Find a library for parsing markdown files

[aoloe]

If possible something qt based.

[aoloe]

here are a few qt based markdown editors or otherwise markdown related projects:

• https://github.com/cloose/CuteMarkEd
• http://codeboje.de/markdown-editors/
• http://www.w3.org/community/markdown/wiki/MarkdownImplementations
• Stackoverflow: Markdown Implementations for C/C++
• https://github.com/sschober/qarkdown

[aoloe]

a -- simple -- sample parser implementation: http://www.qtcentre.org/threads/30707-Parse-Text-File-with-Qt

[aoloe]

an implementation in ocaml: https://github.com/MFP/OcsiBlog/blob/master/simple_markup.ml
(or https://github.com/mfp/ocsiblog/blob/more-markdown-compat/simple_markup.ml for more standard markdown)

a similar approach in php: https://github.com/erusev/parsedown/blob/master/Parsedown.php

and one in c: https://github.com/vmg/sundown/blob/master/src/markdown.c

[aoloe]

this is a good summary of the ways one can work on it:

http://stackoverflow.com/questions/605434/how-would-you-go-about-parsing-markdown

my conclusion is that it's probably best to split the file by line and then analyse each of them (or read the file one line at t time and then parse them)

[aoloe]

in the scribus code the about files look like markdown ones: http://scribus.net/svn/Scribus/trunk/Scribus/scribus/ui/about.cpp

[aoloe]

qlalr allows to parse a file based on a formal grammar (http://en.wikipedia.org/wiki/LALR_parser)

• it can be found here: https://qt.gitorious.org/qt/qlalr/
• it's not documented
• there are a few articles about it:
  • http://blog.qt.digia.com/blog/category/qlalr/
  • http://www.qtcentre.org/threads/34726-QLALR-examples
  • http://qt-project.org/quarterly/view/qlalr_adventures
• i've been looking for a formal grammar for markdown and i've found one for PEG: https://github.com/jgm/peg-markdown/blob/master/markdown_parser.leg. i could not find one for lalr.

the main idea is:

• you write a grammar
• run the grammar file through qlalr to generate c++ files
• include the generated .h files in your code
• extend the table class and get it to parse the files.

reading http://www.cforcoding.com/2010/01/markdown-and-introduction-to-parsing.html seems to show that markdown not being context free, it's hard to create a context free grammar for it.

[aoloe]

a peg parser may be a better idea:

• there is a syntax file for markdown: https://github.com/jgm/peg-markdown/blob/master/markdown_parser.leg
• there is a qt based genreator (https://code.google.com/p/qpeg/) but it's not maintained and in alpha stage
• there is a qt based markdown highlighter that uses the leg file from peg-markdown and the greg parser generator (also old and non maintained): https://github.com/vojto/peg-markdown-highlight