CSS Module Scripts

[dandclark]

Request for Mozilla Position on an Emerging Web Specification

• Specification Title: CSS Module Scripts
• Specification or proposal URL: Explainer, HTML PR
• Mozillians who can provide input (optional): @annevk

Other information

This proposal has already been in discussion for a while now (long thread here, see also the TAG review), but I realized we don't have a mozilla/standards-positions entry on it yet so I think it would be useful to get an official position.

Landing the CSS Module Script HTML Spec PR is currently blocked on resolution of an open issue in the import assertions TC39 proposal. However import assertions is at Stage 3 so that proposal is unlikely to undergo significant changes.

[annevk]

I'm not sure I understand your last paragraph. It seems to me those integration concerns need to be sorted, no? Including what kind of host hook to provide.

Do you recall if we ever discussed the identifier name? Do we want to specifically assert it's CSS or is stylesheet or some such sufficient?

[dandclark]

@annevk Sorry, that paragraph was too vague. I agree that the integration concerns and the shape of the host hooks need to be settled before landing the HTML spec change. The import assertion proposal champions are joining an SES call this Wednesday to hopefully make some progress in that area.

I meant that most of the basic behavior of the proposal as observed by developers is unlikely to change much. For example, the fact that the import gives you a CSSStyleSheet, and the use of the import assertions syntax to convey the expected module type is unlikely to change, in my estimation, even if details about spec integration and behavior of undefined types need to be sorted out.

Regarding the identifier name, my understanding is that there was general agreement on using "css" as the type name, as in:

import styleSheet from "./styles.css" assert { type: "css" };

This was what I used in my slides (specifically, slide 7) in last year's TPAC discussion on the topic (notes here), and I don't recall disagreement on that point at the time. Happy to discuss alternatives though.

I like "css" because it's short and the use of the acronym would align nicely with "json" for JSON modules and maybe "html" someday:

import styleSheet from "./styles.css" assert { type: "css" };
import myJson from "./data.json" assert { type: "json" };
import doc from "./content.html" assert { type: "html" };

[annevk]

Thanks, provided the details are settled, I would recommend we mark this as worth prototyping.

[annevk]

Closing this as per the previous comment.