parseToAst Playground

Inspect the raw mdast tree produced by zfb-md-wasm before zfb visitors run.

Run to inspect the raw mdast tree.

Choose Admonition directive to enable the raw parser's directives option. The result contains a generic containerDirective named note; parseToAst deliberately does not consult the component registry or run the visitor that would turn it into <Note>.

The raw parser tier

parseToAst is the earliest useful inspection tier in the @takazudo/zfb-md-wasm API. It parses Markdown or MDX into the raw mdast-shaped data produced by markdown-rs, before zfb visitors transform that tree into HTML or compiled JSX. This makes it useful when you want to see what the parser actually recognized, including positions and MDX-shaped nodes, without introducing a renderer's interpretation.

The sample includes ordinary Markdown, a top-level import, and a JSX element with an attribute. Top-level MDX import and export lines deliberately degrade to paragraphs here: the WebAssembly boundary has no JavaScript/acorn parser, so the tree has no mdxjsEsm nodes or estree data. Also, mdxJsxAttribute and its value/expression-attribute siblings have no position, because markdown-rs does not model attribute positions. Both differences are documented contract divergences from remark.

When to use toMdastRoot

Enable toMdastRoot when you want a strict, ecosystem-compatible mdast root for existing mdast or unist visitors. It validates the raw tree and returns a detached tree that narrows cleanly by node type. It is intentionally stricter than the raw tier and throws MdastAdapterError for unsupported or malformed nodes, so the playground checks parse diagnostics and a non-null AST first and renders adapter failures as diagnostics.

For a browser-side pipeline walkthrough, see Browser Markdown Preview.