flourish

flourish is a Quarto extension for styling code in rendered code chunks.

Slides from useR!2025

Installation

Install by running in your terminal:

quarto add kbodwin/flourish

and add this yaml in your qmd:

filters:
 - flourish

Current abilities of the package

• Apply default yellow highlighting by specifying a target

#| flourish:
#| - target: "mean"

• Specify targets via regular expressions

#| flourish:
#| - target-rx: "[0-9]*"

• Provide custom styling

#| flourish:
#| - target:
#|      - "mean"
#|      - style:
#|            - "background-color: #FFC0CB;"

• Use mask: true to remove the original text of the target

#| flourish:
#| - target:
#|     - "mean"
#|     - mask: true
#|     - style: "text-decoration: underline;"

See example.qmd and its rendered counterpart for further details.

Future aspirations

• Allow for additional style attributes, e.g.

#| flourish:
#| - target:
#|     - "mean"
#|     - style: 
#|         - "color: transparent;"
#|         - hover:
#|             - "color: black;"

• Provide many shortcut styles, e.g. "mask-underline" as a shortcut.

• Allow for only targeting the first match (or first two matches, or second match, etc. etc.)

• Allow for more specificity by line, such as highlighting a full line, or only targeting matches in a particular range.

• Allow global YAML to flourish the whole document at once.

• Allow user to specify the class wrapper for targets, so they can also write their own custom class CSS directly.

• Add option to apply flourish to the code output as well. (This is fairly low-hanging fruit for text output but unlikely to work with complex output.)

• Maybe: Use similar syntax to flourish plaintext in a Quarto doc, e.g.

::: flourish
- target: mean

Let's flourish this text, that's what I mean.
:::

Bugs to fix

• Right now, I believe it's not sanitized against rx special characters; e.g. if you want to flourish the literal character "*" that will not work.

• In HTML, some special characters appear different, e.g. < appears as <. That means that choosing x <- 1:10 as a flourish target won't work, because the < won't get matched.

Things you might want but we don't plan to do

• Functionality for pdf or docx. This extension is written in JavaScript for HTML; any other doc formats would require a total rebuild from the ground up.

• Flourishing non-text output. For example, it would be tough to use code chunk YAML to automatically flourish words in a ggplot title.