contrib/babel/lisp/langs/org-babel-haskell.el

   1 ;;; org-babel-haskell.el --- org-babel functions for haskell evaluation
   2
   3 ;; Copyright (C) 2009 Eric Schulte
   4
   5 ;; Author: Eric Schulte
   6 ;; Keywords: literate programming, reproducible research
   7 ;; Homepage: http://orgmode.org
   8 ;; Version: 0.01
   9
  10 ;;; License:
  11
  12 ;; This program is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 3, or (at your option)
  15 ;; any later version.
  16 ;;
  17 ;; This program is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21 ;;
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  25 ;; Boston, MA 02110-1301, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; Org-Babel support for evaluating haskell source code.  This one will
  30 ;; be sort of tricky because haskell programs must be compiled before
  31 ;; they can be run, but haskell code can also be run through an
  32 ;; interactive interpreter.
  33 ;;
  34 ;; For now lets only allow evaluation using the haskell interpreter.
  35
  36 ;;; Requirements:
  37
  38 ;; - haskell-mode :: http://www.iro.umontreal.ca/~monnier/elisp/#haskell-mode
  39 ;;
  40 ;; - inf-haskell :: http://www.iro.umontreal.ca/~monnier/elisp/#haskell-mode
  41 ;;
  42 ;; - (optionally) lhs2tex :: http://people.cs.uu.nl/andres/lhs2tex/
  43
  44 ;;; Code:
  45 (require 'org-babel)
  46 (require 'haskell-mode)
  47 (require 'inf-haskell)
  48
  49 (org-babel-add-interpreter "haskell")
  50
  51 (add-to-list 'org-babel-tangle-langs '("haskell" "hs"))
  52
  53 (defvar org-babel-haskell-lhs2tex-command "lhs2tex")
  54
  55 (defvar org-babel-haskell-eoe "\"org-babel-haskell-eoe\"")
  56
  57 (defun org-babel-execute:haskell (body params)
  58   "Execute a block of Haskell code with org-babel.  This function
  59 is called by `org-babel-execute-src-block' with the following
  60 variables pre-set using `multiple-value-bind'.
  61
  62   (session vars result-params result-type)"
  63   (message "executing haskell source code block")
  64   (let* ((full-body (concat
  65                      (mapconcat
  66                       (lambda (pair) (format "let %s = %s;" (car pair) (cdr pair)))
  67                       vars "\n") "\n" body "\n"))
  68          (session (org-babel-prep-session:haskell session params))
  69          (raw (org-babel-comint-with-output session org-babel-haskell-eoe t
  70                 (insert (org-babel-trim full-body))
  71                 (comint-send-input nil t)
  72                 (insert org-babel-haskell-eoe)
  73                 (comint-send-input nil t)))
  74          (results (mapcar
  75                    #'org-babel-haskell-read-string
  76                    (cdr (member org-babel-haskell-eoe
  77                                 (reverse (mapcar #'org-babel-trim raw)))))))
  78     (case result-type
  79       (output (mapconcat #'identity (reverse (cdr results)) "\n"))
  80       (value (org-babel-haskell-table-or-string (car results))))))
  81
  82 (defun org-babel-haskell-read-string (string)
  83   "Strip \\\"s from around haskell string"
  84   (if (string-match "\"\\([^\000]+\\)\"" string)
  85       (match-string 1 string)
  86     string))
  87
  88 (defun org-babel-haskell-initiate-session (&optional session)
  89   "If there is not a current inferior-process-buffer in SESSION
  90 then create.  Return the initialized session."
  91   ;; TODO: make it possible to have multiple sessions
  92   (run-haskell) (current-buffer))
  93
  94 (defun org-babel-load-session:haskell (session body params)
  95   "Load BODY into SESSION."
  96   (save-window-excursion
  97     (let* ((buffer (org-babel-prep-session:haskell session params))
  98            (load-file (concat (make-temp-file "org-babel-haskell-load") ".hs")))
  99       (with-temp-buffer
 100         (insert body) (write-file load-file)
 101         (haskell-mode) (inferior-haskell-load-file))
 102       buffer)))
 103
 104 (defun org-babel-prep-session:haskell (session params)
 105   "Prepare SESSION according to the header arguments specified in PARAMS."
 106   (save-window-excursion
 107     (org-babel-haskell-initiate-session session)
 108     (let* ((vars (org-babel-ref-variables params))
 109            (var-lines (mapconcat ;; define any variables
 110                        (lambda (pair)
 111                          (format "%s=%s"
 112                                  (car pair)
 113                                  (org-babel-ruby-var-to-ruby (cdr pair))))
 114                        vars "\n"))
 115            (vars-file (concat (make-temp-file "org-babel-haskell-vars") ".hs")))
 116       (when vars
 117         (with-temp-buffer
 118           (insert var-lines) (write-file vars-file)
 119           (haskell-mode) (inferior-haskell-load-file)))
 120       (current-buffer))))
 121
 122 (defun org-babel-haskell-table-or-string (results)
 123   "If the results look like a table, then convert them into an
 124 Emacs-lisp table, otherwise return the results as a string."
 125   (org-babel-read
 126    (if (and (stringp results) (string-match "^\\[.+\\]$" results))
 127        (org-babel-read
 128         (replace-regexp-in-string
 129          "\\[" "(" (replace-regexp-in-string
 130                     "\\]" ")" (replace-regexp-in-string
 131                                "," " " (replace-regexp-in-string
 132                                          "'" "\"" results)))))
 133      results)))
 134
 135 (defun org-babel-haskell-export-to-lhs ()
 136   "Export to a .lhs with all haskell code blocks escaped
 137 appropriately, then process the resulting .lhs file using
 138 lhs2tex.  This function will create two new files, base-name.lhs
 139 and base-name.tex where base-name is the name of the current
 140 org-mode file.
 141
 142 Note that all standard org-babel literate programming
 143 constructs (header arguments, no-web syntax etc...) are ignored."
 144   (interactive)
 145   (let* ((contents (buffer-string))
 146          (haskell-regexp
 147           (concat "^\\([ \t]*\\)#\\+begin_src[ \t]haskell*\\(.*\\)?[\r\n]"
 148                   "\\([^\000]*?\\)[\r\n][ \t]*#\\+end_src.*"))
 149          (base-name (file-name-sans-extension (buffer-file-name)))
 150          (tmp-file (make-temp-file "ob-haskell"))
 151          (tmp-org-file (concat tmp-file ".org"))
 152          (tmp-tex-file (concat tmp-file ".tex"))
 153          (lhs-file (concat base-name ".lhs"))
 154          (tex-file (concat base-name ".tex"))
 155          (command (concat org-babel-haskell-lhs2tex-command " " lhs-file " > " tex-file))
 156          indentation)
 157     ;; escape haskell source-code blocks
 158     (with-temp-file tmp-org-file
 159       (insert contents)
 160       (goto-char (point-min))
 161       (while (re-search-forward haskell-regexp nil t)
 162         (save-match-data (setq indentation (length (match-string 1))))
 163         (replace-match (save-match-data (concat
 164                                          "#+begin_latex\n\\begin{code}\n"
 165                                          (org-remove-indentation (match-string 3))
 166                                          "\n\\end{code}\n#+end_latex\n"))
 167                        t t)
 168         (indent-code-rigidly (match-beginning 0) (match-end 0) indentation)))
 169     (save-excursion
 170       ;; export to latex w/org and save as .lhs
 171       (find-file tmp-org-file) (call-interactively 'org-export-as-latex)
 172       (kill-buffer)
 173       (delete-file tmp-org-file)
 174       (find-file tmp-tex-file)
 175       (goto-char (point-min)) (forward-line 2)
 176       (insert "%include polycode.fmt\n")
 177       ;; ensure all \begin/end{code} statements start at the first column
 178       (while (re-search-forward "^[ \t]+\\\\begin{code}[^\000]+\\\\end{code}" nil t)
 179         (replace-match (save-match-data (org-remove-indentation (match-string 0)))
 180                        t t))
 181       (setq contents (buffer-string))
 182       (save-buffer) (kill-buffer))
 183     (delete-file tmp-tex-file)
 184     ;; save org exported latex to a .lhs file
 185     (with-temp-file lhs-file (insert contents))
 186     ;; process .lhs file with lhs2tex
 187     (message "running %s" command) (shell-command command)))
 188
 189 (provide 'org-babel-haskell)
 190 ;;; org-babel-haskell.el ends here