Re: [Orgmode] [BUG] #+begin_src wo. language blocks XHTML export

[Eric Schulte]

Carsten Dominik <address@hidden> writes:

> On Jul 12, 2010, at 10:13 AM, David Maus wrote:
>
>> SEric Schulte wrote:
>>> "Thomas S. Dye" <address@hidden> writes:
>>
>>>> On Jul 8, 2010, at 9:09 AM, Eric Schulte wrote:
>>>>
>>>>> Sebastian Rose <address@hidden> writes:
>>>>>
>>>>> [...]
>>>>>>
>>>>>> It can be considered an error, since the docs say:
>>>>>>
>>>>>> "...This is done with the ‘src’ block, where you also need to
>>>>>> specify the name of the major mode that should be used to fontify
>>>>>> the example..."
>>>>>>
>>>>>
>>>>> I would vote that this be considered an error as a source block
>>>>> doesn't make sense w/o a source language.  If others agree with
>>>>> this
>>>>> interpretation, I would be happy to submit a patch which actively
>>>>> raises an errors when this cases is encountered.
>>>>>
>>>>> Cheers -- Eric
>>>>
>>>> This seems like the right approach to me.
>>>>
>>>> Tom
>>
>>> As promised here's a patch which raises errors when source blocks
>>> don't
>>> have a specified language.  I would prefer if the error could
>>> indicate
>>> which block caused the problem, but I don't know how to accomplish
>>> this.
>>
>> Maybe we could store a marker in a text property of (source) blocks
>> right before they are processed in the input file?
>
> The problem here is that during export, the source code is taken
> from a temporary buffer containing an already modifed copy of the
> original buffer.
>
> Another solution would be to include into the message is short
> part of the code itself (maybe the first line...) - this should
> make it possible to identify the problematic block reasonably easily.
>
> - Carsten

The following updated patch includes the first line (up to 35
characters) of the code block in the error message.

-- Eric

>From a76629a565920c3506f7046cc15d27ad01b8bd47 Mon Sep 17 00:00:00 2001
From: Eric Schulte <address@hidden>
Date: Mon, 12 Jul 2010 10:42:59 -0700
Subject: [PATCH] org-exp: raise an error when trying to export code blocks w/o 
languages

* lisp/ob.el (org-babel-get-src-block-info): ensure that we don't
  match (and return info for) source blocks without a language

* lisp/org-exp.el (org-export-replace-src-segments-and-examples):
  updated source code block regexp so that the presence of a language
  can be explicitly checked.  Also now raising an error when a source
  block does not have a language.
---
 lisp/ob.el      |    3 ++-
 lisp/org-exp.el |   30 ++++++++++++++++++++----------
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/lisp/ob.el b/lisp/ob.el
index 7b7be3d..d94cc06 100644
--- a/lisp/ob.el
+++ b/lisp/ob.el
@@ -143,7 +143,8 @@ added to the header-arguments-alist."
          (setq indent (car (last info)))
          (setq info (butlast info))
          (forward-line -1)
-         (if (looking-at org-babel-src-name-w-name-regexp)
+         (if (and (looking-at org-babel-src-name-w-name-regexp)
+                  (match-string 2))
              (progn
                (setq info (append info (list (org-babel-clean-text-properties
                                               (match-string 2)))))
diff --git a/lisp/org-exp.el b/lisp/org-exp.el
index f1cea62..55b8812 100644
--- a/lisp/org-exp.el
+++ b/lisp/org-exp.el
@@ -2107,19 +2107,29 @@ in the list) and remove property and value from the 
list in LISTVAR."
        lang code trans opts indent caption)
     (goto-char (point-min))
     (while (re-search-forward
-           "\\(^\\([ \t]*\\)#\\+BEGIN_SRC:?[ \t]+\\([^ 
\t\n]+\\)\\(.*\\)\n\\([^\000]+?\n\\)[ \t]*#\\+END_SRC.*\n?\\)\\|\\(^\\([ 
\t]*\\)#\\+BEGIN_EXAMPLE:?\\(?:[ \t]+\\(.*\\)\\)?\n\\([^\000]+?\n\\)[ 
\t]*#\\+END_EXAMPLE.*\n?\\)"
+           "\\(^\\([ \t]*\\)#\\+BEGIN_SRC:?\\([ \t]+\\([^ 
\t\n]+\\)\\)?\\(.*\\)\n\\([^\000]+?\n\\)[ \t]*#\\+END_SRC.*\n?\\)\\|\\(^\\([ 
\t]*\\)#\\+BEGIN_EXAMPLE:?\\(?:[ \t]+\\(.*\\)\\)?\n\\([^\000]+?\n\\)[ 
\t]*#\\+END_EXAMPLE.*\n?\\)"
            nil t)
       (if (match-end 1)
-         ;; src segments
-         (setq lang (match-string 3)
-               opts (match-string 4)
-               code (match-string 5)
-               indent (length (match-string 2))
-                caption (get-text-property 0 'org-caption (match-string 0)))
+         (if (not (match-string 4))
+             (error "source block missing language specification: %s"
+                    (let* ((body (match-string 6))
+                           (nothing (message "body:%s" body))
+                           (preview (or (and (string-match
+                                              "^[ \t]*\\([^\n\r]*\\)" body)
+                                             (match-string 1 body)) body)))
+                      (if (> (length preview) 35)
+                          (concat (substring preview 0 32) "...")
+                        preview)))
+           ;; src segments
+           (setq lang (match-string 4)
+                 opts (match-string 5)
+                 code (match-string 6)
+                 indent (length (match-string 2))
+                 caption (get-text-property 0 'org-caption (match-string 0))))
        (setq lang nil
-             opts (match-string 8)
-             code (match-string 9)
-             indent (length (match-string 7))
+             opts (match-string 9)
+             code (match-string 10)
+             indent (length (match-string 8))
               caption (get-text-property 0 'org-caption (match-string 0))))
 
       (setq trans (org-export-format-source-code-or-example
-- 
1.7.0.4