No Json serializer found
<p>I am doing the sample Play project from <a href="https://www.playframework.com/" rel="nofollow">https://www.playframework.com/</a>. I have reproduced the code from the tutorial.</p>

<p>However, on this code from the controller <code>Application</code>:</p>

<pre><code>  def getPersons = Action {
    val persons = DB.query[Person].fetch
    Ok(Json.toJson(persons))
  }
</code></pre>

<p>I am getting this error:</p>

<pre><code>No Json serializer found for type Stream[models.Person with sorm.Persisted]. Try to implement an implicit Writes or Format for this type.
</code></pre>

<p>But I think this shouldn't be the case, because an implicit format for this type is already implemented in the model <code>Person</code>:</p>

<pre><code>case class Person(name: String) {

  implicit val personFormat = Json.format[Person]
}
</code></pre>

<p>And this model is imported in the controller <code>Application</code>.</p>

<p>Is the implicit <code>Format</code> not well defined?</p>