I'm trying to pass a variable to my javascript regular expression, but it returns null all the time. Regular expression is correct, but, Im unable to execute it on the JS. Below is my code:

'use strict';

  function matchExp(val) {
    let text = 'Is this " all": there is?';
    var match_pat = '[^"]* all\b[^"]*("\s*:)'
    var regMatch = new RegExp(match_pat, 'g');
    return(text.match(regMatch))
  }

  console.log(matchExp())
  module.exports = {
    matchExp
  }

**Expected Result**: "all":