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Mercurial > org > meta / babel.org

changeset 7: 4728f14839e4
parent: f747ffac7f40
child: 06698c6708de
author: Richard Westhaver <ellis@rwest.io>
date: Tue, 27 Aug 2024 21:35:44 -0400
permissions: -rw-r--r--
description: publishing updates 
     1 #+title: babel
     2 #+author: Richard Westhaver
     3 #+description: Core Library of Babel
     4 #+setupfile: ../clean.theme
     5 #+property: header-args :exports both :eval never
     6 Welcome to the CC [[https://www.gnu.org/software/emacs/manual/html_node/org/Library-of-Babel.html][Library of Babel]]. This file contains a collection of
     7 code blocks which may be used by authors throughout our public
     8 documentation.
     9 
    10 This library depends on the [[vc:comp/core][core]] being properly installed and the
    11 =core/emacs= init system loaded in emacs. See [[vc:comp/home][home]] for details.
    12 
    13 To load the library itself use ~C-c C-v i~ while visiting this file in
    14 an org-mode buffer or =org-babel-lob-ingest= from elisp.
    15 * echo                                                                 :util:
    16 #+name: echo
    17 #+begin_src emacs-lisp :var input=""
    18 input
    19 #+end_src
    20 * read                                                                   :fs:
    21 #+name: read
    22 #+begin_src emacs-lisp :var file="" :var format=""
    23 (if (string= format "csv")
    24     (with-temp-buffer
    25       (org-table-import (expand-file-name file) nil)
    26       (org-table-to-lisp))
    27   (with-temp-buffer
    28     (insert-file-contents (expand-file-name file))
    29     (buffer-string)))
    30 #+end_src
    31 * write                                                                  :fs:
    32 #+name: write
    33 #+begin_src emacs-lisp :var data="" :var file="" :var ext='()
    34 (cl-flet ((echo (r) (if (stringp r) r (format "%S" r))))
    35   (with-temp-file file
    36     (case (and (listp data)
    37                (or ext (intern (file-name-extension file))))
    38       ('tsv (insert (orgtbl-to-tsv data '(:fmt echo))))
    39       ('csv (insert (orgtbl-to-csv data '(:fmt echo))))
    40       (t    (org-babel-insert-result data)))))
    41 nil
    42 #+end_src
    43 * json                                                                 :json:
    44 #+name: json
    45 #+begin_src emacs-lisp :var file='() :var url='()
    46 (require 'json)
    47 (cond
    48  (file
    49   (org-babel-with-temp-filebuffer file
    50     (goto-char (point-min))
    51     (json-read)))
    52  (url
    53   (require 'w3m)
    54   (with-temp-buffer
    55     (w3m-retrieve url)
    56     (goto-char (point-min))
    57     (json-read))))
    58 #+end_src
    59 
    60 * headline                                                              :org:
    61 #+name: headline
    62 #+begin_src emacs-lisp :var headline="" :var file='()
    63 (save-excursion
    64   (when file (get-file-buffer file))
    65   (org-open-link-from-string (org-make-link-string headline))
    66   (save-restriction
    67     (org-narrow-to-subtree)
    68     (buffer-string)))
    69 #+end_src
    70 * transpose                                                           :table:
    71 #+name: transpose
    72 #+begin_src emacs-lisp :var table=""
    73   (apply #'mapcar #'list (list table))
    74 #+end_src
    75 * all-to-string                                                       :table:
    76 #+name: all-to-string
    77 #+begin_src emacs-lisp :var tbl='()
    78 (defun all-to-string (tbl)
    79   (if (listp tbl)
    80       (mapcar #'all-to-string tbl)
    81     (if (stringp tbl)
    82         tbl
    83       (format "%s" tbl))))
    84 (all-to-string tbl)
    85 #+end_src
    86 * systemd-list-units                                                     :os:
    87 :PROPERTIES:
    88 :ID:       3b23c98d-a286-4988-846d-2dab3d25803d
    89 :END:
    90 #+name: systemd-list-units
    91 #+begin_src sh :results replace
    92 systemctl list-units --state=running | grep -v systemd | awk '{print $1}' | grep service
    93 #+end_src
    94 
    95 * wc-dir-lines                                                           :fs:
    96 :PROPERTIES:
    97 :ID:       70008815-9634-48ca-b672-b8dcf2a44074
    98 :END:
    99 #+name: wc-dir-lines
   100 #+begin_src shell :var dir="."
   101 cd $dir && cat * | wc -l
   102 #+end_src
   103 
   104 * wc-dir-words                                                           :fs:
   105 :PROPERTIES:
   106 :ID:       be755790-f367-4654-87e5-cd2927bfef45
   107 :END:
   108 #+name: wc-dir-words
   109 #+begin_src shell :var dir="."
   110 cd $dir && cat * | wc -w
   111 #+end_src
   112 
   113 * tokei-dir-lines                                                        :fs:
   114 :PROPERTIES:
   115 :ID:       670e9855-f8d2-43eb-86af-3ef7292f90b9
   116 :END:
   117 #+name: tokei-dir-lines
   118 #+begin_src shell :var src="" :results output replace
   119   cd ~/comp/$src
   120   input=`tokei -C -o json`
   121   echo $input | jq -r '.["Total"] | .code, .comments, .blanks'
   122 #+end_src
   123 
   124 * tokei-dir-langs                                                        :fs:
   125 :PROPERTIES:
   126 :ID:       ff9682f0-bb64-427f-a87d-e0c655f9fdc9
   127 :END:
   128 #+name: tokei-dir-langs
   129 #+begin_src shell :var src="org" :results output replace
   130   cd ~/comp/$src
   131   input=`tokei -C -o json`
   132   echo $input | jq -r '.["Total"].children | keys[]'
   133 #+end_src
   134 
   135 * sum-str-nums                                                         :util:
   136 :PROPERTIES:
   137 :ID:       d3c4ac69-337f-430b-a4db-760504f099ea
   138 :END:
   139 #+name: sum-str-nums
   140 #+begin_src emacs-lisp :var s=tokei-dir-lines()
   141   (let ((tot 0))
   142     (cl-loop
   143      with tot = 0
   144      for i in (split-string s) do
   145      (setf tot (+ tot (string-to-number i)))
   146      finally return tot))
   147 #+end_src
   148 
   149 * org-task-tbl                                                          :org:
   150 :PROPERTIES:
   151 :ID:       0ee5b499-6f0b-4e15-8c6e-4876e90c20a9
   152 :END:
   153 #+name: org-task-tbl
   154 #+begin_src emacs-lisp
   155   (let* ((ast (org-element-parse-buffer)) ;; built up the abstract syntax tree of the org buffer
   156          item-types ; all occuring item types. It could be that some task has more item types than another.
   157          tasks ; accumulation list for the tasks
   158          current-task ; name of the current task (header of level 1)
   159          task-items) ; items of the current task
   160     (org-element-map ast 'headline
   161       (lambda (hl)
   162         (cl-case (org-element-property :level hl)
   163           (1 ; We assume here that headers of level 1 are tasks.
   164            (when current-task ; registering the old task
   165              (setq tasks (cons (cons current-task (nreverse task-items)) tasks)))
   166            (setq current-task (org-element-property :raw-value hl) ; preparing the new task
   167                  task-items nil))
   168           (2 ; item
   169            (let ((item-type (org-element-property :raw-value hl)))
   170              (setq item-types (cons item-type item-types))
   171              (setq task-items (cons (cons item-type (org-element-property :todo-keyword hl))
   172                                     task-items)))))))
   173     (setq tasks (nreverse (cons (cons current-task (nreverse task-items)) tasks)) ;add the last task
   174           item-types (sort (cl-remove-duplicates (nreverse item-types) :test 'string-equal) ; list of unique item types
   175                            #'string<)) ;;Sorting the items lexicographical. Other criteria could be applied.
   176       ;;;;;;;;;;
   177     ;; generating the output table:
   178     (apply
   179      #'list
   180      (cons "Item" (mapcar #'car tasks)) ; header
   181      'hline
   182      ;; rows:
   183      (mapcar
   184       ;; mapping the items to the todo states associated to the tasks:
   185       (lambda (item-type)
   186         (cons item-type
   187               (mapcar
   188                (lambda (task)
   189                  (let ((todo-status (cdr (assoc-string item-type task))))
   190                    todo-status))
   191                tasks)))
   192       item-types)))
   193 #+end_src
   194 
   195 * org-headlines-map                                                     :org:
   196 :PROPERTIES:
   197 :ID:       05955228-ca76-48bc-b769-f648b4310a9c
   198 :END:
   199 #+name: org-headlines-map
   200 #+begin_src elisp
   201   (org-element-map (org-element-parse-buffer 'headline)
   202       'headline
   203     (lambda(hl)
   204       (let ((parent (org-element-property :parent hl)))
   205         (and (eq (org-element-type parent) 'headline)
   206              (list (org-element-property :title parent) (org-element-property :title hl))))))
   207 
   208 #+end_src
   209 
   210 * make-info-tbl                                                   :org:fs:vc:
   211 :PROPERTIES:
   212 :ID:       d5ba2f3d-fc2d-4db6-8bbd-7ca440ff0e8c
   213 :END:
   214 #+name: make-info-tbl
   215 #+header: :var version="0.1.0"
   216 #+header: :var name="org"
   217 #+header: :var dir="/home/ellis/comp/"
   218 #+begin_src emacs-lisp :results table replace
   219   (let* ((src (concat dir name))
   220          (age (org-sbe "hg-log-age" ''(src name)))
   221          (rev (org-sbe "hg-rev" ''(src name)))
   222          (num (org-sbe "hg-id-num" ''(src name)))
   223          (cc1 (org-sbe "tokei-dir-lines" ''(src name)))
   224          (cc2 (org-sbe "tokei-dir-langs" ''(src name)))
   225          (nf (format "[[comp:docs/%s][%s]]" name name))
   226          (rf (format "[[vc:comp/%s][%s:%s]]" name num rev))
   227          ;; (gf (format "[[https://github.com/richardwesthaver/%s][github]]" name))
   228          (vf (format "%s" rf))
   229          (lsum (org-sbe sum-str-nums ('s 'cc1)))
   230          (l (split-string cc1))
   231          (lang (split-string cc2))
   232          (cf (format "%s = λ:%s #:%s _:%s" lsum (pop l) (pop l) (pop l))))
   233     `(hline
   234       (name ,nf)
   235       (version ,version)
   236       (vc ,vf)
   237       (updated ,age)
   238       (lines ,cf)
   239       (langs ,lang)
   240       hline))
   241   #+end_src
   242 
   243   #+RESULTS: make-info-tbl
   244   |---------+----------------------------|
   245   | name    | [[https://compiler.company/docs/org][org]]                        |
   246   | version | 0.1.0                      |
   247   | vc      | [[https://vc.compiler.company/comp/org][44+:2b6f731f3684]]           |
   248   | updated | nil                        |
   249   | lines   | 14812 = λ:13917 #:45 _:850 |
   250   | langs   | (Html Org Svg)             |
   251   |---------+----------------------------|
   252 
   253 * make-files-tbl                                                     :org:fs:
   254 :PROPERTIES:
   255 :ID:       e2ff9dcf-8340-48b8-a1a6-e0036cbcc495
   256 :END:
   257 #+name: ls-files
   258 #+begin_src sh :results silent :var dir=(expand-file-name "~/comp") name="org"
   259   ls -lh $dir/$name --time-style=long-iso \
   260     |awk '{if (NR!=1) print $8, $5, $6"-"$7}' \
   261     |awk 'BEGIN{print "file size updated"}{print $0}'
   262 #+end_src
   263 
   264 #+name: make-files-tbl
   265 #+begin_src python :var tab=ls-files() :results table :colnames yes :hlines yes :exports results :eval no-export
   266 return tab
   267 #+end_src
   268 
   269 * env-table                                                              :os:
   270 :PROPERTIES:
   271 :ID:       4c824478-0eaa-49b9-905f-2c9a6d4220eb
   272 :END:
   273 #+begin_src sh :results table replace
   274   for i in $(env);
   275   do
   276       echo "$i|" | sed '0,/=/s//|/'
   277   done
   278 #+end_src
   279 
   280 * get-env                                                                :os:
   281 :PROPERTIES:
   282 :ID:       8c1ecc68-ca25-4e72-81d8-415a43e59ae4
   283 :END:
   284 #+name: get-env
   285 #+begin_src elisp :results output :var key="HOME"
   286 (princ (getenv key))
   287 #+end_src
   288 
   289 #+RESULTS: get-env
   290 : /home/ellis
   291 
   292 * org-current-h1-title                                                  :org:
   293 :PROPERTIES:
   294 :ID:       ae61e7ed-c9ed-414c-8a5f-12b1702f018e
   295 :END:
   296 #+name: org-current-h1-title
   297 #+begin_src emacs-lisp :results value
   298   (org-element-property :title (save-excursion (org-up-heading-safe) (org-element-at-point)))
   299 #+end_src
   300 
   301 #+RESULTS: org-current-h1-title
   302 : org-current-h1-title
   303 
   304 * get-emacs-version                                                   :emacs:
   305 :PROPERTIES:
   306 :ID:       af3d83a1-31bd-41b4-be35-c1f33507fd8d
   307 :END:
   308 #+name: get-emacs-version
   309 #+begin_src elisp :results output
   310   (princ (concat (format "%s\n" (emacs-version))
   311 		 (format "Org v%s" (org-version))))
   312 #+end_src
   313 
   314 * vc-log                                                                 :vc:
   315 #+name: vc-log
   316 #+header: :var limit=-1
   317 #+header: :var buf=(buffer-name (current-buffer))
   318 #+begin_src emacs-lisp
   319 ;; Most of this code is copied from vc.el vc-print-log
   320 (require 'vc)
   321 (when (vc-find-backend-function
   322        (vc-backend (buffer-file-name (get-buffer buf))) 'print-log)
   323   (let ((limit -1)
   324         (vc-fileset nil)
   325         (backend nil)
   326         (files nil))
   327     (with-current-buffer (get-buffer buf)
   328       (setq vc-fileset (vc-deduce-fileset t)) ; FIXME: Why t? --Stef
   329       (setq backend (car vc-fileset))
   330       (setq files (cadr vc-fileset)))
   331     (with-temp-buffer
   332       (let ((status (vc-call-backend
   333                      backend 'print-log files (current-buffer))))
   334         (when (and (processp status)   ; Make sure status is a process
   335                    (= 0 (process-exit-status status))) ; which has not terminated
   336           (while (not (eq 'exit (process-status status)))
   337             (sit-for 1 t)))
   338         (buffer-string)))))
   339 #+end_src
   340 * hg-rev                                                                 :vc:
   341 :PROPERTIES:
   342 :ID:       8119cf43-f2e7-4829-939c-fc4e8531ae6c
   343 :END:
   344 #+name: hg-rev
   345 #+begin_src sh :var src="org"
   346 cd ~/comp/$src && hg log -l 1 --template '{node|short}'
   347 #+end_src
   348 
   349 #+RESULTS: hg-rev
   350 : 2b6f731f3684
   351 
   352 * hg-id-num                                                              :vc:
   353 :PROPERTIES:
   354 :ID:       9602faee-5522-445b-a568-be603e20a978
   355 :END:
   356 #+name: hg-id-num
   357 #+begin_src shell :var src="org"
   358 cd ~/comp/$src && hg id -n
   359 #+end_src
   360 
   361 #+RESULTS: hg-id-num
   362 : 36+
   363 
   364 * hg-log-age                                                             :vc:
   365 :PROPERTIES:
   366 :ID:       8492f4fb-51a6-4221-8705-a15eb5a50ed4
   367 :END:
   368 #+name: hg-log-age
   369 #+begin_src shell :var src="."
   370   cd ~/comp/$src && hg log -l1 --template "{date|age}"
   371 #+end_src
   372 
   373 #+RESULTS: hg-log-age
   374 
   375 * sh-ob-tangle                                                          :org:
   376 :PROPERTIES:
   377 :ID:       7b311df4-83a3-489d-89a0-929928bce051
   378 :END:
   379 #+name: sh-ob-tangle
   380 #+begin_src sh
   381   emacs -Q --batch --eval "
   382       (progn
   383 	(require 'ob-tangle)
   384 	(dolist (file command-line-args-left)
   385 	  (with-current-buffer (find-file-noselect file)
   386 	    (org-babel-tangle))))
   387     " "$@"
   388 #+end_src
   389 
   390 * make-dot-tree                                                         :dot:
   391 :PROPERTIES:
   392 :ID:       5588f446-2d7a-4261-b829-68effd3778ac
   393 :END:
   394 #+name: make-dot-tree
   395 #+begin_src emacs-lisp :var table=org-headlines-map() :results output
   396   (mapcar #'(lambda (x)
   397 		(princ (format "\"%s\" -> \"%s\";\n" (cl-first x) (cl-second x))))
   398 	  table)
   399 #+end_src
   400 
   401 * gen-dot-tree                                                          :dot:
   402 :PROPERTIES:
   403 :ID:       a51c943d-0f01-4c8f-96ec-db28ae7fef26
   404 :END:
   405 #+name: gen-dot-tree
   406 #+begin_src dot :file /tmp/tree.png :cmdline -Kdot -Tpng :var input=make-dot-tree() :eval no-export
   407 digraph {
   408    rankdir=TB;
   409    splines=true;
   410    node [shape=box];
   411    $input
   412   }
   413 #+end_src
   414 
   415 #+RESULTS: gen-dot-tree
   416 [[file:/tmp/tree.png]]
   417 
   418 * user-slime                                                           :lisp:
   419 :PROPERTIES:
   420 :ID:       9ffd1d10-ffad-486e-9d7d-82422342b9ff
   421 :END:
   422 #+name: user-slime
   423 #+begin_src emacs-lisp :results silent :eval no-export
   424   (unless (slime-connected-p) (slime))
   425   (slime-eval '(ql:quickload :user))
   426   (slime-eval '(cl:in-package :user))
   427 #+end_src
   428 * std-slime                                                            :lisp:
   429 :PROPERTIES:
   430 :ID:       334dae41-5c35-48bd-8368-71d79f5e48d8
   431 :END:
   432 #+name: std-slime
   433 #+begin_src emacs-lisp :results silent :eval no-export
   434   (slime)
   435   (slime-eval '(ql:quickload :std))
   436   (slime-eval '(in-package :std-user))
   437 #+end_src
   438 
   439 * cargo-update-dir                                                     :rust:
   440 :PROPERTIES:
   441 :ID:       67dc87bb-a27b-46e4-a02f-58daac514630
   442 :END:
   443 #+name: cargo-update-dir
   444 #+begin_src sh :var dir=()
   445 # update all crates in dir
   446 set -eu
   447 case $0 in
   448    (/*) dir=${0%/*}/;;
   449    (*/*) dir=./${0%/*};;
   450    (*) dir=.;;
   451 esac
   452 
   453 find "$dir/.." -name Cargo.toml -execdir cargo update \;
   454 #+end_src
   455 * rust-target-triple                                                   :rust:
   456 :PROPERTIES:
   457 :ID:       02f96ff2-c607-4889-979c-943203b8ad65
   458 :END:
   459  #+name: rust-target-triple
   460  #+begin_src shell
   461  rustc -vV | sed -n -e 's/^host: //p'
   462  #+end_src
   463 * post-align-table                                                    :table:
   464 #+NAME: post-align-tables
   465 #+header: :var text="|5|22222|\n|0||\n|12|45|\n|---\n|||\n#+TBLFM:@>$1=vsum(@1..@-1)\n\n|1|22222|\n|0||\n|12|45|\n"
   466 #+BEGIN_SRC emacs-lisp :results value :exports both
   467   (with-temp-buffer
   468     (erase-buffer)
   469     (cl-assert text nil "PostAlignTables received nil instead of text ")
   470     (insert text)
   471     (beginning-of-buffer)
   472     (org-mode)
   473     (while
   474         (search-forward-regexp org-table-any-line-regexp nil t)
   475       (org-table-align)
   476       (org-table-recalculate 'iterate)
   477       (goto-char (org-table-end)))
   478     (buffer-string))
   479 #+END_SRC
   480 * insert-table-from-file                                           :table:fs:
   481 #+NAME: insert-table-from-file
   482 #+HEADER: :var tname="table" fname="/tmp/tbl.org" newcaption="" newattr="" newname=""
   483 #+BEGIN_SRC elisp :results output drawer
   484   (let* ((klist (cl-remove-if (lambda (x) (equal (cadr x) ""))
   485     			    `(("ATTR_LATEX" ,newattr) ("CAPTION" ,newcaption) ("NAME" ,newname))))
   486          (tbl
   487           (with-temp-buffer
   488     	  (org-mode)
   489     	  (insert-file-contents fname)
   490     	  (goto-char (point-min))
   491     	  (unless (re-search-forward
   492     		   (concat "^[ \t]*#\\+\\(tbl\\)?name:[ \t]*"
   493     			   (regexp-quote tname) "[ \t]*$")
   494     		   nil t)
   495     	    (user-error "Can't find table named %s in file" tname fname))
   496     	  (forward-line 0)
   497     	  (let ((tstart (match-beginning 0))
   498     	        tend)
   499     	    (while (looking-at "^[ \t]*#\\+\\([^:]+\\): *\\(.*\\)")
   500     	      (add-to-list 'klist `(,(upcase (match-string 1)) ,(match-string 2)))
   501     	      (delete-region (point) (line-end-position))
   502     	      (kill-line))
   503     	    (unless (looking-at org-table-line-regexp)
   504     	      (looking-at "^.*$")
   505     	      (user-error "no table at location of %s, Looking-at: '%s'" tname (match-string 0)))
   506     	    (goto-char (org-table-end))
   507     	    (while (looking-at-p "^[ \t]*#\\+TBLFM:")
   508     	      (forward-line 1))
   509     	    (buffer-substring tstart (point))))))
   510     (setq klist (nreverse klist)) ;; reverse for giving priority to new user settings
   511     (dolist (elem '("NAME" "CAPTION" "ATTR_LATEX"))
   512       (when (assoc elem klist)
   513         (princ (format "#+%s: %s\n" elem (cadr (assoc elem klist))))))
   514     (princ tbl))
   515 #+END_SRC
   516 * filter-table                                                        :table:
   517 #+NAME: filter-table
   518 #+HEADER: :var tbl="" col=0 vals=""
   519 #+BEGIN_SRC elisp :results value  :colnames y
   520   (let ((lst (split-string vals)))
   521     (concatenate 'list  (loop for row in tbl
   522                               if (member (let ((field (nth col row)))
   523                                            (if (numberp field)
   524                                                (number-to-string field)
   525                                              field)) lst)
   526                               collect row into newtbl
   527                               ;; else do (princ (format "%s: %s\n" (nth col row) lst))
   528                               finally return newtbl)))
   529 #+END_SRC
   530 * filter-table-re                                                  :table:rx:
   531 #+NAME: filter-table-re
   532 #+HEADER: :var tbl="" col=0 vals=".*"
   533 #+BEGIN_SRC elisp :results value  :colnames y
   534   (let ((lst (split-string vals)))
   535     (concatenate 'list  (loop for row in tbl
   536                               if (let* ((rawfield (nth col row))
   537                                         (field (if (numberp rawfield)
   538                                                    (number-to-string rawfield)
   539                                                  rawfield)))
   540                                    (loop for regx in lst
   541                                          when(string-match-p regx field) return 't
   542                                          finally return nil))
   543                               collect row into newtbl
   544                               ;; else do (princ (format "%s: %s\n" (nth col row) lst))
   545                               finally return newtbl)))
   546 #+END_SRC
   547 * group-table                                                         :table:
   548 #+NAME: group-table
   549 #+HEADER: :var tbl="" grp="Name" op="sum" rescols="B"
   550 #+BEGIN_SRC python :results output verbatim drawer :colnames no
   551   import pandas as pd
   552   import numpy as np
   553   import orgbabelhelper as obh
   554   import sys
   555   import re
   556 
   557   df = obh.orgtable_to_dataframe(tbl)
   558   grparr = re.split(r",\s*", grp)
   559   #print re.split(r",\s*", rescols) + [grp]
   560   df = df[re.split(r",\s*", rescols) + grparr]
   561   for elem in grparr:
   562       assert elem in df.columns, "Error: group column %s not in table columns %s" % (elem, ",".join(df.columns))
   563 
   564   if op == "sum":
   565       res = df.groupby(grparr).sum()
   566   else:
   567       error("operation %s not implemented" % op)
   568       sys.exit(1)
   569 
   570   print(obh.dataframe_to_orgtable(res))
   571 
   572 #+END_SRC
   573 * insert-file                                                            :fs:
   574 #+NAME: lobInsertFile
   575 #+HEADER: :var filename="/tmp/foo"
   576 #+begin_src elisp :results value raw drawer
   577   (cl-labels ((wrap-src
   578   	      (lang)
   579   	      (list (format "#+BEGIN_SRC %s :eval never :exports source\n" lang)
   580                       "#+END_SRC\n")))
   581     (let ((wrappers
   582   	 (pcase (file-name-extension filename)
   583   	   ("py" (wrap-src "python"))
   584   	   (".el" (wrap-src "emacs-lisp"))
   585   	   (t '("#+BEGIN_EXAMPLE\n" "#+END_EXAMPLE\n")))))
   586       (with-temp-buffer
   587         (goto-char (point-min))
   588         (insert (format-time-string "# inserted at %Y-%m-%d %H:%M:%S\n"))
   589         (insert (car wrappers))
   590         (insert-file-contents filename)
   591         (goto-char (point-max))
   592         (insert (car (cdr wrappers)))
   593         (buffer-string))))
   594 #+end_src