Use :lists.member as it uses === and not ==

Author: José Valim

lib/elixir/lib/hash_set.ex

@@ -38,8 +38,7 @@ defmodule HashSet do
   import Bitwise
 
   @compile :inline_list_funcs
-  @compile { :inline, bucket_hash: 1, bucket_index: 1, bucket_nth_index: 2,
-                      bucket_next: 1, bucket_member?: 2 }
+  @compile { :inline, bucket_hash: 1, bucket_index: 1, bucket_nth_index: 2, bucket_next: 1 }
 
   @doc """
   Creates a new empty set.
@@ -189,11 +188,11 @@ defmodule HashSet do
   end
 
   defp set_member?(ordered(bucket: bucket), member) do
-    bucket_member?(member, bucket)
+    :lists.member(member, bucket)
   end
 
   defp set_member?(trie(root: root, depth: depth), member) do
-    bucket_member?(member, node_bucket(root, depth, bucket_hash(member)))
+    :lists.member(member, node_bucket(root, depth, bucket_hash(member)))
   end
 
   defp set_delete(ordered(bucket: bucket, size: size) = set, member) do
@@ -261,10 +260,6 @@ defmodule HashSet do
 
   ## Bucket helpers
 
-  defp bucket_member?(k, [k|_]), do: true
-  defp bucket_member?(k, [_|t]), do: bucket_member?(k, t)
-  defp bucket_member?(_k, []),   do: false
-
   defp bucket_filter([e|bucket], fun, acc, count) do
     case fun.(e) do
       true  -> bucket_filter(bucket, fun, [e|acc], count)

lib/elixir/lib/list_dict.ex

@@ -94,7 +94,7 @@ defmodule ListDict do
     acc = { [], [] }
 
     {take, drop} = Enum.reduce dict, acc, fn({ k, v }, { take, drop }) ->
-      if any_key?(k, keys) do
+      if :lists.member(k, keys) do
         { [{k, v}|take], drop }
       else
         { take, [{k, v}|drop] }
@@ -105,11 +105,11 @@ defmodule ListDict do
   end
 
   def take(dict, keys) do
-    lc { k, _ } = tuple inlist dict, any_key?(k, keys), do: tuple
+    lc { k, _ } = tuple inlist dict, :lists.member(k, keys), do: tuple
   end
 
   def drop(dict, keys) do
-    lc { k, _ } = tuple inlist dict, not any_key?(k, keys), do: tuple
+    lc { k, _ } = tuple inlist dict, not :lists.member(k, keys), do: tuple
   end
 
   def update!([{key, value}|dict], key, fun) do
@@ -143,8 +143,4 @@ defmodule ListDict do
   end
 
   def to_list(dict), do: dict
-
-  defp any_key?(k, [k|_]), do: true
-  defp any_key?(k, [_|t]), do: any_key?(k, t)
-  defp any_key?(_k, []),   do: false
 end