JavaScript compiler error - Google Tag Manager

Question

I currently have a script in Google Tag Manager, which when I am going ot publish, is giving me x 2 JavaScript compiler errors

JavaScript compiler error   

Error at line 3, character 7: This language feature is only supported for ECMASCRIPT6 mode or better: const declaration.

Error at line 4, character 18: This language feature is only supported for ECMASCRIPT6 mode or better: arrow function.

Here is my code:

<script>
    (function() {
      const h4 = document.querySelectorAll('.h4');
      h4.forEach(el => {
        el.innerHTML = el.innerHTML.replace(/sweater/gi, 'jumper');
      });
    })();
</script>

This is working correctly in DevTools. Is there a one size fits all resolution for these errors, or is it bespoke depending on your code?

Thanks,

According to Google 'Sandboxed JavaScript is based on ECMAScript 5.1. Some ECMAScript 6 features such as arrow functions and const/let declarations are available.' - developers.google.com/tag-manager/templates/…. But it looks like they aren't allowed when you publish. The only robust solution is not to use them I guess, or can you just target EcmaScript 6 when you publish? — Toby
– Toby, Commented Aug 18, 2020 at 7:47
@Toby, that goes only for custom templates. Custom HTML tags do not support ES6 at all. — Eike Pierstorff
– Eike Pierstorff, Commented Aug 18, 2020 at 8:35

Mark Baijens · Accepted Answer · 2020-08-18 07:45:08Z

1

I don't know google tag manager. Perhaps you can set that up to support ECMASCRIPT6.

If you want it to work on an older version of ECMASCRIPT then you can replace const with var and use an anonymous function instead of an arrow function.

(function() {
  var h4 = document.querySelectorAll('.h4');
  h4.forEach(function(el) {
    el.innerHTML = el.innerHTML.replace(/sweater/gi, 'jumper');
  });
})();

<h4 class="h4">Black sweater</h4>

answered Aug 18, 2020 at 7:45

Mark Baijens

13.3k11 gold badges51 silver badges77 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

JackNesbitt Over a year ago

This worked perfectly! Thanks for the resolution and feedback Mark

Collectives™ on Stack Overflow

JavaScript compiler error - Google Tag Manager

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related