Intent to Prototype: Parse processing instructions in HTML

[Chromestatus]

Contact emails

nrose...@chromium.org, foo...@chromium.org

Explainer

https://github.com/WICG/declarative-partial-updates/blob/main/patching-explainer.md#proposed-markup

Specification

https://github.com/whatwg/html/pull/12118

Summary

Processing instructions (syntax: <?target data>) are an existing DOM construct, exposed in XML, that allows node objects that are not elements but can have some semantic meaning for the processing of a document. For example, they can be used to denote ranges for streaming or highlighting without requiring new DOM elements and changing the DOM structure as far as CSS is concerned, or as directives for the HTML parser about how to buffer and stream.

Blink component

Blink>HTML>Parser

Web Feature ID

html

Motivation

The work on out of order streaming showed that defining declarative ranges with elements is insufficient, and there's need to be a "lighter" declarative way to denote ranges, that doesn't e.g. affect CSS relationships. This seems to unlock some future use-cases, such as declaratively denoting CSS custom highlights, and controlling the streaming/buffering of an HTML response.

Initial public proposal

https://github.com/WICG/webcomponents/issues/1116

Requires code in //chrome?

False

Tracking bug

https://issues.chromium.org/issues/481087638

Estimated milestones

No milestones specified

Link to entry on the Chrome Platform Status

https://chromestatus.com/feature/6534495085920256?gate=5601646610612224

This intent message was generated by Chrome Platform Status.