Declarative Partial Updates

Summary: HTML primitives for updating part of a document without a full navigation. The same-document navigation work is split across several proposals. This directory is a playground for the pieces that can be exercised now.

Docs: Declarative partial updates | Chrome for Developers

Repo: WICG/declarative-partial-updates

Out-of-order streaming shipped in Chrome 150. The insertion/streaming methods and declarative fragments need chrome://flags/#enable-experimental-web-platform-features. Insertion methods are planned for Chrome 155. Declarative fragments are an Intent to Prototype.

Demos

• Out-of-order HTML streaming — <template for> with <?start>, <?end>, and <?marker>
• Renewed HTML insertion and streaming methods — setHTML / appendHTML / beforeHTML and the stream*HTML counterparts
• Declarative fragments — <template src>, buffer, and sanitize

Explainers without a demo here yet: route matching, preserve, snap to activate.

Used together

=== This is a demo of parser patches, streamed <template for> updates, and a declarative fragment include in one document. ===

• processing instructions parse as ProcessingInstruction
• a later <template for> patches an earlier marker
• streamAppendHTMLUnsafe patches an existing marker
• <template for src> includes a fragment

Parser patch has not run.