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NAME

Markdown::Parser - Markdown Parser Only

SYNOPSIS

    use Markdown::Parser;
    my $p = Markdown::Parser->new;
    # Maybe with some callback?
    my $p = Markdown::Parser->new( callback => sub
    {
        my $obj = shift( @_ );
        # Do some processing with that Markdown object..
    });
    my $doc = $p->parse( $some_markdown_string ) || 
        die( $p->error );
    my $doc = $p->parse_file( $some_file ) ||
        die( $p->error );
    # Each element is an object inheriting from Markdown::Parser::Element
    printf( "%d children object collected.\n", $doc->children->length );
    my $markdown = $doc->as_markdown;
    my $html = $doc->as_string;
    my $pod = $doc->as_pod;

VERSION

    v0.3.2

DESCRIPTION

Markdown::Parser is an object oriented Markdown parser and manipulation interface.

It provides 2 modes: 1) strict and 2) extended

In strict mode, it conform rigorously to the Markdown specification as set out by its original author John Gruber and the extended mode, it accept and recognises extended Markdown syntax as set out in PHP Markdown Extra by Michel Fortin

CONSTRUCTOR

new

To instantiate a new Markdown::Parser object, pass an hash reference of following parameters:

abbreviation_case_sensitive

Boolean value to determine if abbreviation, that are extended markdown, should be case sensitive or not. Default is false, i.e. they are not case sensitive, so an abbreviation declaration like:

*[HTML4] Hypertext Markup Language Version 4

would match either HTML4 or html4 or even hTmL4

callback

Provided with a code reference, and this will register it as a callback to be triggered for every Markdown object encountered while parsing the data provided.

You can also provide undef

css_grid

A boolean value to set whether to return the tables as a css grid rather than as an html table.

This boolean value is passed to the "create_table" in Markdown::Parser::Element in the "parse_table" method.

CSS grids offer more flexibility and power than their conventional html counterparts.

To achieve this, this module uses CSS::Object and inserts necessary css rules to be added to an inline style in the head section of the html document.

Once the parsing is complete, you can get the CSS::Object object with "css" method.

debug

This is an integer. The bigger it is and the more verbose is the output.

mode

This can be either strict or extended. By default it is set to strict

EXCEPTION HANDLING

Whenever an error has occurred, Markdown::Parser will set a Module::Generic::Exception object containing the detail of the error and return undef.

The error object can be retrieved with the inherited "error" in Module::Generic method. For example:

    my $p = Markdown::Parser->new( debug => 3 ) || die( Markdown::Parser->error );

METHODS

abbreviation_case_sensitive

Boolean value that affects the way abbreviation are retrieved with "get_abbreviation" in Markdown::Parser::Document

callback

Sets or gets a code reference, and this will register it as a callback to be triggered for every Markdown object encountered while parsing the data provided.

You can also set undef to deactivate this feature.

charset

Sets or gets the character set for the document. Typically something like utf-8

code_highlight

Takes a boolean value.

This is currently unused.

create_document

Creates and returns a Markdown::Parser::Document object. This is a special object which is the top element.

css

Sets or get the CSS::Object objects. If one is set already, it is returned, or else an object is instantiated.

css_builder

This is a shortcut for the "builder" in CSS::Object method.

css_grid

A boolean value to set whether to return the tables as a css grid rather than as an html table.

default_email

Sets or gets the default email address to use, such as when setting up anti-spam measures.

See "as_string" in Markdown::Parser::Link

document

Contains the Markdown::Parser::Document object. An Markdown::Parser::Document object is created by "parser" to contain all the parsed markdown elements.

email_obfuscate_class

The css class to use when obfuscating email address.

See "as_string" in Markdown::Parser::Link

email_obfuscate_data_host

The fake host to use when performing email obfuscation.

See "as_string" in Markdown::Parser::Link

email_obfuscate_data_user

The fake user to use when performing email obfuscation.

See "as_string" in Markdown::Parser::Link

encrypt_email

Boolean value to mark e-mail address found to be encrypted. See Markdown::Parser::Link for more information.

footnote_ref_sequence

This is more an internal method used to keep track of the footnote reference found, i.e. something like:

    Here's a simple footnote,[^1] and here's a longer one.[^bignote]

So that the counter can be used to auto-generate number visible for those reference to footnotes.

This is differente from the footnote reference id i.e. the link from footnote back to the point where they are linked. For example:

    Here’s a simple footnote,1 and here’s a longer one.2

        1. This is the first footnote. ↩ # <-- Backlink is here

        2. Here’s one with multiple paragraphs and code. ↩ # <-- and here also

Here 1 and 2 are provided thanks to the "footnote_ref_sequence" and allocated to each Markdown::Parser::FootnoteReference

from_html

Provided with an HTML::Object::Element, presumably an HTML::Object::Document object, and this will do its best to import it as a Markdown::Parser::Document object.

It returns a Markdown::Parser::Document object upon success, and if an error occurred, it returns undef

katex_delimiter

Sets or gets an array reference.

The delimiter to use with katex

Returns an array object (Module::Generic::Array)

list_level

Sets or gets the list level. This takes an integer and is used during parsing of lists.

This method can be accessed as a regular method, or as a lvalue method, such as:

    $parser->list_level( 2 );
    # or
    $parser->list_level = 2;
    # or even
    $parser->list_level++;

mode

Sets or gets the mode for the parser. Possible value is strict or extended

If set to extended, the the scope of the parser will included non-standard markdown formattings.

parse

Provided with a string and some optional argument passed as an hash reference, and this will parse the string, create all the necessary object to represent the extent of the markdown document.

It returns the Markdown::Parser::Document object.

Possible arguments are:

element

A Markdown::Parser::Element subclass object that is used to store all newly created object from the parsing of the string provided.

"parse" is called recursively, so this makes it possible to set sub element as the container element in parsing.

scope

Can be a string or an array reference defining the extent of the scope within which the parser operates. For example, if it is set to strict, it will only parse standard markdown formatting and ignore the rest.

But, if we wanted to only parse paragraph and blockquotes and nothing else, its value would be:

    [qw( paragraph blockquote )]
scope_cond

Sets whether the scope item specified are to be understood as any one of them or all of them Thius possible value is any or all.

parse_file

Given a file path, and this will check if it can access the resource, and open the file and call "parse" on the content retrieved.

If for some reason, the file content could not be accessed, it returns undef and set an error using "error" in Module::Generic that this package inherits.

parse_list_item

This method is called when the parser encounters a markdown list.

It takes a string representing the entire list and an optional hash reference of options.

Possible options are:

doc

The Markdown::Parser::Element object to be used as container of all the item found during parsing.

pos

An integer representation the position at which the parsing should start.

It returns a Markdown::Parser::Document object.

parse_list_item

This method is called from within "parse" when an ordered or unordered list is found. It recursively parse the list data.

parse_table

This method is called from within "parse" when a table is found.

It will create a Markdown::Parser::Table and associated objects, such as Markdown::Parser::TableHeader, Markdown::Parser::TableBody and Markdown::Parser::Caption

There can be one to 2 lines of headers and multiple table bodies. Table headers and table bodies contain table rows, who, in turn, contain Markdown::Parser::TableCell objects.

parse_table_row

Provided with a string representing a table row, along with optional hash reference of options and this willparse the string and return an array reference of Markdown::Parser::TableRow objects. Each Markdown::Parser::TableRow object contains one or multiple instance of Markdown::Parser::TableCell objects.

scope

Returns the Markdown::Parser::Scope which is used during parsing to determine whether each element is part of the scope of not. During parsing, the scope may vary and may include only block element while sometime, the scope is limited to inline elements. For speed, the scope method "has" in Markdown::Parser::Scope is cached.

scope_block

Get a new scope parameter, in the form of an array reference, that has a scope for block elements.

scope_inline

Get a new scope parameter, in the form of an array reference, that has a scope for inline elements.

whereami

Provided with a scalar, an integer representing a position in the scalar, and an optional hash reference of options, and this method will print out or return a formatted string to visually show where exactly is the cursor in the string.

This is used solely for debugging and is resource intensive, so this along with the rest of the debugging method should not be used in live production.

This is activated when the parser object debug value is greater or equal to 3.

PRIVATE METHODS

_total_trailing_new_lines

Count how many trailing new lines there are in the given string and returns the number.

AUTHOR

Jacques Deguest <jack@deguest.jp>

SEE ALSO

Regexp::Common::Markdown for the regular expressions used in this distribution.

Text::Markdown::Discount for a fast markdown to html converter using C code.

Text::Markdown for a version in pure perl.

COPYRIGHT & LICENSE

Copyright (c) 2020 DEGUEST Pte. Ltd.

You can use, copy, modify and redistribute this package and associated files under the same terms as Perl itself.