Note: This is a fork of jotdown pursuing slightly different API design and async support. All credit for the original implementation goes to the original authors.

Jotup

API documentation | Repository

Jotup is a pull parser Rust library for the Djot markup language. It parses a Djot document into a sequence of events and may also render the events to HTML.

Jotup aims to be fast and efficient, using a minimal number of allocations. The API should use idiomatic Rust and be easy to use and flexible. The event interface allows downstream crates to e.g. construct an AST or generate any type of output format. It also allows one to perform filters on the document before generating the output. Jotup aims to be feature complete and match the syntax reference and the reference implementation in terms of output.

Another goal is to keep the implementation minimal and build times low. The current implementation has zero dependencies, if major non-essential features are added or larger dependencies are utilized, these should be optional using feature flags.

Jotup supports Rust edition 2021, i.e. Rust 1.82 and above.

Usage

Jotup is primarily a parsing library but also has a minimal CLI implementation and a simple web demo version.

Library

The Jotup API is inspired by pulldown-cmark and is overall very similar. The Jotup crate contains in-source documentation, a rendered version is available at https://docs.rs/jotup.

While Jotup is usable, it is still in development and breaking changes to the API may occur. The Djot syntax is also not stabilized and may change.

CLI

The Jotup crate contains a minimal implementation of a CLI that simply reads from standard input and writes HTML to standard output. It can be built from this repository and run locally with cargo:

$ cargo build --release
$ echo "hello world" | ./target/release/jotup
<p>hello world</p>

Note: Jotup is not currently published to crates.io. You can install it from source:

$ cargo install --path .

It will be placed in ~/.cargo/bin/jotup.

Web demo

The web demo is a version of Jotup compiled to WebAssembly and runnable in a web browser. It is useful for experimenting with the djot syntax and exploring what events are emitted or what output is rendered.

You can run it locally:

$ cd examples/jotup_wasm
$ make run

You may need to install wasm-pack and make sure your Rust compiler has the WebAssembly backend.

Status

Correctness

As of writing, Jotup implements all current features of the Djot syntax. Any difference in parsing or HTML rendering from the reference implementation is considered a bug.

Feature requests for changed syntax or HTML rendering will be implemented if it is agreed to be implemented in the reference implementation first. Create a new issue or a new discussion in the official djot repo first for such requests.

There are still some known HTML differences from the reference implementation. There are two test suites that compares Jotup's HTML output with that of the reference implementation. Their known failures are listed in tests/html-ut/skip and tests/html-ref/skip.

One of the suites uses the unit tests of the reference implementation and runs them with Jotdown. It can be run with:

$ make test_html_ut

Another target uses the reference implementation to generate html output for its benchmark files and compares it to the output of Jotup:

$ make test_html_ref

Note that it requires node in order to run the reference implementation.

Performance

There are benchmarks available to measure the performance. The input files are borrowed from the reference implementation. To fetch the input files symlink them to the bench directory, run:

make bench

To run the benchmarks, use

cargo bench -p bench-crit [filter]

Alternatively, if cargo-criterion is installed:

cargo criterion -p bench-crit -- [filter]

There are also external benchmarks that compare the original jotdown to other markdown/djot implementations:

jotup 0.10.0