Map in html templates

Hi, I’m trying to migrate a load of razor views to templates (loving it currently), but I can’t seem to get the map filter working in an html file - I have also tried using your examples from the docs as per below - should this work?

I am getting:

System.ArgumentException: Invalid syntax near ‘{{ range(3)
| map => it + 5
| m…’
at ServiceStack.Templates.PageResult.get_Result() at offset 54

  <p>User <strong>{{user.displayName}}</strong> made the following changes:</p>
        {{ ['zero','one','two','three','four','five','six','seven','eight','nine'] | assignTo:digits }}
        {{ range(3) 
        | map => it + 5
        | map => digits[it] | join(`\n`) }}


Are you using the latest v5.2? That expression works when posted in