title: ReactJS Filter Box: Expected an assignment or function call and instead saw an expression no-unused-expressions
body: <p>I am trying to create a filter Box where the user can filter videos depending on the Language (Hindi, English, Tamil, Malayalam, Arabic and Tagalog). I keep getting this error:  Line 42:29:  Expected an assignment or function call and instead saw an expression  no-unused-expressions. I am trying to understand the error and why does it show. I am getting the error start from the last useEffect that I created until the return statement. Can someone explain the error to me?</p>
  <p>Here is my code:</p>
  <pre><code>import { useEffect, useState } from &quot;react&quot;;
  import &quot;./App.css&quot;;
  import RadioList from &quot;./components/RadioList&quot;;
  
  function App() {
    const [data, setData] = useState([]);
    const [filterData, setFilterData] = useState([]);
    const [language, setLangauge] =  useState(&quot;&quot;);
  
    useEffect(() =&gt; {
      const getData = () =&gt; {
        fetch(&quot;radio.json&quot;, {
          headers: {
            &quot;Content-Type&quot;: &quot;application/json&quot;,
            Accept: &quot;application/json&quot;,
          },
        })
          .then(function (response) {
            console.log(response);
            return response.json();
          })
          .then(function (myJson) {
            console.log(myJson);
            setData(myJson);
          });
      };
      getData();
  
    }, 
    
    []);
    useEffect(() =&gt; {
      setFilterData(data) 
  
  
  
    },
    [data]);
  
    useEffect(() =&gt; {
      setFilterData(
        data.filter(value =&gt; {value.language === language})
      )
    },
    [language]);
  
  
    return (
      &lt;div className=&quot;mt-5 flex flex-col items-center&quot;&gt;
         &lt;select
                value=&quot;Choose a Language&quot;
          &gt;
        {filterData.map((radioItem) =&gt; {
          &lt;option language={radioItem.language}&gt;
        &lt;/option&gt;
        })}
         &lt;/select&gt;
        {data.map((radioItem) =&gt; {
          return (
            &lt;RadioList
              server_url={radioItem.server_url}
              title={radioItem.name}
              language={radioItem.language}
            /&gt;
          );
        })}
        
       
      &lt;/div&gt;
    );
  }
  
  export default App;
  
  </code></pre>