/ 
BBCode-Parser-0.22
River stage zero No dependents
/ BBCode::Parser

NAME

BBCode::Parser - Parses BBCode tags

DESCRIPTION

BBCode is a simplified markup language used in several online forums and bulletin boards. It originated with phpBB, and remains most popular among applications written in PHP. Generally, users author their posts in BBCode, and the forum converts it to a permitted subset of well-formed HTML.

BBCode::Parser is a proper recursive parser for BBCode-formatted text.

OVERVIEW

A BBCode::Parser object represents various settings that affect the parsing process. Simple settings are typically set when the parser is created using "new", but they can be queried using "get" and altered using "set".

See "SETTINGS" for more information.

In addition to the simple settings, specific BBCode tags (or classes of tags) can be permitted or forbidden, using "permit" and "forbid" respectively. By default, the only forbidden tag is [HTML], which is normally a security violation if permitted.

See "CLASSES" for a list of tag classes.

Once the parser has been configured appropriately, parse trees can be created using the "parse" method. The parse tree will consist of objects derived from BBCode::Tag; the root of the tree will be a BBCode::Body.

Converting the parse tree to HTML is quite simple: call toHTML() on the root of the tree. Likewise, the parse tree can be converted back to BBCode by calling toBBCode(). See "METHODS" in BBCode::Tag to find out what other output methods are available.

SETTINGS

The following settings can be manipulated using "get" and "set".

css_prefix

(Type: String; Default: "bbcode-")

Many BBCode tags will add CSS classes as style hooks in the output HTML, such as <div class="bbcode-quote">...</div>. This setting allows you to override the naming scheme for those hooks. At the moment, more direct control of the CSS class names is not available.

css_direct_styles

(Type: Boolean; Default: FALSE)

Certain style-related BBCode tags, such as [U] (underline) and [S] (strike-through) don't have a direct equivalent in modern XHTML 1.0 Strict. If this value is TRUE, then the generated HTML will use a style attribute on a <span> tag to simulate the effects. If this value is FALSE, then the style attribute will be omitted. In either case, a class attribute is provided for use as a hook by external CSS stylesheets (not provided).

(Type: Boolean; Default: FALSE)

To prevent blog spam and the like, many search engines now allow HTML authors to indicate that specific URLs on a page should not be indexed. If this value is TRUE, then there will be nothing special about the URL (meaning that search engines are encouraged to follow the link). If this value is FALSE, then a rel="nofollow" attribute will be added wherever it makes sense (warning search engines that the link might be spam).

Whether or not to set this value to TRUE will depend on what you're using BBCode::Parser for. If you're implementing a forum or bulletin board, TRUE might be reserved for senior, more trusted members. If you're implementing a blog, the value might be TRUE for the blog owner but FALSE for visitors.

For more information, see http://www.google.com/webmasters/bot.html#www.

follow_override

(Type: Boolean; Default: FALSE)

This BBCode implementation allows a user to override the follow_links setting using a BBCode extension, FOLLOW=1. If this value is TRUE, the user can override follow_links; otherwise, the user must abide by follow_links.

The same considerations that apply to follow_links also apply to this setting.

allow_image_bullets

(Type: Boolean; Default: TRUE)

This setting allows you to restrict users from creating lists with custom bullets.

CLASSES

FIXME: Add documentation on tag classes.

METHODS

DEFAULT

my $tree = DEFAULT->parse($code);

DEFAULT returns the default parser. If you change the default parser, all future parsers created with "new" will incorporate your changes. However, all existing parsers will be unaffected.

clone

my $parser = BBCode::Parser->new(follow_links => 1);
my $clone = $parser->clone;
$clone->forbid('IMG');
printf "[IMG] is%s OK\n", ($parser->isPermitted('IMG') ? "" : " not");
# Prints "[IMG] is OK", since forbid('IMG') applies only to the clone.

clone creates a new parser that copies the settings of an existing parser. After cloning, the two parsers are completely independent; changing settings in one does not affect the other.

If any arguments are given, they are handed off to the set() method.

new

my $parser = BBCode::Parser->new(%args);

new creates a new BBCode::Parser. Any arguments are handed off to the set() method.

get

if($parser->get('follow_override')) {
	# [URL FOLLOW] permitted
} else {
	# [URL FOLLOW] forbidden
}

get fetches the current settings for the given parser. See "SETTINGS" for a list of available settings.

set

$parser->set(follow_override => 1);

set alters the settings for the given parser. See "SETTINGS" for a list of available settings.

permit

$parser->permit(qw(:INLINE !:LINK));

permit adds TAGs and :CLASSes to the list of permitted tags. Use '!' in front of a tag or class to negate the meaning.

forbid

$parser->forbid(qw(:ALL !:TEXT));

forbid adds TAGs and :CLASSes to the list of forbidden tags. Use '!' in front of a tag or class to negate the meaning.

isPermitted

if($parser->isPermitted('IMG')) {
	# Yay, [IMG] tags
} else {
	# Darn, no [IMG] tags
}

isPermitted checks if a tag is permitted by the current settings.

parse

my $tree = $parser->parse('[b]BBCode[/b] text.');

parse creates a parse tree for the given BBCode. The result is a tree of BBCode::Tag objects. The most common use of the parse tree is to convert it to HTML using BBCode::Tag->toHTML():

my $html = $tree->toHTML;

SEE ALSO

BBCode::Tag

svn://chronos-tachyon.net/projects/BBCode-Parser

AUTHOR

Donald King <dlking@cpan.org>