@lexbuild/core

This package is part of the LexBuild monorepo, a tool that converts U.S. legislative XML into structured Markdown optimized for AI, RAG pipelines, and semantic search. See the monorepo for full documentation, architecture details, and contribution guidelines.

It provides the foundational building blocks for XML parsing infrastructure, AST definitions, and Markdown rendering for use by @lexbuild/usc and @lexbuild/cli.

Install

npm install @lexbuild/core

What's Included

XML Parser

Streaming SAX parser with namespace normalization for USLM documents.

import { XMLParser } from "@lexbuild/core";

const parser = new XMLParser();
parser.on("openElement", (name, attrs) => { /* ... */ });
parser.on("closeElement", (name) => { /* ... */ });
parser.on("text", (text) => { /* ... */ });

await parser.parseStream(readableStream);

AST Builder

Stack-based XML-to-AST construction with a section-emit pattern for bounded memory usage.

import { ASTBuilder } from "@lexbuild/core";

const builder = new ASTBuilder({
  emitAt: "section",
  onEmit: (node, context) => {
    // Called with each completed section subtree
  },
});

Markdown Renderer

Stateless AST-to-Markdown conversion with YAML frontmatter, cross-reference link resolution, and notes filtering.

import { renderDocument, generateFrontmatter, createLinkResolver } from "@lexbuild/core";

const markdown = renderDocument(sectionNode, frontmatterData, {
  linkStyle: "relative",
  resolveLink: resolver.resolve,
});

AST Node Types

Full type definitions for the legislative document AST: LevelNode, ContentNode, InlineNode, NoteNode, TableNode, and more.

import type { ASTNode, LevelNode, FrontmatterData, RenderOptions } from "@lexbuild/core";

Namespace Constants

USLM, XHTML, Dublin Core namespace URIs and element classification sets.

import { USLM_NS, XHTML_NS, LEVEL_ELEMENTS, CONTENT_ELEMENTS } from "@lexbuild/core";

API Reference

Documentation

• LexBuild Monorepo
• Architecture
• Output Format
• XML Element Reference
• Extending

License

MIT