High Order Function

    <script>
    const oneWord = function (str){
      return str.replace(/ /g,'').toLowerCase();
    };
    const upperFirstWord = function (str) {
      const [first, ...others] = str.split(' ');
      return [first.toUpperCase(), ...others].join(' ');
    };
    //Higher-Order function
    const transformer = function (str, fn){
      console.log(`Original string: ${str}`);
      console.log(`Transformed string: ${fn(str)}`);
      console.log(`Transformed by: ${fn.name}`);
    };

    transformer('JavaSCRIPT is the best!', upperFirstWord);
    </script>