drewc / smug-gerbil

Super Monadic Über Go-into : parser combinators for Gerbil Scheme

Super Monadic Über Go-into : Parsers and Gerbil Scheme

I discovered monads after writing a parser for org-mode and thinking there must be a better way.

It will have wonderful documentation at some point, once the Org Parser is complete so I know it quite well. For now, how a look at syntax.org in that project.

(def (HEADLINE (min-depth 1))
      (.let* ((s (STARS min-depth)) (k TODO-KEYWORD) (p PRIORITY)
              (c COMMENT)
              (title TITLE) (tags (.or (.begin0 TAGS (skip WS) EOL)
                                       (.begin EOL #f))))
        ['headline (list stars: s todo-keyword: k priority: p
                         title: (list->string title) tags: tags
                         commented?2: c footnote-section?: (footnote-section? title)
                         archived?: (archived? tags))]))

Emacs Indentation and Highlighting

(defun smug-gerbil-syntax ()
  (interactive)

  (gerbil-put-indent '(.begin .or .any) 0) 
  (gerbil-put-indent '(.let* .begin0)  1)

  (gerbil-fontlock-add
   (cons
    (concat
     "(" (regexp-opt '(".let*" ".begin" ".begin0" ".or" ".any" ".not")
                     t)
     "\\>")
    '(1 'font-lock-keyword-face  ))))

(add-hook 'gerbil-mode-hook 'smug-gerbil-syntax)