-webide-representation doesn't work for parse instances that were not invoked before

[generalmimon]

Try this example in the Web IDE:

meta:
  id: webide_repre_inst_pos
seq:
  - id: a
    type: foo
types:
  foo:
    -webide-representation: '{inst_pos:dec}'
    instances:
      inst:
        value: inst_pos
      inst_pos:
        pos: 0
        type: s1

After expanding a, the result looks like this:

Clearly, the -webide-representation key does not work - it should be a [Foo]: 82 instead of just a [Foo]. For value instances, it does work - try switching to the value instance inst by changing -webide-representation: '{inst_pos:dec}' in the above snippet.

However, I noticed that the instPos is collapsed in the object tree, which means that it uses lazy evaluation and it has not yet been evaluated. So I tried to change -webide-parse-mode to eager - that tells the Web IDE not to wait for user interaction before invoking the instance but invoke it right away:

       inst_pos:
         pos: 0
         type: s1
+        -webide-parse-mode: eager

And indeed, the problem gets fixed as soon as the setting is added:

So we need to ensure that fields referenced in -webide-representation are invoked if needed.