[Pkg-haskell-maintainers] Bug#687453: pandoc: Does not support spaces between () and [] for markdown-style hyperlinks

[John MacFarlane]

I believe you are misreading the syntax definition.
Here is the full context for the passage you quote:

> Reference-style links use a second set of square brackets, inside which
> you place a label of your choosing to identify the link:

>     This is [an example][id] reference-style link.
>
> You can optionally use a space to separate the sets of brackets:
>
>    This is [an example] [id] reference-style link.
>
> Then, anywhere in the document, you define your link label like this,
> on a line by itself:
>
>    [id]: http://example.com/ "Optional Title Here"

Note that this concerns only "reference-style links," which use
two sets of square brackets.  Links like this

    [foo](url)

are not reference-style link, but "inline links."  Here is what
the syntax document says about inline links:

> To create an inline link, use a set of regular parentheses immediately
> after the link text’s closing square bracket.

Note:  "immediately after," which is most naturally interpreted as
not allowing a space. This interpretation is confirmed by John Gruber's
reference implementation, Markdown.pl, which does not parse

    [foo] (url)

as a link, but does allow reference links like

    [foo] [bar]

So, to conclude, this does not seem to me to be a bug. Pandoc conforms
to the spec here and agrees with Markdown.pl.

Postscript: I myself think it would make more sense to allow a space in
both inline and reference links. I am just following the spec here. I
note that there is some variation among implementations on this point.
For example, PHP markdown agrees with Gruber's markdown, but my own
peg-markdown does allow the space.

+++ Axel Beckert [Sep 12 12 22:42 ]:
> Package: pandoc
> Version: 1.9.4.2-2
> Severity: minor
> 
> Dear Maintainer,
> 
> the Markdown hyperlink syntax definition explicitly states "You can
> optionally use a space to separate the sets of brackets", but pandoc's
> Markdown interpreter does not parse such hyperlink definitions.
> 
> Example: "[foo] (bar)" get's rendered as "[foo] (bar)" in HTML and
> man/roff output while "[foo](bar)" gets rendered properly as "foo (bar)"
> or '<a href="bar">foo</a>'.
> 
> The same problem arises if there's a line break between the two
> bracket pairs, e.g.
> 
> (foo)
> [bar]
> 
> (which is at least rendered as link by GitHub's Markdown parser, but not
> explicitly stated in the original definition.)
> 
> -- System Information:
> Debian Release: wheezy/sid
>   APT prefers unstable
>   APT policy: (990, 'unstable'), (600, 'testing'), (400, 'stable'), (110, 'experimental')
> Architecture: amd64 (x86_64)
> Foreign Architectures: i386
> 
> Kernel: Linux 3.5-trunk-amd64 (SMP w/1 CPU core)
> Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
> Shell: /bin/sh linked to /bin/dash
> 
> Versions of packages pandoc depends on:
> ii  libbibutils2  4.12-5
> ii  libc6         2.13-35
> ii  libffi5       3.0.10-3
> ii  libgmp10      2:5.0.5+dfsg-2
> ii  libpcre3      1:8.30-5
> ii  zlib1g        1:1.2.7.dfsg-13
> 
> Versions of packages pandoc recommends:
> pn  libghc-citeproc-hs-data  <none>
> 
> Versions of packages pandoc suggests:
> ii  texlive-latex-recommended  2012.20120611-4
> ii  texlive-luatex             2012.20120611-4
> ii  texlive-xetex              2012.20120611-4
> 
> -- no debconf information
>