pandoc/pandoc.r5rs.scm

113 lines
4.7 KiB
Scheme

(define (join-adjacent type? type-append list)
(let loop ((new-list '()) (list list))
(if (null? list) (reverse new-list)
(loop (if (and (not (null? new-list))
(type? (car new-list))
(type? (car list)))
(cons (type-append (car new-list)
(car list))
(cdr new-list))
(cons (car list) new-list))
(cdr list)))))
(define (join-adjacent-strings list)
(join-adjacent string? string-append list))
(define (vector-refs vec . indexes)
(let loop ((obj vec) (indexes indexes))
(if (null? indexes) obj
(loop (vector-ref obj (car indexes))
(cdr indexes)))))
(define (pandoc-json->sxml json)
(define (convert-block-or-inline element)
(if (string? element) element (convert-block element)))
(define (convert-block block)
(let ((type (cdr (assq 't block))))
(define (contents) (cdr (assq 'c block)))
(define (contents-list) (vector->list (contents)))
(cond ((equal? type "Space")
" ")
((equal? type "Str")
(contents))
((equal? type "BulletList")
`(ul
,@(map (lambda (list-element)
`(li ,@(convert-many (vector->list list-element))))
(contents-list))))
((equal? type "BlockQuote")
`(blockquote
,@(convert-many (contents-list))))
((equal? type "Code")
`(code ,@(convert-many (cdr (contents-list)))))
((equal? type "CodeBlock")
`(pre (@ (data-syntax ,@(join-adjacent-strings
(vector->list
(vector-refs (contents) 0 1)))))
,@(convert-many (cdr (contents-list)))))
((equal? type "Emph")
`(em ,@(convert-many (contents-list))))
((equal? type "Header")
(let* ((level (car (contents-list)))
(h-tag (string->symbol
(string-append "h" (number->string level)))))
`(,h-tag ,@(convert-many (vector->list
(list-ref (contents-list) 2))))))
((equal? type "Link")
`(a (@ (href ,(join-adjacent-strings
(vector->list (vector-ref (contents) 2)))))
,@(convert-many (vector->list (vector-ref (contents) 1)))))
((equal? type "Plain")
`(span ,@(convert-many (contents-list))))
((equal? type "Para")
`(p ,@(convert-many (contents-list))))
((equal? type "SoftBreak")
"\n")
((equal? type "Strong")
`(strong ,@(convert-many (contents-list))))
((equal? type "Table")
(let ((headings (vector-refs (contents) 3 1 0 1)))
`(table
(tr
,@(map (lambda (cell)
(let ((elements (vector->list
(vector-refs cell 4))))
`(th ,@(map convert-block-or-inline elements))))
(vector->list headings)))
,@(map (lambda (row)
`(tr ,@(map (lambda (cell)
(let ((elements
(vector->list
(vector-refs cell 4))))
`(td ,@(map convert-block-or-inline
elements))))
(vector->list (vector-refs row 1)))))
(vector->list (vector-refs (contents) 4 0 3))))))
(else
(error "Unknown type in pandoc JSON" type)))))
(define (convert-many elements)
(join-adjacent-strings (map convert-block-or-inline elements)))
(define (assert-supported-version)
(let* ((version (cdr (assq 'pandoc-api-version json)))
(major (vector-ref version 0)))
(unless (= major 1)
(error "Pandoc API version is not 1.x" version))))
(assert-supported-version)
(convert-many (vector->list (cdr (assq 'blocks json)))))
(define (pandoc-port->sxml input-format input-port)
(pandoc-json->sxml (pandoc-port->json input-format input-port)))
(define (pandoc-file->json input-format input-filename)
(call-with-binary-input-file
input-filename
(lambda (input-port) (pandoc-port->json input-format input-port))))
(define (pandoc-file->sxml input-format input-filename)
(pandoc-json->sxml (pandoc-file->json input-format input-filename)))