lisp/ob-perl.el

   1 ;;; ob-perl.el --- org-babel functions for perl evaluation
   2
   3 ;; Copyright (C) 2009-2013 Free Software Foundation, Inc.
   4
   5 ;; Authors: Dan Davison
   6 ;;       Eric Schulte
   7 ;; Keywords: literate programming, reproducible research
   8 ;; Homepage: http://orgmode.org
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs 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 of the License, or
  15 ;; (at your option) any later version.
  16
  17 ;; GNU Emacs 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.  If not, see <http://www.gnu.org/licenses/>.
  24
  25 ;;; Commentary:
  26
  27 ;; Org-Babel support for evaluating perl source code.
  28
  29 ;;; Code:
  30 (require 'ob)
  31 (eval-when-compile (require 'cl))
  32
  33 (defvar org-babel-tangle-lang-exts)
  34 (add-to-list 'org-babel-tangle-lang-exts '("perl" . "pl"))
  35
  36 (defvar org-babel-default-header-args:perl '())
  37
  38 (defvar org-babel-perl-command "perl"
  39   "Name of command to use for executing perl code.")
  40
  41 (defun org-babel-execute:perl (body params)
  42   "Execute a block of Perl code with Babel.
  43 This function is called by `org-babel-execute-src-block'."
  44   (let* ((session (cdr (assoc :session params)))
  45          (result-params (cdr (assoc :result-params params)))
  46          (result-type (cdr (assoc :result-type params)))
  47          (full-body (org-babel-expand-body:generic
  48                      body params (org-babel-variable-assignments:perl params)))
  49          (session (org-babel-perl-initiate-session session)))
  50     (org-babel-reassemble-table
  51      (org-babel-perl-evaluate session full-body result-type result-params)
  52      (org-babel-pick-name
  53       (cdr (assoc :colname-names params)) (cdr (assoc :colnames params)))
  54      (org-babel-pick-name
  55       (cdr (assoc :rowname-names params)) (cdr (assoc :rownames params))))))
  56
  57 (defun org-babel-prep-session:perl (session params)
  58   "Prepare SESSION according to the header arguments in PARAMS."
  59   (error "Sessions are not supported for Perl"))
  60
  61 (defun org-babel-variable-assignments:perl (params)
  62   "Return list of perl statements assigning the block's variables."
  63   (mapcar
  64    (lambda (pair)
  65      (org-babel-perl--var-to-perl (cdr pair) (car pair)))
  66    (mapcar #'cdr (org-babel-get-header params :var))))
  67
  68 ;; helper functions
  69
  70 (defvar org-babel-perl-var-wrap "q(%s)"
  71   "Wrapper for variables inserted into Perl code.")
  72
  73 (defvar org-babel-perl--lvl)
  74 (defun org-babel-perl--var-to-perl (var &optional varn)
  75   "Convert an elisp value to a perl variable.
  76 The elisp value, VAR, is converted to a string of perl source code
  77 specifying a var of the same value."
  78   (if varn
  79       (let ((org-babel-perl--lvl 0) (lvar (listp var)) prefix)
  80         (concat "my $" (symbol-name varn) "=" (when lvar "\n")
  81                 (org-babel-perl--var-to-perl var)
  82                 ";\n"))
  83     (let ((prefix (make-string (* 2 org-babel-perl--lvl) ?\ )))
  84       (concat prefix
  85               (if (listp var)
  86                   (let ((org-babel-perl--lvl (1+ org-babel-perl--lvl)))
  87                     (concat "[\n"
  88                             (mapconcat #'org-babel-perl--var-to-perl var "")
  89                             prefix "]"))
  90                 (format "q(%s)" var))
  91               (unless (zerop org-babel-perl--lvl) ",\n")))))
  92
  93 (defvar org-babel-perl-buffers '(:default . nil))
  94
  95 (defun org-babel-perl-initiate-session (&optional session params)
  96   "Return nil because sessions are not supported by perl."
  97   nil)
  98
  99 (defvar org-babel-perl-wrapper-method "{
 100     my $babel_sub = sub {
 101         %s
 102     };
 103     open my $BOH, qq(>%s) or die qq(Perl: Could not open output file.$/);
 104     my $rv = &$babel_sub();
 105     my $rt = ref $rv;
 106     select $BOH;
 107     if (qq(ARRAY) eq $rt) {
 108         local $\\=$/;
 109         local $,=qq(\t);
 110         foreach my $rv ( @$rv ) {
 111             my $rt = ref $rv;
 112             if (qq(ARRAY) eq $rt) {
 113                 print @$rv;
 114             } else {
 115                 print $rv;
 116             }
 117         }
 118     } else {
 119         print $rv;
 120     }
 121 }")
 122
 123 (defvar org-babel-perl-preface nil)
 124
 125 (defvar org-babel-perl-pp-wrapper-method
 126   nil)
 127
 128 (defun org-babel-perl-evaluate (session ibody &optional result-type result-params)
 129   "Pass BODY to the Perl process in SESSION.
 130 If RESULT-TYPE equals 'output then return a list of the outputs
 131 of the statements in BODY, if RESULT-TYPE equals 'value then
 132 return the value of the last statement in BODY, as elisp."
 133   (when session (error "Sessions are not supported for Perl"))
 134   (let* ((body (concat org-babel-perl-preface ibody))
 135          (tmp-file (org-babel-temp-file "perl-"))
 136          (tmp-babel-file (org-babel-process-file-name
 137                           tmp-file 'noquote)))
 138     ((lambda (results)
 139        (when results
 140          (org-babel-result-cond result-params
 141            (org-babel-eval-read-file tmp-file)
 142            (org-babel-import-elisp-from-file tmp-file '(16)))))
 143      (case result-type
 144        (output
 145         (with-temp-file tmp-file
 146           (insert
 147            (org-babel-eval org-babel-perl-command body))
 148           (buffer-string)))
 149        (value
 150         (org-babel-eval org-babel-perl-command
 151                         (format org-babel-perl-wrapper-method
 152                                 body tmp-babel-file)))))))
 153
 154 (provide 'ob-perl)
 155
 156
 157
 158 ;;; ob-perl.el ends here