Go : assignment to entry in nil map
<p>When trying to set value to the <code>map</code>(<code>countedData</code>) in the below code, I am getting an error that says, <code>assignment to entry in nil map</code>. </p>

<pre><code>func receiveWork(out &lt;-chan Work) map[string][]ChartElement {

    var countedData map[string][]ChartElement

    for el := range out {
        countedData[el.Name] = el.Data
    }
    fmt.Println("This is never executed !!!")

    return countedData
}
</code></pre>

<p><code>Println</code> does not execute (as the error occurs on a lien before that). </p>

<p>There are some goroutines , that are sending data to channel, and <code>receiveWork</code> method should be making a map like this: </p>

<pre><code>map =&gt;
    "typeOne" =&gt; 
       [
         ChartElement,
         ChartElement,
         ChartElement,
       ],
    "typeTwo" =&gt; 
       [
         ChartElement,
         ChartElement,
         ChartElement,
       ]
</code></pre>

<p>Please help me fix the error.</p>