Provide read-only access to the parsed mapping object

[bahrus]

It would only take a single line of code for application logic to parse the JSON string of the importmap:

const p = JSON.parse(document.head.querySelector('script[type="importmap"]').innerHTML)

But assuming the browser will parse it, could it not expose the parsed object in some way?

I know the intention is to not allow for adding metadata, but scheming developers like me will still probably be quite tempted to add metadata (for example, appending #myMetaInfo= after the path to a js file).

Any harm done in exposing the parsed object? That could reduce cpu a bit.

[ljharb]

Unless it was a getter that returned a new object every time, then I’d wonder what happens if you mutate that object - and if the object is mutable for future accesses, then the only robust thing is to manually parse anyways, so the object access seems to lose its value :-/

[domenic]

Yeah, I think we not rush into a solution here, to leave open the door for a future, mutable-in-a-controlled-way, "import map object model" API that allows runtime changes to import mapping.

For example, such an API would probably be a per-realm representation of the merged import maps, and not per-script element. So we wouldn't want to provide the functionality equivalent to the OP since that wouldn't mesh well with the future work.