title: Immer does not support setting non-numeric properties on arrays
body: <p>I'm trying to update a piece of state with an array of data that I'm getting from the server. This is my reducer:</p>
  
  <pre><code>const schoolsDataReducer = (state = { data: [] }, action) =&gt;
    produce(state, draft =&gt; {
      switch (action.type) {
        case SET_INITIAL__DATA:
          draft.data = [...action.payload.data]
          break
      }
    })
  </code></pre>
  
  <p>I get this error: </p>
  
  <blockquote>
    <p>"Immer does not support setting non-numeric properties on arrays: data"</p>
  </blockquote>
  
  <p>How am I supposed to store an array of objects?<br>
  Are arrays in the state considered bad practice?<br>
  Am I missing something?</p>