diff --git a/src/libcargo/cargo.rc b/src/libcargo/cargo.rc
index 52addaa4fec1..d0783911f72b 100644
--- a/src/libcargo/cargo.rc
+++ b/src/libcargo/cargo.rc
@@ -833,7 +833,7 @@ pub fn rustc_sysroot() -> ~str {
     }
 }
 
-pub fn install_source(c: &Cargo, path: &Path) {
+pub fn install_source(c: &mut Cargo, path: &Path) {
     debug!("source: %s", path.to_str());
     os::change_dir(path);
 
@@ -872,7 +872,8 @@ pub fn install_source(c: &Cargo, path: &Path) {
     }
 }
 
-pub fn install_git(c: &Cargo, wd: &Path, url: ~str, reference: Option<~str>) {
+pub fn install_git(c: &mut Cargo, wd: &Path, url: ~str,
+                   reference: Option<~str>) {
     run::program_output(~"git", ~[~"clone", url, wd.to_str()]);
     if reference.is_some() {
         let r = reference.get();
@@ -883,7 +884,7 @@ pub fn install_git(c: &Cargo, wd: &Path, url: ~str, reference: Option<~str>) {
     install_source(c, wd);
 }
 
-pub fn install_curl(c: &Cargo, wd: &Path, url: ~str) {
+pub fn install_curl(c: &mut Cargo, wd: &Path, url: ~str) {
     let tarpath = wd.push("pkg.tar");
     let p = run::program_output(~"curl", ~[~"-f", ~"-s", ~"-o",
                                          tarpath.to_str(), url]);
@@ -896,14 +897,14 @@ pub fn install_curl(c: &Cargo, wd: &Path, url: ~str) {
     install_source(c, wd);
 }
 
-pub fn install_file(c: &Cargo, wd: &Path, path: &Path) {
+pub fn install_file(c: &mut Cargo, wd: &Path, path: &Path) {
     run::program_output(~"tar", ~[~"-x", ~"--strip-components=1",
                                   ~"-C", wd.to_str(),
                                   ~"-f", path.to_str()]);
     install_source(c, wd);
 }
 
-pub fn install_package(c: &Cargo, src: ~str, wd: &Path, pkg: Package) {
+pub fn install_package(c: &mut Cargo, src: ~str, wd: &Path, pkg: Package) {
     let url = copy pkg.url;
     let method = match pkg.method {
         ~"git" => ~"git",
@@ -930,7 +931,7 @@ pub fn cargo_suggestion(c: &Cargo, fallback: fn()) {
     fallback();
 }
 
-pub fn install_uuid(c: &Cargo, wd: &Path, uuid: ~str) {
+pub fn install_uuid(c: &mut Cargo, wd: &Path, uuid: ~str) {
     let mut ps = ~[];
     for_each_package(c, |s, p| {
         if p.uuid == uuid {
@@ -954,7 +955,7 @@ pub fn install_uuid(c: &Cargo, wd: &Path, uuid: ~str) {
     }
 }
 
-pub fn install_named(c: &Cargo, wd: &Path, name: ~str) {
+pub fn install_named(c: &mut Cargo, wd: &Path, name: ~str) {
     let mut ps = ~[];
     for_each_package(c, |s, p| {
         if p.name == name {
@@ -978,7 +979,8 @@ pub fn install_named(c: &Cargo, wd: &Path, name: ~str) {
     }
 }
 
-pub fn install_uuid_specific(c: &Cargo, wd: &Path, src: ~str, uuid: ~str) {
+pub fn install_uuid_specific(c: &mut Cargo, wd: &Path, src: ~str,
+                             uuid: ~str) {
     match c.sources.find(src) {
         Some(s) => {
             for s.packages.each |p| {
@@ -993,7 +995,8 @@ pub fn install_uuid_specific(c: &Cargo, wd: &Path, src: ~str, uuid: ~str) {
     error(~"can't find package: " + src + ~"/" + uuid);
 }
 
-pub fn install_named_specific(c: &Cargo, wd: &Path, src: ~str, name: ~str) {
+pub fn install_named_specific(c: &mut Cargo, wd: &Path, src: ~str,
+                              name: ~str) {
     match c.sources.find(src) {
         Some(s) => {
             for s.packages.each |p| {
@@ -1060,7 +1063,7 @@ pub fn cmd_uninstall(c: &Cargo) {
     }
 }
 
-pub fn install_query(c: &Cargo, wd: &Path, target: ~str) {
+pub fn install_query(c: &mut Cargo, wd: &Path, target: ~str) {
     match c.dep_cache.find(target) {
         Some(inst) => {
             if inst {
@@ -1112,10 +1115,7 @@ pub fn install_query(c: &Cargo, wd: &Path, target: ~str) {
     // a bit of a hack. It should be cleaned up in the future.
 
     if target == c.current_install {
-        for c.dep_cache.each |k, _v| {
-            c.dep_cache.remove(k);
-        }
-
+        c.dep_cache.clear();
         c.current_install = ~"";
     }
 }
@@ -1128,7 +1128,7 @@ pub fn get_temp_workdir(c: &Cargo) -> Path {
     }
 }
 
-pub fn cmd_install(c: &Cargo) {
+pub fn cmd_install(c: &mut Cargo) {
     unsafe {
         let wd = get_temp_workdir(c);
 
@@ -1636,7 +1636,7 @@ pub fn dump_sources(c: &Cargo) {
         result::Ok(writer) => {
             let mut hash = ~LinearMap::new();
 
-            for c.sources.each |k, v| {
+            for c.sources.each_ref |&k, &v| {
                 let mut chash = ~LinearMap::new();
 
                 chash.insert(~"url", json::String(v.url));
@@ -1967,7 +1967,7 @@ pub fn main() {
 
     match o.free[1] {
         ~"init" => cmd_init(&c),
-        ~"install" => cmd_install(&c),
+        ~"install" => cmd_install(&mut c),
         ~"uninstall" => cmd_uninstall(&c),
         ~"list" => cmd_list(&c),
         ~"search" => cmd_search(&c),
diff --git a/src/librustc/metadata/cstore.rs b/src/librustc/metadata/cstore.rs
index 541ea0e40f54..c8a1a619436b 100644
--- a/src/librustc/metadata/cstore.rs
+++ b/src/librustc/metadata/cstore.rs
@@ -99,7 +99,7 @@ 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 p(cstore).metas.each |k,v| { i(k, v);};
+    for p(cstore).metas.each_ref |&k, &v| { i(k, v);};
 }
 
 pub fn add_used_crate_file(cstore: CStore, lib: &Path) {
diff --git a/src/librustc/middle/lang_items.rs b/src/librustc/middle/lang_items.rs
index 24f6ec71788f..3eb65505e646 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 |key, item_ref| {
+        for self.item_refs.each_ref |&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 133eb59d0cfa..0dc7a746e9e8 100644
--- a/src/librustc/middle/lint.rs
+++ b/src/librustc/middle/lint.rs
@@ -400,7 +400,9 @@ pub fn build_settings_crate(sess: session::Session, crate: @ast::crate) {
                     sess: sess});
 
     // Install defaults.
-    for cx.dict.each |_k, spec| { cx.set_level(spec.lint, spec.default); }
+    for cx.dict.each_value_ref |&spec| {
+        cx.set_level(spec.lint, spec.default);
+    }
 
     // Install command-line options, overriding defaults.
     for sess.opts.lint_opts.each |pair| {
diff --git a/src/librustc/middle/region.rs b/src/librustc/middle/region.rs
index e83fe9f0f99c..4602d2aff4ee 100644
--- a/src/librustc/middle/region.rs
+++ b/src/librustc/middle/region.rs
@@ -833,7 +833,7 @@ pub fn determine_rp_in_crate(sess: Session,
 
     debug!("%s", {
         debug!("Region variance results:");
-        for cx.region_paramd_items.each |key, value| {
+        for cx.region_paramd_items.each_ref |&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 83fc335481c7..9fbe378a4a45 100644
--- a/src/librustc/middle/resolve.rs
+++ b/src/librustc/middle/resolve.rs
@@ -1913,7 +1913,7 @@ pub impl Resolver {
                self.module_to_str(module_));
         self.resolve_imports_for_module(module_);
 
-        for module_.children.each |_name, child_node| {
+        for module_.children.each_value_ref |&child_node| {
             match child_node.get_module_if_available() {
                 None => {
                     // Nothing to do.
@@ -1924,7 +1924,7 @@ pub impl Resolver {
             }
         }
 
-        for module_.anonymous_children.each |_block_id, child_module| {
+        for module_.anonymous_children.each_value_ref |&child_module| {
             self.resolve_imports_for_module_subtree(child_module);
         }
     }
@@ -2430,8 +2430,8 @@ pub impl Resolver {
         assert containing_module.glob_count == 0;
 
         // Add all resolved imports from the containing module.
-        for containing_module.import_resolutions.each
-                |ident, target_import_resolution| {
+        for containing_module.import_resolutions.each_ref
+                |&ident, &target_import_resolution| {
 
             debug!("(resolving glob import) writing module resolution \
                     %? into `%s`",
@@ -2480,7 +2480,7 @@ pub impl Resolver {
         }
 
         // Add all children from the containing module.
-        for containing_module.children.each |ident, name_bindings| {
+        for containing_module.children.each_ref |&ident, &name_bindings| {
             let mut dest_import_resolution;
             match module_.import_resolutions.find(ident) {
                 None => {
@@ -3148,7 +3148,7 @@ pub impl Resolver {
         }
 
         // Descend into children and anonymous children.
-        for module_.children.each |_name, child_node| {
+        for module_.children.each_value_ref |&child_node| {
             match child_node.get_module_if_available() {
                 None => {
                     // Continue.
@@ -3159,7 +3159,7 @@ pub impl Resolver {
             }
         }
 
-        for module_.anonymous_children.each |_name, module_| {
+        for module_.anonymous_children.each_value_ref |&module_| {
             self.report_unresolved_imports(module_);
         }
     }
@@ -3204,7 +3204,7 @@ pub impl Resolver {
 
         self.record_exports_for_module(module_);
 
-        for module_.children.each |_ident, child_name_bindings| {
+        for module_.children.each_value_ref |&child_name_bindings| {
             match child_name_bindings.get_module_if_available() {
                 None => {
                     // Nothing to do.
@@ -3215,7 +3215,7 @@ pub impl Resolver {
             }
         }
 
-        for module_.anonymous_children.each |_node_id, child_module| {
+        for module_.anonymous_children.each_value_ref |&child_module| {
             self.record_exports_for_module_subtree(child_module);
         }
     }
@@ -4068,7 +4068,7 @@ 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_ref |&key, &binding_0| {
                 match map_i.find(key) {
                   None => {
                     self.session.span_err(
@@ -4089,7 +4089,7 @@ pub impl Resolver {
                 }
             }
 
-            for map_i.each |key, binding| {
+            for map_i.each_ref |&key, &binding| {
                 if !map_0.contains_key_ref(&key) {
                     self.session.span_err(
                         binding.span,
@@ -5001,7 +5001,7 @@ pub impl Resolver {
             }
 
             // Look for trait children.
-            for search_module.children.each |_name, child_name_bindings| {
+            for search_module.children.each_value_ref |&child_name_bindings| {
                 match child_name_bindings.def_for_namespace(TypeNS) {
                     Some(def) => {
                         match def {
@@ -5021,8 +5021,8 @@ pub impl Resolver {
             }
 
             // Look for imports.
-            for search_module.import_resolutions.each
-                    |_ident, import_resolution| {
+            for search_module.import_resolutions.each_value_ref
+                    |&import_resolution| {
 
                 match import_resolution.target_for_namespace(TypeNS) {
                     None => {
@@ -5184,7 +5184,7 @@ pub impl Resolver {
 
         self.check_for_unused_imports_in_module(module_);
 
-        for module_.children.each |_ident, child_name_bindings| {
+        for module_.children.each_value_ref |&child_name_bindings| {
             match (*child_name_bindings).get_module_if_available() {
                 None => {
                     // Nothing to do.
@@ -5196,13 +5196,13 @@ pub impl Resolver {
             }
         }
 
-        for module_.anonymous_children.each |_node_id, child_module| {
+        for module_.anonymous_children.each_value_ref |&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 |_name, import_resolution| {
+        for module_.import_resolutions.each_value_ref |&import_resolution| {
             if !import_resolution.used {
                 match self.unused_import_lint_level {
                     warn => {
@@ -5261,12 +5261,12 @@ pub impl Resolver {
         debug!("Dump of module `%s`:", self.module_to_str(module_));
 
         debug!("Children:");
-        for module_.children.each |name, _child| {
+        for module_.children.each_key_ref |&name| {
             debug!("* %s", self.session.str_of(name));
         }
 
         debug!("Import resolutions:");
-        for module_.import_resolutions.each |name, import_resolution| {
+        for module_.import_resolutions.each_ref |&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 894d0a0c7991..02c237fcef3e 100644
--- a/src/librustc/middle/trans/base.rs
+++ b/src/librustc/middle/trans/base.rs
@@ -2806,7 +2806,7 @@ 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 |key, val| {
+    for ccx.module_data.each_ref |&key, &val| {
         let elt = C_struct(~[p2i(ccx, C_cstr(ccx, key)),
                             p2i(ccx, val)]);
         elts.push(elt);
@@ -3087,7 +3087,7 @@ 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_ref |&k, &v| {
                 io::println(fmt!("%-7u %s", v, k));
             }
         }
diff --git a/src/librustc/middle/trans/glue.rs b/src/librustc/middle/trans/glue.rs
index 0c93ca18c3b8..849a718a52e9 100644
--- a/src/librustc/middle/trans/glue.rs
+++ b/src/librustc/middle/trans/glue.rs
@@ -757,7 +757,7 @@ 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 |_key, val| {
+    for ccx.tydescs.each_value_ref |&val| {
         let glue_fn_ty = T_ptr(T_generic_glue_fn(ccx));
         let ti = val;
 
diff --git a/src/librustc/rustc.rc b/src/librustc/rustc.rc
index e29fcf69ef93..99203d9d6a40 100644
--- a/src/librustc/rustc.rc
+++ b/src/librustc/rustc.rc
@@ -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 |k, v| {
+    for lint_dict.each_ref |&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 7fd8aabc2fb3..5ab0bd682997 100644
--- a/src/libstd/oldmap.rs
+++ b/src/libstd/oldmap.rs
@@ -316,10 +316,6 @@ pub mod chained {
             }
         }
 
-        pure fn each(blk: fn(key: K, value: V) -> bool) {
-            self.each_ref(|k, v| blk(*k, *v))
-        }
-
         pure fn each_ref(blk: fn(key: &K, value: &V) -> bool) {
             for self.each_entry |entry| {
                 if !blk(&entry.key, &entry.value) { break; }
diff --git a/src/test/bench/shootout-k-nucleotide-pipes.rs b/src/test/bench/shootout-k-nucleotide-pipes.rs
index 2ffbe02840e1..0f4f22196ce6 100644
--- a/src/test/bench/shootout-k-nucleotide-pipes.rs
+++ b/src/test/bench/shootout-k-nucleotide-pipes.rs
@@ -49,10 +49,9 @@ fn sort_and_fmt(mm: HashMap<~[u8], uint>, total: uint) -> ~str {
    let mut pairs = ~[];
 
    // map -> [(k,%)]
-   mm.each(fn&(key: ~[u8], val: uint) -> bool {
+   for mm.each_ref |&key, &val| {
       pairs.push((key, pct(val, total)));
-      return true;
-   });
+   }
 
    let pairs_sorted = sortKV(pairs);