lisp/ob-calc.el

   1 ;;; ob-calc.el --- Babel Functions for Calc          -*- lexical-binding: t; -*-
   2
   3 ;; Copyright (C) 2010-2018 Free Software Foundation, Inc.
   4
   5 ;; Author: Eric Schulte
   6 ;; Keywords: literate programming, reproducible research
   7 ;; Homepage: https://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 <https://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; Org-Babel support for evaluating calc code
  27
  28 ;;; Code:
  29 (require 'ob)
  30 (require 'calc)
  31 (require 'calc-trail)
  32 (require 'calc-store)
  33
  34 (declare-function calc-store-into    "calc-store" (&optional var))
  35 (declare-function calc-recall        "calc-store" (&optional var))
  36 (declare-function math-evaluate-expr "calc-ext"   (x))
  37 (declare-function org-trim "org" (s &optional keep-lead))
  38
  39 (defvar org-babel-default-header-args:calc nil
  40   "Default arguments for evaluating a calc source block.")
  41
  42 (defun org-babel-expand-body:calc (body _params)
  43   "Expand BODY according to PARAMS, return the expanded body." body)
  44
  45 (defvar org--var-syms) ; Dynamically scoped from org-babel-execute:calc
  46
  47 (defun org-babel-execute:calc (body params)
  48   "Execute a block of calc code with Babel."
  49   (unless (get-buffer "*Calculator*")
  50     (save-window-excursion (calc) (calc-quit)))
  51   (let* ((vars (org-babel--get-vars params))
  52          (org--var-syms (mapcar #'car vars))
  53          (var-names (mapcar #'symbol-name org--var-syms)))
  54     (mapc
  55      (lambda (pair)
  56        (calc-push-list (list (cdr pair)))
  57        (calc-store-into (car pair)))
  58      vars)
  59     (mapc
  60      (lambda (line)
  61        (when (> (length line) 0)
  62          (cond
  63           ;; simple variable name
  64           ((member line var-names) (calc-recall (intern line)))
  65           ;; stack operation
  66           ((string= "'" (substring line 0 1))
  67            (funcall (lookup-key calc-mode-map (substring line 1)) nil))
  68           ;; complex expression
  69           (t
  70            (calc-push-list
  71             (list (let ((res (calc-eval line)))
  72                     (cond
  73                      ((numberp res) res)
  74                      ((math-read-number res) (math-read-number res))
  75                      ((listp res) (error "Calc error \"%s\" on input \"%s\""
  76                                          (cadr res) line))
  77                      (t (replace-regexp-in-string
  78                          "'" ""
  79                          (calc-eval
  80                           (math-evaluate-expr
  81                            ;; resolve user variables, calc built in
  82                            ;; variables are handled automatically
  83                            ;; upstream by calc
  84                            (mapcar #'org-babel-calc-maybe-resolve-var
  85                                    ;; parse line into calc objects
  86                                    (car (math-read-exprs line)))))))))
  87                   ))))))
  88      (mapcar #'org-trim
  89              (split-string (org-babel-expand-body:calc body params) "[\n\r]"))))
  90   (save-excursion
  91     (with-current-buffer (get-buffer "*Calculator*")
  92       (prog1
  93         (calc-eval (calc-top 1))
  94         (calc-pop 1)))))
  95
  96 (defun org-babel-calc-maybe-resolve-var (el)
  97   (if (consp el)
  98       (if (and (eq 'var (car el)) (member (cadr el) org--var-syms))
  99           (progn
 100             (calc-recall (cadr el))
 101             (prog1 (calc-top 1)
 102               (calc-pop 1)))
 103         (mapcar #'org-babel-calc-maybe-resolve-var el))
 104     el))
 105
 106 (provide 'ob-calc)
 107
 108
 109
 110 ;;; ob-calc.el ends here