diff --git a/lib/elixir/include/elixir.hrl b/lib/elixir/include/elixir.hrl
index db6db735a0..e38b3f0e5d 100644
--- a/lib/elixir/include/elixir.hrl
+++ b/lib/elixir/include/elixir.hrl
@@ -22,7 +22,7 @@
   quote_vars=[],                                 %% a dict of all quoted variables
   clause_vars=nil,                               %% a dict of all variables defined in a particular clause
   extra_guards=nil,                              %% extra guards from args expansion
-  counter=0,                                     %% a counter for the variables defined
+  counter=[],                                    %% a counter for the variables defined
   file=(<<"nofile">>),                           %% the current scope filename
   local=nil,                                     %% the scope to evaluate local functions against
   aliases=[],                                    %% an orddict with aliases by new -> old names
diff --git a/lib/elixir/lib/kernel/parallel_require.ex b/lib/elixir/lib/kernel/parallel_require.ex
index 566acdafff..0f7c8bf5ef 100644
--- a/lib/elixir/lib/kernel/parallel_require.ex
+++ b/lib/elixir/lib/kernel/parallel_require.ex
@@ -27,10 +27,9 @@ defmodule Kernel.ParallelRequire do
 
     child  = spawn_link fn ->
       try do
-        new    = Code.require_file(h)
-        result = (new || []) ++ result
+        new = Code.require_file(h)
         callback.(h)
-        parent <- { :required, self }
+        parent <- { :required, self, new }
       catch
         kind, reason ->
           parent <- { :failure, self, kind, reason, System.stacktrace }
@@ -42,8 +41,8 @@ defmodule Kernel.ParallelRequire do
 
   defp wait_for_messages(files, waiting, callback, result) do
     receive do
-      { :required, child } ->
-        spawn_requires(files, List.delete(waiting, child), callback, result)
+      { :required, child, new } ->
+        spawn_requires(files, List.delete(waiting, child), callback, (new || []) ++ result)
       { :failure, _child, kind, reason, stacktrace } ->
         :erlang.raise(kind, reason, stacktrace)
     end
diff --git a/lib/elixir/lib/list.ex b/lib/elixir/lib/list.ex
index 867229a449..6f29ac81eb 100644
--- a/lib/elixir/lib/list.ex
+++ b/lib/elixir/lib/list.ex
@@ -271,7 +271,7 @@ defmodule List do
   def range(first, last, step // nil)
 
   def range(first, last, step) when is_integer(first) and is_integer(last) and first <= last do
-    step = case step do
+    case step do
       nil ->
         :lists.seq(first, last, 1)
       x when x < 0 ->
@@ -282,7 +282,7 @@ defmodule List do
   end
 
   def range(first, last, step) when is_integer(first) and is_integer(last) and first > last do
-    step = case step do
+    case step do
       nil ->
         :lists.seq(first, last, -1)
       x when x > 0 ->
diff --git a/lib/elixir/src/elixir.erl b/lib/elixir/src/elixir.erl
index 16d944dcce..751d9a45ab 100644
--- a/lib/elixir/src/elixir.erl
+++ b/lib/elixir/src/elixir.erl
@@ -104,7 +104,7 @@ eval_forms(Tree, Binding, RawScope) ->
     temp_vars=[],
     quote_vars=[],
     clause_vars=nil,
-    counter=0
+    counter=[]
   },
   { ParseTree, NewScope } = elixir_translator:translate(Tree, Scope),
   case ParseTree of
@@ -125,9 +125,10 @@ binding_dict([], Dict) -> Dict.
 
 final_binding(Binding, Vars) -> final_binding(Binding, [], Binding, Vars).
 final_binding([{Var,_}|T], Acc, Binding, Vars) ->
-  case atom_to_list(Var) of
-    "_@" ++ _ -> final_binding(T, Acc, Binding, Vars);
-    _ ->
+  case lists:member($@, atom_to_list(Var)) of
+    true  ->
+      final_binding(T, Acc, Binding, Vars);
+    false ->
       RealName = orddict:fetch(Var, Vars),
       RealValue = proplists:get_value(RealName, Binding, nil),
       final_binding(T, [{Var, RealValue}|Acc], Binding, Vars)
diff --git a/lib/elixir/src/elixir_def_defaults.erl b/lib/elixir/src/elixir_def_defaults.erl
index 58217dc238..8ffd828173 100644
--- a/lib/elixir/src/elixir_def_defaults.erl
+++ b/lib/elixir/src/elixir_def_defaults.erl
@@ -15,8 +15,7 @@ unpack_each(Kind, Name, [{'//', Line, [Expr, _]}|T] = List, Acc, Clauses, S) ->
   Base = build_match(Acc, Line, []),
   { Args, Invoke } = extract_defaults(List, Line, length(Base), [], []),
 
-  SM = S#elixir_scope{counter=length(Base)},
-  { DefArgs, SA }   = elixir_clauses:assigns(fun elixir_translator:translate/2, Base ++ Args, SM),
+  { DefArgs, SA }   = elixir_clauses:assigns(fun elixir_translator:translate/2, Base ++ Args, S),
   { InvokeArgs, _ } = elixir_translator:translate_args(Base ++ Invoke, SA),
 
   Call = { call, Line,
@@ -39,7 +38,7 @@ extract_defaults([{'//', _, [_Expr, Default]}|T], Line, Counter, NewArgs, NewInv
   extract_defaults(T, Line, Counter, NewArgs, [Default|NewInvoke]);
 
 extract_defaults([_|T], Line, Counter, NewArgs, NewInvoke) ->
-  H = { ?ELIXIR_ATOM_CONCAT(["_@", Counter]), Line, nil },
+  H = { ?ELIXIR_ATOM_CONCAT(["_@D", Counter]), Line, nil },
   extract_defaults(T, Line, Counter + 1, [H|NewArgs], [H|NewInvoke]);
 
 extract_defaults([], _Line, _Counter, NewArgs, NewInvoke) ->
@@ -50,7 +49,7 @@ extract_defaults([], _Line, _Counter, NewArgs, NewInvoke) ->
 build_match([], _Line, Acc) -> Acc;
 
 build_match([_|T], Line, Acc) ->
-  Var = { ?ELIXIR_ATOM_CONCAT(["_@", length(T)]), Line, nil },
+  Var = { ?ELIXIR_ATOM_CONCAT(["_@D", length(T)]), Line, nil },
   build_match(T, Line, [Var|Acc]).
 
 % Given the invoked function name based on the kind
diff --git a/lib/elixir/src/elixir_errors.erl b/lib/elixir/src/elixir_errors.erl
index 1397703604..58b37f98fc 100644
--- a/lib/elixir/src/elixir_errors.erl
+++ b/lib/elixir/src/elixir_errors.erl
@@ -106,6 +106,11 @@ handle_file_warning(_, File, {Line,erl_lint,{undefined_behaviour,Module}}) ->
   io:format(file_format(Line, File, Message));
 
 %% Default behavior
+handle_file_warning(_, File, {Line,erl_lint,{unused_var,Var}}) ->
+  List    = lists:takewhile(fun(X) -> X /= $@ end, atom_to_list(Var)),
+  Message = format_error(erl_lint, { unused_var, list_to_atom(List) }),
+  io:format(file_format(Line, File, Message));
+
 handle_file_warning(_, File, {Line,Module,Desc}) ->
   Message = format_error(Module, Desc),
   io:format(file_format(Line, File, Message)).
diff --git a/lib/elixir/src/elixir_scope.erl b/lib/elixir/src/elixir_scope.erl
index 1b1db4957e..7709f79f0f 100644
--- a/lib/elixir/src/elixir_scope.erl
+++ b/lib/elixir/src/elixir_scope.erl
@@ -1,8 +1,10 @@
+
 %% Convenience functions used to manipulate scope
 %% and its variables.
 -module(elixir_scope).
 -export([translate_var/4,
   build_erl_var/2, build_ex_var/2,
+  build_erl_var/3, build_ex_var/3,
   serialize/1, deserialize/1, deserialize/2,
   to_erl_env/1, to_ex_env/1, filename/1,
   umergev/2, umergec/2, merge_clause_vars/2
@@ -24,9 +26,11 @@ translate_var(Line, Name, Kind, S) ->
             { true, { ok, Kind } } ->
               { {var, Line, orddict:fetch(Name, Vars) }, S };
             { Else, _ } ->
-              { NewVar, NS } = case Else or S#elixir_scope.noname of
-                true -> build_erl_var(Line, S);
-                false -> { {var, Line, Name}, S }
+              { NewVar, NS } = if
+                Else -> build_erl_var(Line, Name, S);
+                Kind == quoted -> build_erl_var(Line, S);
+                S#elixir_scope.noname -> build_erl_var(Line, Name, S);
+                true -> { {var, Line, Name}, S }
               end,
               RealName = element(3, NewVar),
               ClauseVars = S#elixir_scope.clause_vars,
@@ -49,14 +53,24 @@ translate_var(Line, Name, Kind, S) ->
 
 % Handle variables translation
 
-build_erl_var(Line, #elixir_scope{counter=Counter} = S) ->
-  NS = S#elixir_scope{counter=Counter+1},
-  Var = { var, Line, ?ELIXIR_ATOM_CONCAT(["_@", Counter]) },
+build_ex_var(Line, S)  -> build_ex_var(Line, "_", '', S).
+build_erl_var(Line, S) -> build_erl_var(Line, "_", '', S).
+
+build_ex_var(Line, Key, S)  -> build_ex_var(Line, "", Key, S).
+build_erl_var(Line, Key, S) -> build_erl_var(Line, "", Key, S).
+
+build_var_counter(Key, #elixir_scope{counter=Counter} = S) ->
+  New = orddict:update_counter(Key, 1, Counter),
+  { orddict:fetch(Key, New), S#elixir_scope{counter=New} }.
+
+build_erl_var(Line, Prefix, Key, S) ->
+  { Counter, NS } = build_var_counter(Key, S),
+  Var = { var, Line, ?ELIXIR_ATOM_CONCAT([Prefix, Key, "@", Counter]) },
   { Var, NS }.
 
-build_ex_var(Line, #elixir_scope{counter=Counter} = S) ->
-  NS = S#elixir_scope{counter=Counter+1},
-  Var = { ?ELIXIR_ATOM_CONCAT(["_@", Counter]), Line, nil },
+build_ex_var(Line, Prefix, Key, S) ->
+  { Counter, NS } = build_var_counter(Key, S),
+  Var = { ?ELIXIR_ATOM_CONCAT([Prefix, Key, "@", Counter]), Line, nil },
   { Var, NS }.
 
 % Handle Macro.Env conversion
@@ -97,7 +111,7 @@ deserialize({ File, Functions, CheckClauses, Requires, Macros, Aliases, Schedule
     aliases=Aliases,
     scheduled=Scheduled,
     vars=orddict:from_list(Vars),
-    counter=length(Vars)
+    counter=[{'',length(Vars)}]
   }.
 
 % Receives two scopes and return a new scope based on the second
@@ -141,10 +155,7 @@ clause_var_merger({ Var, _ }, K1, K2) ->
 var_merger(Var, Var, K2) -> K2;
 var_merger(Var, K1, Var) -> K1;
 var_merger(_Var, K1, K2) ->
-  V1 = var_number(atom_to_list(K1)),
-  V2 = var_number(atom_to_list(K2)),
-  if V1 > V2 -> K1;
-     true -> K2
+  case atom_to_list(K1) > atom_to_list(K2) of
+    true  -> K1;
+    false -> K2
   end.
-
-var_number([_,_|T]) -> list_to_integer(T).
\ No newline at end of file
diff --git a/lib/elixir/test/elixir/uri_test.exs b/lib/elixir/test/elixir/uri_test.exs
index 0a7b0987e6..6e888d579f 100644
--- a/lib/elixir/test/elixir/uri_test.exs
+++ b/lib/elixir/test/elixir/uri_test.exs
@@ -1,3 +1,5 @@
+Code.require_file "../test_helper.exs", __FILE__
+
 defmodule URITest do
   use ExUnit.Case, async: true
 
diff --git a/lib/ex_unit/lib/ex_unit/assertions.ex b/lib/ex_unit/lib/ex_unit/assertions.ex
index 48a5d2b041..3ff544cc1c 100644
--- a/lib/ex_unit/lib/ex_unit/assertions.ex
+++ b/lib/ex_unit/lib/ex_unit/assertions.ex
@@ -69,15 +69,8 @@ defmodule ExUnit.Assertions do
     quote do: (var!(op) == :! or var!(op) == :not)
   end
 
-  defp translate_assertion({ :=, _, [expected, received] }, _else) do
-    quote do
-      unquote(expected) = try do
-        unquote(expected) = unquote(received)
-      rescue
-        x in [MatchError] ->
-          raise ExUnit.AssertionError, message: x.message
-      end
-    end
+  defp translate_assertion({ :=, _, [_, _] } = expr, _else) do
+    expr
   end
 
   defp translate_assertion({ :==, _, [left, right] }, _else) do
@@ -132,7 +125,7 @@ defmodule ExUnit.Assertions do
         unquote(expected) = x = unquote(received)
         flunk "Unexpected right side #{inspect x} match"
       rescue
-        x in [MatchError] -> true
+        _ in [MatchError] -> true
       end
     end
   end
diff --git a/lib/ex_unit/test/ex_unit/assertions_test.exs b/lib/ex_unit/test/ex_unit/assertions_test.exs
index baec9b3b1c..40af2d24cc 100644
--- a/lib/ex_unit/test/ex_unit/assertions_test.exs
+++ b/lib/ex_unit/test/ex_unit/assertions_test.exs
@@ -75,16 +75,6 @@ defmodule ExUnit.AssertionsTest do
     { 2, 1 } = (assert { 2, 1 } = Value.tuple)
   end
 
-  test :assert_match_when_different do
-    try do
-      assert {_, 2} = Value.tuple
-      raise "failed"
-    rescue
-      error in [ExUnit.AssertionError] ->
-        "no match of right hand side value: {2,1}" = error.message
-    end
-  end
-
   test :assert_received do
     self <- :hello
     :hello = assert_received :hello