   However, if the client had sent an expired or otherwise invalid token
   `verify/4` would have returned an error instead:
 
-      iex> Phoenix.Token.verify(secret, user_salt, expired, max_age: 86400)
+      iex> Phoenix.Token.verify(secret, namespace, expired, max_age: 86400)
       {:error, :expired}
 
-      iex> Phoenix.Token.verify(secret, user_salt, invalid, max_age: 86400)
+      iex> Phoenix.Token.verify(secret, namespace, invalid, max_age: 86400)
       {:error, :invalid}
 
   ## Options


      iex> user_id    = 99
      iex> secret     = "kjoy3o1zeidquwy1398juxzldjlksahdk3"
      iex> user_salt  = "user salt"
      iex> token      = Phoenix.Token.sign(secret, user_salt, user_id)

  The mechanism for passing the token to the client is typically through a
  cookie, a JSON response body, or HTTP header. For now, assume the client has


  The second argument is a [cryptographic salt](https://en.wikipedia.org/wiki/Salt_(cryptography))
  which must be the same in both calls to `sign/4` and `verify/4`.
  For instance, it may be called "user auth" and treated as namespace
  when generating a token that will be used to authenticate users on
  channels or on your APIs.

  The third argument can be any term (string, int, list, etc.)
  that you wish to codify into the token. Upon valid verification,
