Rewrite done

Author: josevalim

lib/elixir/lib/module/types.ex

@@ -52,14 +52,9 @@ defmodule Module.Types do
   end
 
   defp warnings_from_clause(meta, args, guards, body, stack, context) do
-    case Pattern.of_head(args, guards, meta, stack, context) do
-      {:ok, _types, context} ->
-        {_type, context} = Expr.of_expr(body, stack, context)
-        context.warnings
-
-      {:error, context} ->
-        context.warnings
-    end
+    {_types, context} = Pattern.of_head(args, guards, meta, stack, context)
+    {_type, context} = Expr.of_expr(body, stack, context)
+    context.warnings
   end
 
   @doc false

lib/elixir/lib/module/types/expr.ex

@@ -358,11 +358,8 @@ defmodule Module.Types.Expr do
   defp for_clause({:<-, meta, [left, expr]}, stack, context) do
     {pattern, guards} = extract_head([left])
     {_expr_type, context} = of_expr(expr, stack, context)
-
-    case Pattern.of_head([pattern], guards, meta, stack, context) do
-      {:ok, _, context} -> context
-      {:error, context} -> context
-    end
+    {[_type], context} = Pattern.of_head([pattern], guards, meta, stack, context)
+    context
   end
 
   defp for_clause({:<<>>, _, [{:<-, meta, [left, right]}]}, stack, context) do
@@ -398,14 +395,9 @@ defmodule Module.Types.Expr do
   defp with_clause({:<-, meta, [left, expr]}, stack, context) do
     {pattern, guards} = extract_head([left])
 
-    case Pattern.of_head([pattern], guards, meta, stack, context) do
-      {:ok, _, context} ->
-        {_expr_type, context} = of_expr(expr, stack, context)
-        context
-
-      {:error, context} ->
-        context
-    end
+    {[_type], context} = Pattern.of_head([pattern], guards, meta, stack, context)
+    {_expr_type, context} = of_expr(expr, stack, context)
+    context
   end
 
   defp with_clause(expr, stack, context) do
@@ -443,14 +435,9 @@ defmodule Module.Types.Expr do
     Enum.reduce(clauses, context, fn {:->, meta, [head, body]}, context ->
       {patterns, guards} = extract_head(head)
 
-      case Pattern.of_head(patterns, guards, meta, stack, context) do
-        {:ok, _, context} ->
-          {_, context} = of_expr(body, stack, context)
-          context
-
-        {:error, context} ->
-          context
-      end
+      {_types, context} = Pattern.of_head(patterns, guards, meta, stack, context)
+      {_, context} = of_expr(body, stack, context)
+      context
     end)
   end
 

lib/elixir/lib/module/types/pattern.ex

@@ -34,7 +34,7 @@ defmodule Module.Types.Pattern do
 
     {_trees, types, context} = of_pattern_args(patterns, expected_types, stack, context)
     {_, context} = Enum.map_reduce(guards, context, &of_guard(&1, @guard, &1, stack, &2))
-    {:ok, types, context}
+    {types, context}
   end
 
   defp of_pattern_args([], [], _stack, context) do

lib/elixir/test/elixir/module/types/type_helper.exs

@@ -131,11 +131,8 @@ defmodule TypeHelper do
 
   def __typecheck__(patterns, guards, body) do
     stack = new_stack()
-
-    case Pattern.of_head(patterns, guards, [], stack, new_context()) do
-      {:ok, _types, context} -> Expr.of_expr(body, stack, context)
-      {:error, context} -> {Module.Types.Descr.dynamic(), context}
-    end
+    {_types, context} = Pattern.of_head(patterns, guards, [], stack, new_context())
+    Expr.of_expr(body, stack, context)
   end
 
   defp expand_and_unpack(patterns, guards, body, env) do