title: Assignment to property of function parameter (no-param-reassign)
body: <p>I have this function and while I have this working nicely, I'm getting ESLint error saying</p>
  
  <pre><code>57:5  error  Assignment to property of function parameter 'result'  no-param-reassign   
  66:5  error  Assignment to property of function parameter 'result'  no-param-reassign
  </code></pre>
  
  <p>I'm unsure how to correctly resolve</p>
  
  <pre class="lang-js prettyprint-override"><code>export const fn = article =&gt; article.categoryValueDtoSet.reduce((result, item) =&gt; {
    if (item.language) {
      const language = item.language.languageValue;
      const category = item.categoryValue;
      result[language] = category;
    }
    return result;
  }, { it: undefined, de: undefined, en: undefined );
  </code></pre>
  
  <p>I did some research and it seems I need to use <code>Object.assign</code> and I tried it, but probably did it wrong.
  How should I write my function, that I can resolve my problem?</p>