Towards a simpler and extensible CSL 2.0; or What can we learn from citeproc (hs) and djot?


I merged sorting and grouping logic this weekend, and I’ve integrated it into a processing AST.

The Internal model and AST

The grouping logic is added to the procHints property on an intermediate ProcReference class, which includes formatting methods. That property I currently only use for disambiguation …

  ProcReference {
    data: {
      type: "book",
      title: "The Title",
      author: [ { name: "Doe, Jane" } ],
      issued: "2023",
      citekey: "doe2"
    procHints: { groupIndex: 2, groupKey: "Doe, Jane:2023", groupLength: 2 }

… and then incorporate in the rendering AST, which is just the input templates with added procValue property:

    [ { contributors: "author", procValue: "Doe, Jane" } ],
      date: "issued",
      format: "year",
      wrap: "parentheses",
      procValue: "2023b"
    [ { title: "title", procValue: "The Title" } ],

FWIW, this processing model is conceptually similar to the design I used for the very first CSL implementation, in XSLT 1.0, but of course using native and close-to-native data structures (as in, input format very closely maps to and from internal data structures).

Code generation example

A little demo repo to demonstrate the code generation:

If you run the script, it will create the rust module files, and build that with the tiny source file, which demonstrates the generated code correctly deserializes and serializes the Style model, in this case translated to a Rust struct.

❯ time target/debug/csln-rs style.csl.yaml bibliography.yaml
The name of the style is: "APA"
The number of entries in the bibliography is: 5

Executed in    2.74 millis    fish           external
   usr time    1.16 millis  406.00 micros    0.75 millis
   sys time    1.62 millis  115.00 micros    1.51 millis

The Plan, milestones

Here’s how I imagine the milestones to build this out to a formal release. I’m already ahead of schedule on my own, so I’m optimistic about accomplishing the plan with help.

Aside: I’ve partly set the milestones up because there’s a possibility some comp sci students may work on pieces of this later this year and next.