Installation¶

Installation of libcmark

Please note that the libcmark API isn't stable yet. This version of the Perl bindings is known to work with all releases between 0.21.0 and 0.29.0, but there's no guarantee that it can be compiled with later versions. Also note that upgrading a dynamically linked version of libcmark may require recompilation of the Perl distribution.

It is recommended to use the libcmark packages provided by recent Linux distros. On Debian or Ubuntu, run:

    sudo apt-get install libcmark-dev

On Red Hat or CentOS, run:

    sudo yum install cmark-devel

To install libcmark from source:

    curl -LJO https://github.com/commonmark/cmark/archive/0.29.0.tar.gz
    tar xzf cmark-0.29.0.tar.gz
    cd cmark-0.29.0
    make [INSTALL_PREFIX=/prefix]
    make test
    make install

See the libcmark README for details.

Installation from a CPAN tarball

If libcmark is in a standard location:

    perl Makefile.PL
    make
    make test
    make install

Otherwise:

    perl Makefile.PL \
        INC="-I/prefix/include" \
        LIBS="-L/prefix/lib -lcmark"
    make
    make test
    make install

See the documentation of ExtUtils::MakeMaker for additional options. The PERL_MM_OPT environment variable is especially useful.

    export PERL_MM_OPT='INC="-I..." LIBS="-L... -lcmark"'

Build from a repository checkout

This distribution uses Dist::Zilla with the external plugins MakeMaker::Awesome and CopyFilesFromBuild. You can build and test with dzil:

    dzil test
    dzil build

The files generated by Dist::Zilla are included in the repository, so you can use the standard build process as well.

markdown_to_html¶

    my $html = CommonMark->markdown_to_html( $markdown, [$options] );

Converts a Markdown string to HTML. $options is a bit field containing the parser and render options. It defaults to zero ("OPT_DEFAULT").

Equivalent to

    my $html = CommonMark->parse_document($markdown)->render_html;

parse¶

    my $doc = CommonMark->parse(
        string        => $string,
        normalize     => $bool,    # Optional
        smart         => $bool,    # Optional
        validate_utf8 => $bool,    # Optional
    );
    my $doc = CommonMark->parse(
        file          => $handle,
        normalize     => $bool,    # Optional
        smart         => $bool,    # Optional
        validate_utf8 => $bool,    # Optional
    );

Convenience function to parse documents. Exactly one of the "string" or "file" options must be provided. When given a string, calls "parse_document". When given a file, calls "parse_file". "normalize", "smart", and "validate_utf8" enable the respective parser options.

Returns the CommonMark::Node of the root document.

parse_document¶

    my $doc = CommonMark->parse_document( $markdown, [$options] )

Parses a CommonMark document from a string returning the CommonMark::Node of the document root. $options is a bit field containing the parser options. It defaults to zero ("OPT_DEFAULT").

parse_file¶

    my $doc = CommonMark->parse_file( $file, [$options] );

Parses a CommonMark document from a file handle returning the CommonMark::Node of the document root. $options is a bit field containing the parser options. It defaults to zero ("OPT_DEFAULT").

Parser options¶

The parser options are a bit field created by ORing the following constants:

    CommonMark::OPT_DEFAULT => 0
    CommonMark::OPT_NORMALIZE
    CommonMark::OPT_VALIDATE_UTF8
    CommonMark::OPT_SMART

Parser options can be imported from CommonMark with tag "opt".

    use CommonMark qw(:opt);

"OPT_NORMALIZE" makes sure that adjacent text nodes are merged in the parse tree. This option has no effect with libcmark 0.28 or higher which always normalizes text nodes.

"OPT_SMART" enables the "smart quote" feature which turns vertical into typographic quotation marks, double and triple hyphens into en and em dashes, and triple periods into ellipses.

"OPT_VALIDATE_UTF8" turns on UTF-8 validation. Normally, this shouldn't be necessary because Perl strings should always contain valid UTF-8. But it is possible to create strings flagged as UTF-8 that contain invalid UTF-8, for example with XS. The option may be used if you don't trust the input data and want to make absolutely sure that the output is valid UTF-8. If invalid bytes are found, they are replaced with the Unicode replacement character U+FFFD.

Node creation¶

    my $document = CommonMark->create_document(
        children => \@children,
    );
    my $header = CommonMark->create_heading(
        level    => $level,
        children => \@children,
        text     => $literal,
    );
    my $paragraph = CommonMark->create_paragraph(
        children => \@children,
        text     => $literal,
    );
    my $block_quote = CommonMark->create_block_quote(
        children => \@children,
    );
    my $list = CommonMark->create_list(
        type     => $type,
        delim    => $delim,
        start    => $start,
        tight    => $tight,
        children => \@children,
    );
    my $item = CommonMark->create_item(
        children => \@children,
    );
    my $code_block = CommonMark->create_code_block(
        fence_info => $fence_info,
        literal    => $literal,
    );
    my $html = CommonMark->create_html_block(
        literal => $html,
    );
    my $custom_block = CommonMark->create_custom_block(
        on_enter => $raw_prefix,
        on_exit  => $raw_suffix,
        children => \@children,
        text     => $literal,
    );
    my $thematic_break = CommonMark->create_thematic_break;
    my $text = CommonMark->create_text(
        literal => $literal,
    );
    my $code = CommonMark->create_code(
        literal => $literal,
    );
    my $html_inline = CommonMark->create_html_inline(
        literal => $literal,
    );
    my $emph = CommonMark->create_emph(
        children => \@children,
        text     => $literal,
    );
    my $strong = CommonMark->create_strong(
        children => \@children,
        text     => $literal,
    );
    my $url = CommonMark->create_url(
        url      => $url,
        title    => $title,
        children => \@children,
        text     => $literal,
    );
    my $image = CommonMark->create_image(
        url      => $url,
        title    => $title,
        children => \@children,
        text     => $literal,
    );
    my $custom_inline = CommonMark->create_custom_inline(
        on_enter => $raw_prefix,
        on_exit  => $raw_suffix,
        children => \@children,
        text     => $literal,
    );
    my $softbreak = CommonMark->create_softbreak;
    my $linebreak = CommonMark->create_linebreak;

These convenience functions can be used to create nodes, set properties, and add children in a single operation. All parameters are optional.

The "children" parameter expects an arrayref of nodes to be added as children. The special "text" parameter adds a single text child with literal $literal. It can't be used together with "children". All other parameters correspond to a node property.

libcmark version information¶

    my $version = CommonMark->version;
    my $string  = CommonMark->version_string;
    my $version = CommonMark->compile_time_version;
    my $string  = CommonMark->compile_time_version_string;

Return the version number or version string of libcmark, either the library version linked against at run time or compile time.