ob-scopes.el

;;; ob-scopes.el --- org-babel functions for Scopes language evaluation

;; Copyright (C) your name here

;; Author: Samuel D. Lotz
;; Keywords: literate programming, reproducible research
;; Homepage:
;; Version: 0.1

;;; License:

;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 3, or (at your option)
;; any later version.
;;
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;; After that continue by creating a simple code block that looks like e.g.
;;
;; #+begin_src template

;; test

;; #+end_src

;; Finally you can use `edebug' to instrumentalize
;; `org-babel-expand-body:scopes' and continue to evaluate the code block. You
;; try to add header keywords and change the body of the code block and
;; reevaluate the code block to observe how things get handled.

;;; Requirements:

;;; The `scopes` runtime executable must be installed and on `PATH`

;;; Code:
(require 'ob)
(require 'ob-ref)
(require 'ob-comint)
(require 'ob-eval)

;; File extensions associated with the language
(add-to-list 'org-babel-tangle-lang-exts '("scopes" . "sc"))

;; TODO: optionally declare default header arguments for this language
(defvar org-babel-default-header-args:scopes '())

;; This function expands the body of a source code block by doing things like
;; prepending argument definitions to the body, it should be called by the
;; `org-babel-execute:scopes' function below. Variables get concatenated in
;; the `mapconcat' form, therefore to change the formatting you can edit the
;; `format' form.
(defun org-babel-expand-body:scopes (body params &optional processed-params)
  "Expand BODY according to PARAMS, return the expanded body."
  (require 'inf-scopes nil t)
  (let ((vars (org-babel--get-vars (or processed-params (org-babel-process-params params)))))
    (concat
     (mapconcat ;; define any variables
      (lambda (pair)
        (format "%s=%S"
                (car pair) (org-babel-scopes-var-to-scopes (cdr pair))))
      vars "\n")
     "\n" body "\n")))

;; This is the main function which is called to evaluate a code
;; block.
;;
;; This function will evaluate the body of the source code and
;; return the results as emacs-lisp depending on the value of the
;; :results header argument
;; - output means that the output to STDOUT will be captured and
;;   returned
;; - value means that the value of the last statement in the
;;   source code block will be returned
;;
;; The most common first step in this function is the expansion of the
;; PARAMS argument using `org-babel-process-params'.
;;
;; Please feel free to not implement options which aren't appropriate
;; for your language (e.g. not all languages support interactive
;; "session" evaluation).  Also you are free to define any new header
;; arguments which you feel may be useful -- all header arguments
;; specified by the user will be available in the PARAMS variable.
(defun org-babel-execute:scopes (body params)
  "Execute a block of Scopes code with org-babel.
This function is called by `org-babel-execute-src-block'"
  (message "executing Scopes source code block")
  (let* (
         (processed-params (org-babel-process-params params))
         ;; ;; set the session if the value of the session keyword is not the
         ;; ;; string `none'
         ;; (session (unless (string= session "none")
         ;;           (org-babel-scopes-initiate-session
         ;;            (cdr (assq :session processed-params)))))
         ;; ;; variables assigned for use in the block
         (vars (org-babel--get-vars processed-params))
         (result-params (assq :result-params processed-params))
         ;; ;; either OUTPUT or VALUE which should behave as described above
         (result-type (assq :result-type processed-params))
         ;; ;; expand the body with `org-babel-expand-body:scopes'
         (full-body (org-babel-expand-body:scopes
                     body params processed-params))
         ;; the temporary file path
         (in-file (org-babel-temp-file "prefix" ".sc"))
         )

    ;; actually execute the source-code block either in a session or
    ;; possibly by dropping it to a temporary file and evaluating the
    ;; file.

    ;; write the body to the temporary file
    (with-temp-file
      in-file
      (insert body)
      )

    ;; then evaluate the file with the scopes executable
    (org-babel-eval
       (format "scopes %s" ;in-file
               (org-babel-process-file-name in-file)
               )
       ""
       )

    ;; for session based evaluation the functions defined in
    ;; `org-babel-comint' will probably be helpful.
    ;;
    ;; for external evaluation the functions defined in
    ;; `org-babel-eval' will probably be helpful.
    ;;
    ;; when forming a shell command, or a fragment of code in some
    ;; other language, please preprocess any file names involved with
    ;; the function `org-babel-process-file-name'. (See the way that
    ;; function is used in the language files)
    ))

;; This function should be used to assign any variables in params in
;; the context of the session environment.
;; (defun org-babel-prep-session:scopes (session params)
;;   "Prepare SESSION according to the header arguments specified in PARAMS."
;;   )

;; (defun org-babel-scopes-var-to-scopes (var)
;;   "Convert an elisp var into a string of scopes source code
;; specifying a var of the same value."
;;   (format "%S" var))

;; (defun org-babel-scopes-table-or-string (results)
;;   "If the results look like a table, then convert them into an
;; Emacs-lisp table, otherwise return the results as a string."
;;   )

;; (defun org-babel-scopes-initiate-session (&optional session)
;;   "If there is not a current inferior-process-buffer in SESSION then create.
;; Return the initialized session."
;;   (unless (string= session "none")
;;     ))

(provide 'ob-scopes)
;;; ob-scopes.el ends here