capybara/ext-mathml/main.rkt

#lang racket/base

(require racket/list racket/match racket/runtime-path racket/string xml
         "../util.rkt")

(define-runtime-path *js-path* "mathml-render.js")

(provide transform-xexprs scss-files)

(define (mathtex-type? s)
  (and (string? s) (regexp-match #rx"^math/tex" s) #t))

(define (transform-xexprs xexprs)
  (map transform-xexpr xexprs))

(define (run-mathjax source block?)
  (define out-str (run-external (list "node" (path->string *js-path*)) source))

  (match-define (list 'math attrs bodies ...) (string->xexpr out-str))
  `(math ,(cons (list 'display (if block? "block" "inline"))
                (filter (λ (x) (not (eq? (first x) 'display))) attrs))
         ,@bodies))

(define (transform-xexpr xexpr)
  (match xexpr
    [(list 'script (list (list 'type (? mathtex-type? type)))
           bodies ...)
     (define body (apply string-append bodies))
     (define block? (> (length (string-split type " ")) 1))
     (run-mathjax body block?)]
    [(list tag attrs body ...)
     (cons tag (cons attrs (map transform-xexpr body)))]
    [(? string? str) str]))

(define scss-files '())