hmm.. I don't know if it was a bug, I ran the code on my system before sending it, and it worked for me ;) I am glad you figured it out on your system.

you could avoid the double if statements like this:

(defun my-exp-headings-to-markdown ()
  "Export each top-level heading to markdown."
  (interactive)
  (org-map-entries
   (lambda ()
     (let ((level (nth 1 (org-heading-components)))
           (title (nth 4 (org-heading-components))))
       (when (= level 1)
         (org-entry-put (point) "EXPORT_FILE_NAME" title)
         (org-md-export-to-markdown nil 1 nil)))))
   nil nil))


The when macro is like an if macro, with no else body.

John

-----------------------------------
John Kitchin
Associate Professor
Doherty Hall A207F
Department of Chemical Engineering
Carnegie Mellon University
Pittsburgh, PA 15213
412-268-7803
http://kitchingroup.cheme.cmu.edu



On Sun, Jan 5, 2014 at 2:49 PM, Ista Zahn <istazahn@gmail.com> wrote:
On Sun, Jan 5, 2014 at 8:40 AM, John Kitchin <jkitchin@andrew.cmu.edu> wrote:
> Try this:
>
>
> (org-map-entries
>              (lambda ()
>                (let ((level (nth 1 (org-heading-components)))
>                      (title (nth 4 (org-heading-components))))
>                  (if (= level 1)
>                      (org-entry-put (point) ":EXPORT_FILE_NAME:" title))))
>  nil nil)
>
> It seems to do what you want.

Dear John,

Thank you thank you! Using your code as I template I managed to write
a function that does what I wanted:

(defun my-exp-headings-to-markdown ()
  "Export each top-level heading to markdown."
  (interactive)
  (org-map-entries
   (lambda ()
     (let ((level (nth 1 (org-heading-components)))
  (title (nth 4 (org-heading-components))))
       (if (= level 1)
  (org-entry-put (point) "EXPORT_FILE_NAME" title))
       (if (= level 1)
  (org-md-export-to-markdown nil 1 nil))))
   nil nil))

Note that I had to remove the ":" from the second argument to
"org-entry-put" to get it working properly on my system. Not sure if
that was a bug in your original example or not.

Best,
Ista

>
> John
>
> -----------------------------------
> John Kitchin
> Associate Professor
> Doherty Hall A207F
> Department of Chemical Engineering
> Carnegie Mellon University
> Pittsburgh, PA 15213
> 412-268-7803
> http://kitchingroup.cheme.cmu.edu
>
>
>
> On Sat, Jan 4, 2014 at 7:36 PM, Ista Zahn <istazahn@gmail.com> wrote:
>>
>> On Sat, Jan 4, 2014 at 6:41 PM, Alan L Tyree <alantyree@gmail.com> wrote:
>> > On 05/01/14 09:45, Charles Millar wrote:
>> >>
>> >> Ista and all,
>> >>
>> >> On 1/4/2014 5:29 PM, Ista Zahn wrote:
>> >>>
>> >>> Hi all,
>> >>>
>> >>> I'm looking for a way to export each top-level heading to a separate
>> >>> markdown file. Ideally I would like to have the exported files named
>> >>> according to the heading. For example I would like this org file
>> >>>
>> >>> -----------------------------------
>> >>> * Section one
>> >>> Section one text
>> >>> * Section two
>> >>> ** Section two a
>> >>> Section two text
>> >>> * Section three
>> >>> Section three text
>> >>> -----------------------------------
>> >>>
>> >>> To generate three files:
>> >>>
>> >>> --- Section one.md ---
>> >>> Section one text
>> >>>
>> >>> -----------------------------------
>> >>>
>> >>> --- Section two.md---
>> >>> ## Section two a
>> >>>
>> >>> Section two text
>> >>>
>> >>> -----------------------------------
>> >>>
>> >>> --- Section three.md -
>> >>> # Section three
>> >>>
>> >>> Section three text
>> >>>
>> >>> -----------------------------------
>> >>>
>> >>> I suspect that the publishing framework might support this, but I've
>> >>> thus far avoided it because it looks pretty complicated to set up.
>> >>> Before I dive in I'd like to know if the publishing framework is the
>> >>> correct place to look for this functionality or if there is an easier
>> >>> way to do it.
>> >>>
>> >>>
>> >>
>> >> I have a similar question regarding LaTeX export. How to export a
>> >> heading
>> >> (any heading, regardless of level) within a file to heading.tex instead
>> >> of
>> >> file.tex? So far the only solution I have cobbled together is to C-x
>> >> C-f
>> >> 'file.tex" and then C-x C-w "heading.tex" .  I then typeset heading.tex
>> >> using TeXworks. Perhaps I should note that my exported heading is
>> >> tagged so
>> >> that the heading is ignored.
>> >>
>> >> Charlie Millar
>> >>
>> >> ---
>> >> This email is free from viruses and malware because avast! Antivirus
>> >> protection is active.
>> >> http://www.avast.com
>> >>
>> >>
>> >>
>> > Use properties to set the export file name -- example:
>> >   :PROPERTIES:
>> >   :EXPORT_TITLE: Internet banking fraud
>> >   :EXPORT_FILE_NAME: internet-fraud
>> >   :EXPORT_AUTHOR: Alan L Tyree
>> >   :Citation: (2011) 22 JBFLP 214
>> >   :EXPORT_OPTIONS: num:nil toc:nil
>> >   :END:
>>
>> Thanks, gets me half the way there. Setting properties as you
>> described and exporting each sub-tree works properly. Now how can I do
>> this for all the top-level headings in a file?
>>
>> Best,
>> Ista
>>
>> >
>> > If I understood your question properly.
>> >
>> > Cheers,
>> > Alan
>> >
>> >
>> >
>> > --
>> > Alan L Tyree                    http://www2.austlii.edu.au/~alan
>> > Tel:  04 2748 6206              sip:typhoon@iptel.org
>> >
>> >
>>
>