title: How to filter b-table rows using a custom filter-function?
body: <p>I'm trying to filter out some rows in a bootstrap-vue table using a custom filter function.</p>
  
  <p>I wrote a function that takes two arguments - a row object and an empty filter argument, and returns true or false, as in the <a href="https://bootstrap-vue.js.org/docs/components/table#custom-filter-function" rel="noreferrer">documentation</a>.</p>
  
  <p>I have tried to use the code provided in <a href="https://stackoverflow.com/questions/52415889/btable-filter-with-a-function#comment96462273_52416037">this</a> and <a href="https://stackoverflow.com/a/55489965/3969204">this</a> answers, but they doesn't work either. </p>
  
  <p>I've also tried to put <code>console.log(row, filter)</code> into the filterTable method but it doesn't write anything to the console.</p>
  
  <pre class="lang-html prettyprint-override"><code>&lt;template&gt;
    &lt;div&gt;
      &lt;b-table 
        striped hover 
        :items="items" 
        :filter=null 
        :filter-function="filterTable"&gt;&lt;/b-table&gt;
    &lt;/div&gt;
  &lt;/template&gt;
  </code></pre>
  
  <pre class="lang-js prettyprint-override"><code>export default {
      data() {
        return {
          items: [
            { age: 40, first_name: 'Dickerson', last_name: 'Macdonald' },
            { age: 21, first_name: 'Larsen', last_name: 'Shaw' },
            { age: 89, first_name: 'Geneva', last_name: 'Wilson' },
            { age: 38, first_name: 'Jami', last_name: 'Carney' }
          ]
        }
      },
  
      methods: {
        filterTable(row) {
          if (row.age &gt;= 40) {
            return false;
          } else {
            return true;
          }
        }
      }
  }
  </code></pre>
  
  <p>It's supposed to display people who are younger than 40 years old, but it displays all the records instead.</p>