lisp/ob-scala.el

   1 ;;; ob-scala.el --- org-babel functions for Scala evaluation
   2
   3 ;; Copyright (C) 2012  Free Software Foundation, Inc.
   4
   5 ;; Author: Andrzej Lichnerowicz
   6 ;; Keywords: literate programming, reproducible research
   7 ;; Homepage: http://orgmode.org
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25 ;; Currently only supports the external execution.  No session support yet.
  26
  27 ;;; Requirements:
  28 ;; - Scala language :: http://www.scala-lang.org/
  29 ;; - Scala major mode :: Can be installed from Scala sources
  30 ;;  https://github.com/scala/scala-dist/blob/master/tool-support/src/emacs/scala-mode.el
  31
  32 ;;; Code:
  33 (require 'ob)
  34 (require 'ob-ref)
  35 (require 'ob-comint)
  36 (require 'ob-eval)
  37 (eval-when-compile (require 'cl))
  38
  39 (defvar org-babel-tangle-lang-exts) ;; Autoloaded
  40 (add-to-list 'org-babel-tangle-lang-exts '("scala" . "scala"))
  41 (defvar org-babel-default-header-args:scala '())
  42 (defvar org-babel-scala-command "scala"
  43   "Name of the command to use for executing Scala code.")
  44
  45 (defun org-babel-execute:scala (body params)
  46   "Execute a block of Scala code with org-babel.  This function is
  47 called by `org-babel-execute-src-block'"
  48   (message "executing Scala source code block")
  49   (let* ((processed-params (org-babel-process-params params))
  50          (session (org-babel-scala-initiate-session (nth 0 processed-params)))
  51          (vars (nth 1 processed-params))
  52          (result-params (nth 2 processed-params))
  53          (result-type (cdr (assoc :result-type params)))
  54          (full-body (org-babel-expand-body:generic
  55                      body params))
  56          (result (org-babel-scala-evaluate
  57                   session full-body result-type result-params)))
  58
  59     (org-babel-reassemble-table
  60      result
  61      (org-babel-pick-name
  62       (cdr (assoc :colname-names params)) (cdr (assoc :colnames params)))
  63      (org-babel-pick-name
  64       (cdr (assoc :rowname-names params)) (cdr (assoc :rownames params))))))
  65
  66
  67 (defun org-babel-scala-table-or-string (results)
  68   "Convert RESULTS into an appropriate elisp value.
  69 If RESULTS look like a table, then convert them into an
  70 Emacs-lisp table, otherwise return the results as a string."
  71   (org-babel-script-escape results))
  72
  73
  74 (defvar org-babel-scala-wrapper-method
  75
  76 "var str_result :String = null;
  77
  78 Console.withOut(new java.io.OutputStream() {def write(b: Int){
  79 }}) {
  80   str_result = {
  81 %s
  82   }.toString
  83 }
  84
  85 print(str_result)
  86 ")
  87
  88
  89 (defun org-babel-scala-evaluate
  90   (session body &optional result-type result-params)
  91   "Evaluate BODY in external Scala process.
  92 If RESULT-TYPE equals 'output then return standard output as a string.
  93 If RESULT-TYPE equals 'value then return the value of the last statement
  94 in BODY as elisp."
  95   (when session (error "Sessions are not (yet) supported for Scala"))
  96   (case result-type
  97     (output
  98      (let ((src-file (org-babel-temp-file "scala-")))
  99        (progn (with-temp-file src-file (insert body))
 100               (org-babel-eval
 101                (concat org-babel-scala-command " " src-file) ""))))
 102     (value
 103      (let* ((src-file (org-babel-temp-file "scala-"))
 104             (wrapper (format org-babel-scala-wrapper-method body)))
 105        (with-temp-file src-file (insert wrapper))
 106        ((lambda (raw)
 107           (if (member "code" result-params)
 108               raw
 109             (org-babel-scala-table-or-string raw)))
 110         (org-babel-eval
 111          (concat org-babel-scala-command " " src-file) ""))))))
 112
 113
 114 (defun org-babel-prep-session:scala (session params)
 115   "Prepare SESSION according to the header arguments specified in PARAMS."
 116   (error "Sessions are not (yet) supported for Scala"))
 117
 118 (defun org-babel-scala-initiate-session (&optional session)
 119   "If there is not a current inferior-process-buffer in SESSION
 120 then create.  Return the initialized session.  Sessions are not
 121 supported in Scala."
 122   nil)
 123
 124 (provide 'ob-scala)
 125
 126
 127
 128 ;;; ob-scala.el ends here