Implements support for `// deno-doc-ignore` and `// deno-doc-ignore-file` comment directives that allow hiding specific lines or entire files from documentation. The logic parses comment lines before or after a code construct and applies ignore rules based on optional codes (e.g., 'no-jsdoc'). This is a self-contained, well-structured pattern that could be reused in any documentation generator or linting tool to handle per-line or per-file suppression directives.

Processes code blocks in JSDoc `@example` tags to support hidden lines (lines starting with `# `, similar to rustdoc). It strips the `#` prefix and removes those lines before rendering, allowing examples to show only explanatory code while keeping boilerplate hidden. This is an isolated utility function with clear input/output contracts, easily extractable for any documentation tool that renders code examples.

Provides a generic partitioning algorithm that takes a list of documentation nodes (symbols) and groups them by kind (functions, classes, etc.), while flattening namespaces and sorting symbols. It also collects module-level documentation and handles references. The logic is decoupled from the rendering layer and uses a configurable `SymbolTransformer` trait. This pattern is reusable for any tool that needs to categorize and order a flat list of API symbols into a hierarchical display.

Implements the core diff engine that compares two parsed documentation outputs (`ParseOutput`). It computes per-module and per-symbol changes (added, removed, modified) with detailed declaration-level diffs. It includes rename detection using `RenameCandidate` traits with similarity heuristics (small vs large changes) and tracks changes in parameters, type parameters, JSDoc, and decorators. While coupled to the crate's data types, the pattern of structured API diffing with rename detection is a well-crafted, non-trivial component that could inspire similar engines for other languages or schemas.