title: flutter: A value of type 'Future<String>' can't be assigned to a variable of type 'String'
body: <p>I don't understand how to lead to one type
  my function:</p>
  <pre><code>Future&lt;String&gt; getToken(String login) async {
      final data = await (select(authInfos)
            ..where((tbl) =&gt; tbl.login.equals(login)))
          .getSingle();
      return data.token;
    }
  </code></pre>
  <p>row with error:</p>
  <pre><code>String token = myDatabase.authInfosDao.getToken(login);
  </code></pre>