Racket Syntax Highlighting for Pandoc-Flavored Markdown

Usage

Suppose you have a Pandoc-flavored markdown file with Racket code blocks of the form

```racket
(define (f x) (abs (- x 10)))
```

Add --syntax-definition=PATH TO racket.xml to your usual invocation of Pandoc in the command line and the generated HTML or LaTeX will have syntax-colored Racket code.

Example

Consider the Pandoc-flavored markdown file example.md included in the this repository's example folder.

I would normally run the following to generate a standalone HTML from example.md though it wouldn't color Racket blocks.

    $ pandoc \
    > --standalone \
    > --metadata title="Example" \
    > --output=example-no_rkt_hl.html \
    > example.md

Now that I have a Racket syntax definition namely racket.xml available I can instruct Pandoc to use it to highlight Racket code.

    $ pandoc \
    > --syntax-definition=../racket.xml \
    > --standalone \
    > --metadata title="Example" \
    > --output=example-rkt_hl.html \
    > example.md

I can add yet another command line argument to apply the alternative kate highlighting style that comes installed with Pandoc.

    $ pandoc \
    > --syntax-definition=../racket.xml \
    > --highlight-style=kate \
    > --standalone \
    > --metadata title="Example" \
    > --output=example-rkt_hl_kate.html \
    > example.md

I have included the files example-no_rkt_hl.html, example-rkt_hl.html and example-rkt_hl_kate.html as generated on my computer running pandoc 2.13 on macOS 11.1 in the examples folder.

Nuances

The highlighter assumes your Racket or Typed Racket code is free of syntax errors, in other words the code ought to be accepted by the Racket interpreter.

The highligher does not support S-expression comments, the nesting of block comments, #! comments or #!\ comments. Single line comments i.e. ; and block comments with one level of nesting e.g. #| a #| comment |# are okay.

Contributing

Please feel free to use the Issues tab to post questions and comments about the implementation of racket.xml and to suggest improvements.

Pull requests are welcome!

References

The Pandoc User's Guide for information on how to supply Pandoc with a new syntax definition file.

Emacs' racket-mode for the list of keywords as well as the strategy for highlighting #lang, module, define and define-values forms.

Working with Syntax Highlighting from The KatePart Handbook for instructions on writing a syntax definition from scratch.