ' ' as u8)) + s
     }
@@ -186,7 +186,7 @@ Available lint options:
                      padded(max_key, ~"name"), ~"default", ~"meaning"));
     io::println(fmt!("    %s  %7.7s  %s\n",
                      padded(max_key, ~"----"), ~"-------", ~"-------"));
-    for lint_dict.each_ref |&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/oldmap.rs b/src/libstd/oldmap.rs
index ad7e8e50e38..cea6d17e35d 100644
--- a/src/libstd/oldmap.rs
+++ b/src/libstd/oldmap.rs
@@ -76,7 +76,7 @@ pub mod chained {
         FoundAfter(@Entry<K,V>, @Entry<K,V>)
     }
 
-    priv impl<K:Eq IterBytes Hash, V: Copy> T<K, V> {
+    priv impl<K:Eq IterBytes Hash, V> T<K, V> {
         pure fn search_rem(k: &K, h: uint, idx: uint,
                            e_root: @Entry<K,V>) -> SearchResult<K,V> {
             let mut e0 = e_root;
@@ -90,15 +90,13 @@ pub mod chained {
                   }
                   Some(e1) => {
                     comp += 1u;
-                    unsafe {
-                        if e1.hash == h && e1.key == *k {
-                            debug!("search_tbl: present, comp %u, \
-                                    hash %u, idx %u",
-                                   comp, h, idx);
-                            return FoundAfter(e0, e1);
-                        } else {
-                            e0 = e1;
-                        }
+                    if e1.hash == h && e1.key == *k {
+                        debug!(
+                            "search_tbl: present, comp %u, hash %u, idx %u",
+                            comp, h, idx);
+                        return FoundAfter(e0, e1);
+                    } else {
+                        e0 = e1;
                     }
                   }
                 }
@@ -114,14 +112,12 @@ pub mod chained {
                 return NotFound;
               }
               Some(e) => {
-                unsafe {
-                    if e.hash == h && e.key == *k {
-                        debug!("search_tbl: present, comp %u, hash %u, \
-                                idx %u", 1u, h, idx);
-                        return FoundFirst(idx, e);
-                    } else {
-                        return self.search_rem(k, h, idx, e);
-                    }
+                if e.hash == h && e.key == *k {
+                    debug!("search_tbl: present, comp %u, hash %u, \
+                           idx %u", 1u, h, idx);
+                    return FoundFirst(idx, e);
+                } else {
+                    return self.search_rem(k, h, idx, e);
                 }
               }
             }
@@ -172,8 +168,8 @@ pub mod chained {
         }
     }
 
-    impl<K:Eq IterBytes Hash Copy, V: Copy> T<K, V> {
-        pure fn contains_key_ref(&self, k: &K) -> bool {
+    impl<K: Eq IterBytes Hash, V> T<K, V> {
+        pure fn contains_key(&self, k: &K) -> bool {
             let hash = k.hash_keyed(0,0) as uint;
             match self.search_tbl(k, hash) {
               NotFound => false,
@@ -225,13 +221,43 @@ pub mod chained {
             }
         }
 
+        fn remove(k: &K) -> bool {
+            match self.search_tbl(k, k.hash_keyed(0,0) as uint) {
+              NotFound => false,
+              FoundFirst(idx, entry) => {
+                self.count -= 1u;
+                self.chains[idx] = entry.next;
+                true
+              }
+              FoundAfter(eprev, entry) => {
+                self.count -= 1u;
+                eprev.next = entry.next;
+                true
+              }
+            }
+        }
+
+        pure fn each(&self, blk: fn(key: &K, value: &V) -> bool) {
+            for self.each_entry |entry| {
+                if !blk(&entry.key, &entry.value) { break; }
+            }
+        }
+
+        pure fn each_key(&self, blk: fn(key: &K) -> bool) {
+            self.each(|k, _v| blk(k))
+        }
+
+        pure fn each_value(&self, blk: fn(value: &V) -> bool) {
+            self.each(|_k, v| blk(v))
+        }
+    }
+
+    impl<K: Eq IterBytes Hash Copy, V: Copy> T<K, V> {
         pure fn find(&self, k: &K) -> Option<V> {
-            unsafe {
-                match self.search_tbl(k, k.hash_keyed(0,0) as uint) {
-                  NotFound => None,
-                  FoundFirst(_, entry) => Some(entry.value),
-                  FoundAfter(_, entry) => Some(entry.value)
-                }
+            match self.search_tbl(k, k.hash_keyed(0,0) as uint) {
+              NotFound => None,
+              FoundFirst(_, entry) => Some(entry.value),
+              FoundAfter(_, entry) => Some(entry.value)
             }
         }
 
@@ -297,36 +323,6 @@ pub mod chained {
             }
             option::unwrap(move opt_v)
         }
-
-        fn remove(k: &K) -> bool {
-            match self.search_tbl(k, k.hash_keyed(0,0) as uint) {
-              NotFound => false,
-              FoundFirst(idx, entry) => {
-                self.count -= 1u;
-                self.chains[idx] = entry.next;
-                true
-              }
-              FoundAfter(eprev, entry) => {
-                self.count -= 1u;
-                eprev.next = entry.next;
-                true
-              }
-            }
-        }
-
-        pure fn each_ref(&self, blk: fn(key: &K, value: &V) -> bool) {
-            for self.each_entry |entry| {
-                if !blk(&entry.key, &entry.value) { break; }
-            }
-        }
-
-        pure fn each_key_ref(&self, blk: fn(key: &K) -> bool) {
-            self.each_ref(|k, _v| blk(k))
-        }
-
-        pure fn each_value_ref(&self, blk: fn(value: &V) -> bool) {
-            self.each_ref(|_k, v| blk(v))
-        }
     }
 
     impl<K:Eq IterBytes Hash Copy ToStr, V: ToStr Copy> T<K, V> {
@@ -362,9 +358,7 @@ pub mod chained {
 
     impl<K:Eq IterBytes Hash Copy, V: Copy> T<K, V>: ops::Index<K, V> {
         pure fn index(&self, k: K) -> V {
-            unsafe {
-                self.get(&k)
-            }
+            self.get(&k)
         }
     }
 
@@ -397,7 +391,7 @@ pub fn set_add<K:Eq IterBytes Hash Const Copy>(set: Set<K>, key: K) -> bool {
 /// Convert a set into a vector.
 pub pure fn vec_from_set<T:Eq IterBytes Hash Copy>(s: Set<T>) -> ~[T] {
     do vec::build_sized(s.len()) |push| {
-        for s.each_key_ref() |&k| {
+        for s.each_key() |&k| {
             push(k);
         }
     }
@@ -628,9 +622,9 @@ mod tests {
     fn test_contains_key() {
         let key = ~"k";
         let map = HashMap::<~str, ~str>();
-        assert (!map.contains_key_ref(&key));
+        assert (!map.contains_key(&key));
         map.insert(key, ~"val");
-        assert (map.contains_key_ref(&key));
+        assert (map.contains_key(&key));
     }
 
     #[test]
@@ -648,10 +642,10 @@ mod tests {
         let mut map = HashMap::<~str, ~str>();
         map.insert(key, ~"val");
         assert (map.len() == 1);
-        assert (map.contains_key_ref(&key));
+        assert (map.contains_key(&key));
         map.clear();
         assert (map.len() == 0);
-        assert (!map.contains_key_ref(&key));
+        assert (!map.contains_key(&key));
     }
 
     #[test]
diff --git a/src/libsyntax/attr.rs b/src/libsyntax/attr.rs
index c347c04641f..d258393e3b9 100644
--- a/src/libsyntax/attr.rs
+++ b/src/libsyntax/attr.rs
@@ -24,8 +24,7 @@ use core::either::Either;
 use core::either;
 use core::option;
 use core::vec;
-use std::oldmap::HashMap;
-use std::oldmap;
+use core::hashmap::linear::LinearSet;
 use std;
 
 /* Constructors */
@@ -358,16 +357,15 @@ pub fn find_inline_attr(attrs: &[ast::attribute]) -> inline_attr {
 
 pub fn require_unique_names(diagnostic: span_handler,
                             metas: &[@ast::meta_item]) {
-    let map = oldmap::HashMap();
+    let mut set = LinearSet::new();
     for metas.each |meta| {
         let name = get_meta_item_name(*meta);
 
         // FIXME: How do I silence the warnings? --pcw (#2619)
-        if map.contains_key_ref(&name) {
+        if !set.insert(name) {
             diagnostic.span_fatal(meta.span,
                                   fmt!("duplicate meta item `%s`", name));
         }
-        map.insert(name, ());
     }
 }
 
diff --git a/src/libsyntax/ext/tt/macro_parser.rs b/src/libsyntax/ext/tt/macro_parser.rs
index 9548db70b94..4b1194bb5f1 100644
--- a/src/libsyntax/ext/tt/macro_parser.rs
+++ b/src/libsyntax/ext/tt/macro_parser.rs
@@ -197,7 +197,7 @@ pub fn nameize(p_s: parse_sess, ms: ~[matcher], res: ~[@named_match])
           codemap::spanned {
                 node: match_nonterminal(bind_name, _, idx), span: sp
           } => {
-            if ret_val.contains_key_ref(&bind_name) {
+            if ret_val.contains_key(&bind_name) {
                 p_s.span_diagnostic.span_fatal(sp, ~"Duplicated bind name: "+
                                                *p_s.interner.get(bind_name))
             }
diff --git a/src/libsyntax/parse/common.rs b/src/libsyntax/parse/common.rs
index d82a5a18039..e0d53fadfa0 100644
--- a/src/libsyntax/parse/common.rs
+++ b/src/libsyntax/parse/common.rs
@@ -96,7 +96,7 @@ pub impl Parser {
 
     // A sanity check that the word we are asking for is a known keyword
     fn require_keyword(word: ~str) {
-        if !self.keywords.contains_key_ref(&word) {
+        if !self.keywords.contains_key(&word) {
             self.bug(fmt!("unknown keyword: %s", word));
         }
     }
@@ -120,7 +120,7 @@ pub impl Parser {
     fn is_any_keyword(tok: token::Token) -> bool {
         match tok {
           token::IDENT(sid, false) => {
-            self.keywords.contains_key_ref(self.id_to_str(sid))
+            self.keywords.contains_key(self.id_to_str(sid))
           }
           _ => false
         }
@@ -146,7 +146,7 @@ pub impl Parser {
     }
 
     fn is_strict_keyword(word: ~str) -> bool {
-        self.strict_keywords.contains_key_ref(&word)
+        self.strict_keywords.contains_key(&word)
     }
 
     fn check_strict_keywords() {
@@ -166,7 +166,7 @@ pub impl Parser {
     }
 
     fn is_reserved_keyword(word: ~str) -> bool {
-        self.reserved_keywords.contains_key_ref(&word)
+        self.reserved_keywords.contains_key(&word)
     }
 
     fn check_reserved_keywords() {
diff --git a/src/libsyntax/parse/obsolete.rs b/src/libsyntax/parse/obsolete.rs
index cdde542bb1f..9b2040fed1a 100644
--- a/src/libsyntax/parse/obsolete.rs
+++ b/src/libsyntax/parse/obsolete.rs
@@ -137,7 +137,7 @@ pub impl Parser {
                    desc: &str) {
         self.span_err(sp, fmt!("obsolete syntax: %s", kind_str));
 
-        if !self.obsolete_set.contains_key_ref(&kind) {
+        if !self.obsolete_set.contains_key(&kind) {
             self.sess.span_diagnostic.handler().note(fmt!("%s", desc));
             self.obsolete_set.insert(kind, ());
         }
diff --git a/src/libsyntax/parse/token.rs b/src/libsyntax/parse/token.rs
index 49de7264d2c..b8d756d893a 100644
--- a/src/libsyntax/parse/token.rs
+++ b/src/libsyntax/parse/token.rs
@@ -455,13 +455,13 @@ pub fn mk_fake_ident_interner() -> @ident_interner {
  */
 pub fn keyword_table() -> HashMap<~str, ()> {
     let keywords = HashMap();
-    for temporary_keyword_table().each_key_ref |&word| {
+    for temporary_keyword_table().each_key |&word| {
         keywords.insert(word, ());
     }
-    for strict_keyword_table().each_key_ref |&word| {
+    for strict_keyword_table().each_key |&word| {
         keywords.insert(word, ());
     }
-    for reserved_keyword_table().each_key_ref |&word| {
+    for reserved_keyword_table().each_key |&word| {
         keywords.insert(word, ());
     }
     keywords
diff --git a/src/test/bench/shootout-k-nucleotide-pipes.rs b/src/test/bench/shootout-k-nucleotide-pipes.rs
index 811f39e4343..62341f08ce3 100644
--- a/src/test/bench/shootout-k-nucleotide-pipes.rs
+++ b/src/test/bench/shootout-k-nucleotide-pipes.rs
@@ -49,7 +49,7 @@ fn sort_and_fmt(mm: HashMap<~[u8], uint>, total: uint) -> ~str {
    let mut pairs = ~[];
 
    // map -> [(k,%)]
-   for mm.each_ref |&key, &val| {
+   for mm.each |&key, &val| {
       pairs.push((key, pct(val, total)));
    }
 
diff --git a/src/test/bench/shootout-mandelbrot.rs b/src/test/bench/shootout-mandelbrot.rs
index 5888dab3bb9..b19454ec230 100644
--- a/src/test/bench/shootout-mandelbrot.rs
+++ b/src/test/bench/shootout-mandelbrot.rs
@@ -134,7 +134,7 @@ fn writer(path: ~str, pport: pipes::Port<Line>, size: uint)
             done += 1_u;
             let mut prev = done;
             while prev <= i {
-                if lines.contains_key_ref(&prev) {
+                if lines.contains_key(&prev) {
                     debug!("WS %u", prev);
                     cout.write(lines.get(&prev));
                     done += 1_u;