Problems with hyperlinked files

Problems with hyperlinked files

[Leo Alekseyev]

Hi all,
I am unable to open locally linked files if I use angle brackets to
protect spaces, like so:

   [[<file:E:\ebooks\math\Probability and statistics\The Elements of
Statistical Learning (2nd ed).pdf>][Hastie et al]]

-- the echo area displays "no such file: E:\ebooks\math\Probability
and statistics\The Elements of Statistical Learning (2nd ed).pdf>"
<---- note the right angle bracket here.  Generally, any file links
with angle brackets refuse to open.  Is this a known bug?...  is there
a patch?..  (Org mode 6.31a, emacs 23.1)

Re: Problems with hyperlinked files

[Jan Böcker]

On 23.03.2010 10:13, Leo Alekseyev wrote:
> Hi all,
> I am unable to open locally linked files if I use angle brackets to
> protect spaces, like so:
> 
>    [[<file:E:\ebooks\math\Probability and statistics\The Elements of
> Statistical Learning (2nd ed).pdf>][Hastie et al]]
> 
> -- the echo area displays "no such file: E:\ebooks\math\Probability
> and statistics\The Elements of Statistical Learning (2nd ed).pdf>"
> <---- note the right angle bracket here.  Generally, any file links
> with angle brackets refuse to open.  Is this a known bug?...  is there
> a patch?..  (Org mode 6.31a, emacs 23.1)

Hi Leo,

I could reproduce this, but I don't know if this is really a bug.
(I never heard of protecting spaces with angle brackets.)

You do not have to protect spaces, because the URL is surrounded by the
square brackets. I could only insert angle brackets into a link by
editing it manually; when you edit a link with C-c C-l and enclose the
URL in angle brackets, Org will automatically remove them.

HTH, Jan

Re: Problems with hyperlinked files

[Leo Alekseyev]

>
> I could reproduce this, but I don't know if this is really a bug.
> (I never heard of protecting spaces with angle brackets.)

Actually, it's right there in section 4.3 of the manual, last
sentence: "if you need to remove ambiguities about the end of the
link, enclose them in angular brackets. "

> You do not have to protect spaces, because the URL is surrounded by the
> square brackets. I could only insert angle brackets into a link by
> editing it manually; when you edit a link with C-c C-l and enclose the
> URL in angle brackets, Org will automatically remove them.

Thanks, both these methods work -- although I still think it would be
nice if org mode could properly handle angle brackets inside square
ones; the motivation here is that often I just paste in file paths
instead of  using C-c C-l, and then I have to use angle brackets to
deal w/ spaces; if I later want to change it to an annotated link, it
would be nice not to have to strip the angle brackets before wrapping
it in square ones...

Re: Problems with hyperlinked files

[Carsten Dominik]

On Mar 24, 2010, at 4:45 AM, Leo Alekseyev wrote:

>>
>> I could reproduce this, but I don't know if this is really a bug.
>> (I never heard of protecting spaces with angle brackets.)
>
> Actually, it's right there in section 4.3 of the manual, last
> sentence: "if you need to remove ambiguities about the end of the
> link, enclose them in angular brackets. "
>
>> You do not have to protect spaces, because the URL is surrounded by  
>> the
>> square brackets. I could only insert angle brackets into a link by
>> editing it manually; when you edit a link with C-c C-l and enclose  
>> the
>> URL in angle brackets, Org will automatically remove them.
>
> Thanks, both these methods work -- although I still think it would be
> nice if org mode could properly handle angle brackets inside square
> ones; the motivation here is that often I just paste in file paths
> instead of  using C-c C-l, and then I have to use angle brackets to
> deal w/ spaces; if I later want to change it to an annotated link, it
> would be nice not to have to strip the angle brackets before wrapping
> it in square ones...

It would be hard for Org to make that distinction in a stable way.  For
all it knows, the > might be part of the link.

Best habit is to always use [[..]] when you have a link
that contains spaces, just ignore the availability of
angular brackets as delimiters.  These were used historically
in Org before the bracket notation was introduced.

I am keeping that syntax for backward compatibility, but had
I had bracket links from the start, the angular bracket
representation would not exist today.

Best wishes

- Carsten

Re: Problems with hyperlinked files

[Jan Böcker]

On 24.03.2010 04:45, Leo Alekseyev wrote:

> Actually, it's right there in section 4.3 of the manual, last
> sentence: "if you need to remove ambiguities about the end of the
> link, enclose them in angular brackets. "
> 
Ah, I see -- this seems to be meant for the use case you mention below,
pasting in a URL without a description.

>> You do not have to protect spaces, because the URL is surrounded by the
>> square brackets. I could only insert angle brackets into a link by
>> editing it manually; when you edit a link with C-c C-l and enclose the
>> URL in angle brackets, Org will automatically remove them.
> 
> Thanks, both these methods work -- although I still think it would be
> nice if org mode could properly handle angle brackets inside square
> ones; the motivation here is that often I just paste in file paths
> instead of  using C-c C-l, and then I have to use angle brackets to
> deal w/ spaces; if I later want to change it to an annotated link, it
> would be nice not to have to strip the angle brackets before wrapping
> it in square ones...

Wouldn't you change it to an annotated link using C-c C-l anyway, which
would strip the square brackets for you? (C-c C-l can also edit existing
links, not only insert new ones.)


I looked at the code of org-open-at-point, and believe I can at least
explain the current behaviour (but I have no idea how a clean/elegant
fix would look):

- Org notices it is in a bracket link, say [[<file:~/s b.txt>]][test]]
- the link variable in org-open-at-point is set to "<file:~/s b.txt>"
- after expanding the ~ abbreviation, it is set to "<file:/home/jan/s b.txt"
- this string is not an absolute path, so it checks if
org-link-re-with-space3 matches, which is defined as follows:

"<?\\(http\\|https\\|ftp\\|mailto\\|file\\|news\\|shell\\|elisp\\|file\\+sys\\|file\\+emacs\\|bbdb\\|bibtex\\|docview\\|gnus\\|info\\|irc\\|mew\\|mhe\\|rmail\\|vm\\|wl\\|id\\):\\([^]

 <> ][^	
 ]*\\)"

Notice the optional < at the beginning? This regexp matches, and
captures "file" as the link type. Now Org takes the rest of the link,
"/home/jan/a b.txt>", and tries to open a non-existing file.


I assume angle brackets are not meant to be supported in bracket links,
because they are not needed there and are stripped by C-c C-l, but only
Carsten would know what the intended behaviour is here.


- Jan