NAME

Pandoc - wrapper for the mighty Pandoc document converter

SYNOPSIS

use Pandoc;             # check at first use
use Pandoc 1.12;        # check at compile time
Pandoc->require(1.12);  # check at run time

# execute pandoc
pandoc 'input.md', -o => 'output.html';
pandoc -f => 'html', -t => 'markdown', { in => \$html, out => \$md };

# alternative syntaxes
pandoc->run('input.md', -o => 'output.html');
pandoc [ -f => 'html', -t => 'markdown' ], in => \$html, out => \$md;
pandoc [ -f => 'html', -t => 'markdown' ], { in => \$html, out => \$md };

# check executable
pandoc or die "pandoc executable not found";

# check minimum version
pandoc->version > 1.12 or die "pandoc >= 1.12 required";

# access properties
say pandoc->bin." ".pandoc->version;
say "Default user data directory: ".pandoc->data_dir;
say "Compiled with: ".join(", ", keys %{ pandoc->libs });
say pandoc->libs->{'highlighting-kate'};

# create a new instance with default arguments
my $md2latex = Pandoc->new(qw(-f markdown -t latex --number-sections));
$md2latex->run({ in => \$markdown, out => \$latex });

# create a new instance with selected executable
my $pandoc = Pandoc->new('bin/pandoc');
my $pandoc = Pandoc->new('2.1'); # use ~/.pandoc/bin/pandoc-2.1 if available

# set default arguments on compile time
use Pandoc qw(-t latex);
use Pandoc qw(/usr/bin/pandoc --number-sections);
use Pandoc qw(1.16 --number-sections);

# utility method to convert from string
$latex = pandoc->convert( 'markdown' => 'latex', '*hello*' );

# utility methods to parse abstract syntax tree (requires Pandoc::Elements)
$doc = pandoc->parse( markdown => '*hello* **world!**' );
$doc = pandoc->file( 'example.md' );
$doc = pandoc->file;  # read Markdown from STDIN

DESCRIPTION

This module provides a Perl wrapper for John MacFarlane's Pandoc document converter.

INSTALLATION

This module requires the Perl programming language (>= version 5.14) as included in most Unix operating systems by default. The recommended method to install Perl modules is cpanm (see its install instructions if needed):

cpanm Pandoc

Installing instruction for Pandoc itself are given at Pandoc homepage. On Debian-based systems this module and script pandoc-version can be used to install and update the pandoc executable with Pandoc::Release:

pandoc-version install

Then add ~/.pandoc/bin to your PATH or copy ~/.pandoc/bin/pandoc to a location where it can be executed.

USAGE

The utility function pandoc is exported, unless the module is imported with an empty list (use Pandoc ();). Importing this module with a version number or a more complex version requirenment (e.g. use Pandoc 1.13; or use Pandoc '>= 1.6, !=1.7) will check version number of pandoc executable instead of version number of this module (see $Pandoc::VERSION for the latter). Additional import arguments can be passed to set the executable location and default arguments of the global Pandoc instance used by function pandoc.

FUNCTIONS

pandoc

If called without parameters, this function returns a global instance of class Pandoc to execute methods, or undef if no pandoc executable was found. The location and/or name of pandoc executable can be set with environment variable PANDOC_PATH (set to the string pandoc by default).

pandoc( ... )

If called with parameters, this functions runs the pandoc executable configured at the global instance of class Pandoc (pandoc->bin). Arguments (given as array or array reference) are passed as pandoc command line arguments. Additional options (given as hash or has reference) can control input, output, and error stream:

pandoc @arguments, \%options;     # ok
pandoc \@arguments, %options;     # ok
pandoc \@arguments, \%options;    # ok
pandoc @arguments;                # ok, if first of @arguments starts with '-'
pandoc %options;                  # ok, if %options is not empty

pandoc @arguments, %options;      # not ok!

Returns 0 on success. On error returns the exit code of pandoc executable or -1 if execution failed. If option throw is set, a Pandoc::Error is thrown instead. The following options are recognized:

in / out / err

These options correspond to arguments $stdin, $stdout, and $stderr of IPC::Run3, see there for details.

binmode_stdin / binmode_stdout / binmode_stderr

These options correspond to the like-named options to IPC::Run3, see there for details.

binmode

If defined any binmode_stdin/binmode_stdout/binmode_stderr option which is undefined will be set to this value.

throw

Throw a Pandoc::Error instead returning the exit code on error. Disabled by default.

return_if_system_error

Set to negation of option throw by default.

For convenience the pandoc function (after checking the binmode option) checks the contents of any scalar references passed to the in/out/err options with utf8::is_utf8() and sets the binmode_stdin/binmode_stdout/binmode_stderr options to :encoding(UTF-8) if the corresponding scalar is marked as UTF-8 and the respective option is undefined. Since all pandoc executable input/output must be UTF-8 encoded this is convenient if you run with use utf8, as you then don't need to set the binmode options at all (encode nor decode) when passing input/output scalar references.

pandoc_data_dir( [ @subdirs ] [ $file ] )

Returns the default pandoc data directory which is directory .pandoc in the home directory for Unix or pandoc directory in %APPDATA% for Windows. Optional arguments can be given to refer to a specific subdirectory or file.

METHODS

new( [ $executable | $version ] [, @arguments ] )

Create a new instance of class Pandoc or throw an exception if no pandoc executable was found. The first argument, if given and not starting with -, can be used to set the pandoc executable (pandoc by default). If a version is specified the executable is also searched in ~/.pandoc/bin, e.g. ~/.pandoc/bin/pandoc-2.0 for version 2.0. Additional arguments are passed to the executable on each run.

Repeated use of this constructor with same arguments is not recommended because pandoc --version is called for every new instance.

run( ... )

Execute the pandoc executable with default arguments and optional additional arguments and options. See function pandoc for usage.

convert( $from => $to, $input [, @arguments ] )

Convert a string in format $from to format $to. Additional pandoc options such as -N and --standalone can be passed. The result is returned in same utf8 mode (utf8::is_unicode) as the input. To convert from file to string use method pandoc/run like this and set input/output format via standard pandoc arguments -f and -t:

pandoc->run( $filename, @arguments, { out => \$string } );

parse( $from => $input [, @arguments ] )

Parse a string in format $from to a Pandoc::Document object. Additional pandoc options such as -N and --normalize can be passed. This method requires at least pandoc version 1.12.1 and the Perl module Pandoc::Elements.

The reverse action is possible with method to_pandoc of Pandoc::Document. Additional shortcut methods such as to_html are available:

$html = pandoc->parse( 'markdown' => '# A *section*' )->to_html;

Method convert should be preferred for simple conversions unless you want to modify or inspect the parsed document in between.

file( [ $filename [, @arguments ] ] )

Parse from a file (or STDIN) to a Pandoc::Document object. Additional pandoc options can be passed, for instance use HTML input format (@arguments = qw(-f html)) instead of default markdown. This method requires at least pandoc version 1.12.1 and the Perl module Pandoc::Elements.

require( $version_requirement )

Return the Pandoc instance if its version number fulfills a given version requirement. Throw an error otherwise. Can also be called as constructor: Pandoc->require(...) is equivalent to pandoc->require but throws a more meaningful error message if no pandoc executable was found.

version( [ $version_requirement ] )

Return the pandoc version as Pandoc::Version object. If a version requirement is given, the method returns undef if the pandoc version does not fulfill this requirement. To check whether pandoc is available with a given minimal version use one of:

Pandoc->require( $minimum_version)                # true or die
pandoc and pandoc->version( $minimum_version )    # true or false

bin( [ $executable ] )

Return or set the pandoc executable. Setting an new executable also updates version and data_dir by calling pandoc --version.

symlink( [ $name ] [ verbose => 0|1 ] )

Create a symlink with given name to the executable and change executable to the symlink location afterwards. An existing symlink is replaced. If $name is an existing directory, the symlink will be named pandoc in there. This makes most sense if the directory is listed in environment variable $PATH. If the name is omitted or an empty string, symlink is created in subdirectory bin of pandoc data directory.

arguments( [ @arguments | \@arguments )

Return or set a list of default arguments.

data_dir( [ @subdirs ] [ $file ] )

Return the stated default data directory, introduced with Pandoc 1.11. Use function pandoc_data_dir alternatively to get the expected directory without calling Pandoc executable.

input_formats

Return a list of supported input formats.

output_formats

Return a list of supported output formats.

highlight_languages

Return a list of programming languages which syntax highlighting is supported for (via Haskell library highlighting-kate).

extensions( [ $format ] )

Return a hash of extensions mapped to whether they are enabled by default. This method is only available since Pandoc 1.18 and the optional format argument since Pandoc 2.0.6.

libs

Return a hash mapping the names of Haskell libraries compiled into the pandoc executable to Pandoc::Version objects.

SEE ALSO

This package includes Pandoc::Version to compare Pandoc version numbers, Pandoc::Release to get Pandoc releases from GitHub, and App::Prove::Plugin::andoc to run tests with selected Pandoc executables.

See Pandoc::Elements for a Perl interface to the abstract syntax tree of Pandoc documents for more elaborate document processing.

See Pod::Pandoc to parse Plain Old Documentation format (perlpod) for processing with Pandoc.

See Pandoc wrappers and interfaces in the Pandoc GitHub Wiki for a list of wrappers in other programming languages.

Other Pandoc related but outdated modules at CPAN include Orze::Sources::Pandoc and App::PDoc.

AUTHOR

Jakob Voß

CONTRIBUTORS

Benct Philip Jonsson

LICENSE

European Union Public Licence v. 1.2 (EUPL-1.2)