litedown: R Markdown Reimagined

2011-2023

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A brief history

• 1984: Donald Knuth, Literate Programming

• 1987: WEB and CWEB

• 1989: noweb

• 2002: Sweave, the pioneer in automated report generation

  • R + LaTeX

  • RIP, Fritz Leisch (1968-2024)!

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• 2011: knitr (language-agnostic)

  • 2011-10-16: initial development

  • 2012-01-17: initial CRAN release

  • 62 CRAN releases in 12 years

• 2012: the first generation of R Markdown, based on the R package markdown (N.B. not rmarkdown!), and only supports HTML output

• 2014: the second generation of R Markdown, i.e., the rmarkdown package, based on Pandoc for multiple output formats (HTML, Word, PDF, PowerPoint, E-book, etc.)

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R Markdown extensions, since 2016

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Quarto (2022)

• R Markdown = Markdown + computing languages

• In theory, you can use dozens of computing languages in R Markdown (not limited to R), but R has to be installed in the first place, no matter if you use R or not in R Markdown

• Generalizing 10+ years of experience from R Markdown (e.g., bookdown) to a wider community (e.g., Python and Julia)

• On the Markdown side

  • Quarto implements all features using Pandoc Lua filters, which means Markdown features often work across multiple output formats, e.g., cross-references, subfigures, etc.

• On the computing side

  • Quarto supports both knitr and jupyter, so Python users can use the jupyter engine (no need to install R), and R users can continue to use knitr

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litedown (2024)

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Recall:

Why do we use Markdown?

Simplicity

What was Markdown invented for?

HTML

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⚡ litedown ⚡

Make Markdown HTML Again

Do one thing, and do it well

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R Markdown in 2012 vs 2024

	2012	2024
Output formats	HTML	HTML, LaTeX, PDF, Word, PowerPoint, EPUB, …
Applications	Reports	Reports, slides, articles, books, websites, dashboards, …
Backend	sundown (a tiny C library)	Pandoc
R package dependencies	0	25
Package size	~2Mb	~83Mb (Pandoc: 152Mb)

The above comparison does not include R Markdown extension packages such as bookdown and blogdown, which are even heavier.

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Minimalism: my new journey

• litedown: https://github.com/yihui/litedown

• The goal: litedown = min{knitr + evaluate + rmarkdown + bookdown + blogdown + pagedown + xaringan + tufte} - Pandoc - Hugo - GitBook - Bootstrap - jQuery

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• Re-implementing 12 years of work with fewer features and dependencies

  • Easier to develop, install, and manage (built on top of xfun and commonmark, and no dependency on Pandoc or knitr)

  • Also easier to be embedded in other applications (e.g., WebAssembly)

• Be determined to say No (if you want rich features, you should use rmarkdown or Quarto instead)

• Choose a stable foundation to develop software on top of

  • e.g., base R, commonmark

• Hoping to declare “feature-complete” in a few months

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In HTML I believe

• As a software developer, I feel it’s tempting to pursue rich features

• HTML only requires a web browser, which everyone has; other document formats require special tools

• CSS and JavaScript can make HTML extremely powerful

  • you can manipulate the page arbitrarily with JS (no need to learn Lua)

  • you can print HTML to PDF (no need to battle with LaTeX)

• If only one document format would survive in the far future, I believe it will be HTML

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Demo

• Installation:

  remotes::install_github('yihui/litedown')
  

• Rmd example: https://gist.github.com/yihui/44ccbae0b3d3ec3669d357f218b2f32d

• Preview and build R Markdown: litedown::roam()

• Figures and tables / Time code chunks / Execution order / R scripts, books, and slides / JS and CSS assets

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Thank you!

https://yihui.org