Unless I'm missing something, you cannot use forEach on a Javascript object as of now (or map, reduce, every, some and other methods that are available on Array.prototype).

The only way is to use:

  for(var key in obj) {...}

As for interpolation, I indeed missed the bit about quasis. Though I really wonder why they would still use concatenation if they can interpolate... Maybe to only show one feature at a time, which I guess makes sense.