Module webui 

WebUI Framework parser plugin.

Overview

Compiles HTML templates into structured metadata objects stored as JSON data plus component-local condition closure arrays in the protocol. During SSR the handler emits metadata in an application/json data block and only emits the closures as JavaScript. During SPA navigation the router registers the JSON data directly and evaluates only the closures. Each metadata object contains marker-free static HTML plus locator arrays for client-created DOM (tx, ag, c/r slots) and semantic arrays (a, c, r, eg, re, b). The client runtime resolves those locators once and then patches direct node references — no template string parsing, no regex, no DOM scanning on the client-created path.

Metadata object format

{
  "h": "<button class=\"item\"><span></span></button>",
  "tx": [[[[0, 0], 0], [["title"]]]],
  "a": [["title", 0, "title"]],
  "ag": [[[0], 0, 1]],
  "c": [[[0, ["state"]], 0, [[0], 1]]],
  "eg": [["click", [["onClick", [], [0]]]]],
  "b": [{ "h": "<span class=\"check\">✓</span>" }],
  "re": [["submit", "onSubmit", [["e"]]]]
}

Plugin data protocol

Each element with attribute bindings or events produces a 12-byte Plugin fragment via finish_element:

Bytes	Field	Description
0–3	binding_count	Number of dynamic attribute bindings
4–7	event_start_idx	Starting index in the global event list
8–11	event_count	Number of @event attrs on this element

The handler plugin decodes this to emit data-w-* binding markers and single data-ev="COUNT" event markers on SSR HTML only. Compiled templates keep the same binding/event indices but encode client targets via locator arrays instead of embedding client-only marker attrs/comments in h.

Lifecycle

1. classify_attribute — intercepts @event attributes, counts them per-element, and keeps them out of the parsed protocol.
2. finish_element — encodes the accumulated event count plus attribute binding count into 12 bytes.
3. register_component_template — caches the component’s plugin-facing template HTML for later compilation (deduplicates by tag name).
4. take_component_templates — called after parsing is complete; compiles each tracked component into JSON metadata plus condition closures.

Structs

WebUIParserPlugin

WebUI Framework parser plugin.

Functions

generate_compiled_template

Generate a compiled template as JSON-safe metadata.