## About ##

|            |                           |  
| ---------- | ------------------------- |  
| Title:     | libMultiMarkdown        |  
| Author:    | Fletcher T. Penney       |  
| Date:      | 2023-06-10 |  
| Copyright: | Copyright © 2016 - 2023 Fletcher T. Penney.    |  
| Version:   | 6.7.0      |  

master branch: [![Build Status](https://travis-ci.org/fletcher/MultiMarkdown-6.svg?branch=master)](https://travis-ci.org/fletcher/MultiMarkdown-6)  
develop branch: [![Build Status](https://travis-ci.org/fletcher/MultiMarkdown-6.svg?branch=develop)](https://travis-ci.org/fletcher/MultiMarkdown-6)

## An Announcement! ##

MultiMarkdown v6 is finally here!  If you want more information about
testing, see `DevelopmentNotes`.  

If you want to more know about the differences from v5, see the `QuickStart`
guide.


## Obtaining MultiMarkdown ##

You can download the latest installer for MacOS or Windows at Github:

<https://github.com/fletcher/MultiMarkdown-6/releases>

To build from source, download from Github.  Then:

	make release
	(OR)
	make debug

	cd build
	make

You can optionally test using the test suite:

	ctest


### Xcode

In order to use libMultiMarkdown in your Xcode project:

1.	`cd` into the root of your Xcode project folder (where the `.xcodeproj` file
	resides).

2.	Add this project as a git submodule:

		git submodule add https://github.com/fletcher/MultiMarkdown-6 MultiMarkdown-6

3.	Compile:

		cd MultiMarkdown-6
		make xcode

4.	Drag the `build-xcode/MultiMarkdown.xcodeproj` file to the root of your
	Xcode project as a subproject.

5.	Select the `MultiMarkdown` subproject, select the `libMultiMarkdown` target,
	and in Build Phases > Copy Files select Products Directory from the
	Destination popup menu.

6.	Select your root project, select your target, add `libMultiMarkdown` under
	Target Depencies and `libMultiMarkdown.framework/libMultiMarkdown` and
	`libcurl.tdb` under Link Binary with Libraries.

Warning: if you move the project on disk or update the MultiMarkdown source
files, you need to rerun step 3 above.

You can now `#import <libMultiMarkdown/libMultiMarkdown.h>`. To get you started,
here is (untested) demonstration code that converts a `NSString` to HTML:

	token_pool_init(); // needs to be done once per app lifecycle - PLEASE READ token.h!!!!!!!!!!!

	NSString *input = @"Test *string* for **demonstration**.";
	const char *cString = [input cStringUsingEncoding:NSUTF8StringEncoding];
	const char *mmd = mmd_string_convert(cString, EXT_SMART | EXT_NOTES | EXT_CRITIC | EXT_TRANSCLUDE, FORMAT_HTML, ENGLISH);
	NSString *output = [[NSString alloc] initWithCString:mmd encoding:NSUTF8StringEncoding];

	// Cleanup
	free(mmd); 
	token_pool_drain();		// again, PLEASE READ token.h!!!!!!
	token_pool_free();

There are 3 main versions of the primary functions:

* `mmd_string...`: start from source text in c string
* `mmd_d_string...`: start from a DString (Useful if you already use DString's for your text)
* `mmd_engine...`: useful when you are processing the same source multiple times

The C string variants are as follows:

	// Convert OPML string to MMD
	DString * mmd_string_convert_opml_to_text(const char * source);

	// Convert ITMZ string to MMD
	DString * mmd_string_convert_itmz_to_text(const char * source);

	// Convert MMD text to specified format, with specified extensions, and language
	// Returned char * must be freed
	char * mmd_string_convert(const char * source, unsigned long extensions, short format, short language);

	// Convert MMD text to specified format using DString as a container for block of data
	// and length of that block.  Must be used for "complex" output formats such as EPUB.
	// Returned DString * must be freed
	DString * mmd_string_convert_to_data(const char * source, unsigned long extensions, short format, short language, const char * directory);

	// Convert MMD text and write results to specified file -- used for "complex" output formats requiring
	// multiple documents (e.g. EPUB)
	void mmd_string_convert_to_file(const char * source, unsigned long extensions, short format, short language, const char * directory, const char * filepath);

	// Does the text have metadata?
	bool mmd_string_has_metadata(char * source, size_t * end);

	// Return metadata keys, one per line
	// Returned char * must be freed
	char * mmd_string_metadata_keys(char * source);

	// Extract desired metadata as string value
	// Returned char * must be freed
	char * mmd_string_metavalue_for_key(char * source, const char * key);

	// Insert/replace metadata in string, returning new string
	char * mmd_string_update_metavalue_for_key(const char * source, const char * key, const char * value);

	// Grab list of all transcluded files, but we need to know directory to search,
	// as well as the path to the file
	// Returned stack needs to be freed
	struct stack * mmd_string_transclusion_manifest(const char * source, const char * search_path, const char * source_path);

The following enums can be used for the parameters `language`, `format` and `extensions`:

	enum smart_quotes_language {
		ENGLISH = 0,
		DUTCH,
		FRENCH,
		GERMAN,
		GERMANGUILL,
		SPANISH,
		SWEDISH,
	};

	enum output_format {
		FORMAT_HTML,
		FORMAT_EPUB,
		FORMAT_LATEX,
		FORMAT_BEAMER,
		FORMAT_MEMOIR,
		FORMAT_FODT,
		FORMAT_ODT,
		FORMAT_TEXTBUNDLE,
		FORMAT_TEXTBUNDLE_COMPRESSED,
		FORMAT_OPML,
		FORMAT_ITMZ,
		FORMAT_MMD,
	};

	enum parser_extensions {
		EXT_COMPATIBILITY       = 1 << 0,    //!< Markdown compatibility mode
		EXT_COMPLETE            = 1 << 1,    //!< Create complete document
		EXT_SNIPPET             = 1 << 2,    //!< Create snippet only
		EXT_SMART               = 1 << 3,    //!< Enable Smart quotes
		EXT_NOTES               = 1 << 4,    //!< Enable Footnotes
		EXT_NO_LABELS           = 1 << 5,    //!< Don't add anchors to headers, etc.
		EXT_PROCESS_HTML        = 1 << 6,    //!< Process Markdown inside HTML
		EXT_NO_METADATA         = 1 << 7,    //!< Don't parse Metadata
		EXT_OBFUSCATE           = 1 << 8,    //!< Mask email addresses
		EXT_CRITIC              = 1 << 9,    //!< Critic Markup Support
		EXT_CRITIC_ACCEPT       = 1 << 10,   //!< Accept all proposed changes
		EXT_CRITIC_REJECT       = 1 << 11,   //!< Reject all proposed changes
		EXT_RANDOM_FOOT         = 1 << 12,   //!< Use random numbers for footnote links
		EXT_TRANSCLUDE          = 1 << 13,   //!< Perform transclusion(s)
		EXT_PARSE_OPML          = 1 << 14,   //!< Convert from OPML before processing source text
		EXT_PARSE_ITMZ			= 1 << 15,   //!< Convert from ITMZ (iThoughts) before processing source text
		EXT_RANDOM_LABELS		= 1 << 16,   //!< Use random numbers for header labels (unless manually defined)
		EXT_FAKE                = 1 << 31,   //!< 31 is highest number allowed
	};


## Differences in the MultiMarkdown Syntax ##

MultiMarkdown v6 is mostly about making a better MMD parser, but it involves a
few changes to the MultiMarkdown syntax itself.

1.	Setext headers can consist of more than one line to be included in the
header:

		This is
		a header
		========

2.	Whitespace is not allowed between the text brackets and label brackets in
reference links, images, footnotes, etc.  For example `[foo] [bar]` will no
longer be the same as `[foo][bar]`.

3.	Link and image titles can be quoted with `'foo'`, `"foo"`, or `(foo)`.
Link attributes can be used in both reference and inline links/images.

4.	HTML elements are handled slightly differently.  There is no longer a
`markdown="1"` feature.  Instead, HTML elements that are on a line by
themselves will open an HTML block that will cause the rest of the "paragraph"
to be treated as HTML such that Markdown will not be parsed in side of it.
HTML block-level tags are even "stronger" at starting an HTML block.  It is
not quite as complex as the approach used in CommonMark, but is similar under
most circumstances.  Leaving a blank line after the opening tag will allow
MultiMarkdown parsing inside of the HTML block.

	For example, this would not be parsed:

		<div>
		*foo*
		</div>

	But this would be:

		<div>

		*foo*

		</div>

5.	"Malformed" reference link definitions are handled slightly differently.
For example, the test suite file `Reference Footnotes.text` is parsed
differently in compatibility mode than MMD-5.  This started as a side-effect
of the parsing algorithm, but I actually think it makes sense.  This may or
may not change in the future.

6.	Table captions in MMD-6 must come immediately *after* the table, not
before it.

7.	Escaped linebreaks (`\` preceding a line break) will be interpreted as
`<br />` (even in compatibility mode).  This was previously an optional
feature in MMD, but I don't see a problem with just making it default 
behavior.

8.	Escaped spaces (`\ `) will be interpreted as a non-breaking space, if the
output format supports it.

9.	CriticMarkup, Abbreviations, Glossary Terms, and Citations are handled
slightly differently.  See the QuickStart guide for more information.

10.	Fenced code blocks can use leading/trailing "fences" of 3, 4, or 5
backticks in length.  That should be sufficient for complex documents without
requiring a more complex parser.  If there is no trailing fence, then the
fenced block is considered to go through the end of the document.

11.	Emph and Strong parsing is conceptually the same, but the implementation
is different.  It is designed for speed, accuracy, and consistency.  In
general, it seems to handle edge cases much more reliably, but there are still
a couple of situations that I would like to take into account, if possible.
These are not situations that should occur often in "real life."

12.	EPUB 3 output is supported without need of any external tools.

13.	Internationalization support for HTML phrases, such as "see footnote". See
[Github](https://github.com/fletcher/MultiMarkdown-6/issues/37) for more
information.



## License ##

	The `MultiMarkdown 6` project is released under the MIT License..
	
	GLibFacade.c and GLibFacade.h are from the MultiMarkdown v4 project:
	
		https://github.com/fletcher/MultiMarkdown-4/
	
	MMD 4 is released under both the MIT License and GPL.
	
	
	CuTest is released under the zlib/libpng license. See CuTest.c for the
	text of the license.
	
	uthash library:
		Copyright (c) 2005-2016, Troy D. Hanson
	
		Licensed under Revised BSD license
	
	miniz library:
		Copyright 2013-2014 RAD Game Tools and Valve Software
		Copyright 2010-2014 Rich Geldreich and Tenacious Software LLC
	
		Licensed under the MIT license
	
	argtable3 library:
		Copyright (C) 1998-2001,2003-2011,2013 Stewart Heitmann
		<sheitmann@users.sourceforge.net>
		All rights reserved.
	
		Licensed under the Revised BSD License
	
	
	## The MIT License ##
	
	Permission is hereby granted, free of charge, to any person obtaining
	a copy of this software and associated documentation files (the
	"Software"), to deal in the Software without restriction, including
	without limitation the rights to use, copy, modify, merge, publish,
	distribute, sublicense, and/or sell copies of the Software, and to
	permit persons to whom the Software is furnished to do so, subject to
	the following conditions:
	
	The above copyright notice and this permission notice shall be
	included in all copies or substantial portions of the Software.
	
	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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	CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
	SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	
	
	## Revised BSD License ##
	
	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions are
	met:
	    * Redistributions of source code must retain the above copyright
	      notice, this list of conditions and the following disclaimer.
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	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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