Re: [BUG] Trailing dash is not included in link [9.7.3 (9.7.3-2f1844 @ /home/mwillcock/.emacs.d/elpa/org-9.7.3/)]

[Ihor Radchenko <yantar92@posteo.net>]

Max Nikulin <manikulin@gmail.com> writes:

>> +*** Trailing =-= is now allowed in plain links
>
> After a look into
>
> 7dcb1afb6 2021-03-24 21:27:24 +0800 Ihor Radchenko: Improve 
> org-link-plain-re
>
> I suspect, it worked prior to v9.5. Without a unit test it may be 
> accidentally broken again.

No, it did not work.
If you can, please do not make such assertions without testing.

>> +: https://domain/test-
>
> example.org, example.net, example.com are domains reserved for usage in 
> examples: 
> <https://www.iana.org/assignments/special-use-domain-names/special-use-domain-names.xhtml>

And so?

>>                     (or (regexp "[^[:punct:] \t\n]")
>
> I have realized that some Org regexps use [:punct:] *regexp class* and 
> others *syntax class*, see latex math regexp. I am in doubts if the 
> discrepancy is intentional.

It is not intentional, but using syntax classes can sometimes be
fragile.

> I have noticed that the following change
>
> 09ced6d2c 2024-02-03 15:15:46 +0100 Ihor Radchenko: org-link-plain-re: 
> Improve regexp heuristics
>
> that causes
>
>      (link http://example.org/a<b)
>
> input is exported as
>
>      <p>
>      (link <a 
> href="http://example.org/a%3Cb)">http://example.org/a%3Cb)</a></p>
>
> I expect that ")" should not be parsed as a part of the link. Balanced 
> brackets are tricky with regexps (and it is not possible to match 
> arbitrary nested ones).

It is heuristics. We cannot be 100% right. So, it is what it is.

> Perhaps "[^[:punct:] \t\n]" is too strict in respect to spaces. It does 
> not allow the recommended workaround with zero width space:

You don't need zero width space for links.
Just use <bracket link>.

> As to the original bug report, while reading it, I noticed that 
> thunderbird includes dash into the recognized link for
>
>    "https://domain/test-"
>
> I decided to look into its implementation and to my surprise I found: 
> ``punctation chars and "-" at the end are stipped off.'' I realized that 
> double quotes along with angle brackets are treated as a recommended way 
> to mark URLs in plain text. Thunderbird does not consider dash as a part 
> of links for e.g. http://example.org/t- It might be an attempt to 
> reserve possibility to assemble URLs wrapped into several lines with 
> added hyphenation marks, but it has not been implemented (RFC2396 
> appendix E warns about accidentally added hyphens).
>
> https://www.bucksch.org/1/projects/mozilla/16507/
> https://searchfox.org/mozilla-central/source/netwerk/streamconv/converters/mozTXTToHTMLConv.cpp#line-243
> mozTXTToHTMLConv::FindURLEnd
>
> Implementation is tricky, I have not noticed anything that may be reused 
> to improve heuristics for Org. Nowadays it is likely better to inspect 
> autolinking code for GitHub/GitLab or widely used python packages.

If you have concrete proposals, please share them.

> I would consider [:space:] or \s-.

Do you mean "[^[:punct:][:space:]\t\n]"?

-- 
Ihor Radchenko // yantar92,
Org mode contributor,
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