NAME¶
Text::MediawikiFormat - Translate Wiki markup into other text formats
VERSION¶
Version 1.0
SYNOPSIS¶
use Text::MediawikiFormat 'wikiformat';
my $html = wikiformat ($raw);
my $text = wikiformat ($raw, {}, {implicit_links => 1});
DESCRIPTION¶
<
http://wikipedia.org> and its sister projects use the PHP Mediawiki to
format their pages. This module attempts to duplicate the Mediawiki formatting
rules. Those formatting rules can be simple and easy to use, while providing
more advanced options for the power user. They are also easy to translate into
other, more complicated markup languages with this module. It creates HTML by
default, but could produce valid POD, DocBook, XML, or any other format
imaginable.
The most important function is "Text::MediawikiFormat::format()". It
is not exported by default, but will be exported as "wikiformat()"
if any options at all are passed to the exporter, unless the name is
overridden explicitly. See "EXPORT" for more information.
It should be noted that this module is written as a drop in replacement for
Text::WikiMarkup that expands on that modules functionality and provides a
default rule set that may be used to format text like the PHP Mediawiki. It is
also well to note early that if you just want a Mediawiki clone (you don't
need to customize it heavily and you want integration with a back end
database), you should look at Wiki::Toolkit::Formatter::Mediawiki.
FUNCTIONS¶
"format()" takes one required argument, the text to convert, and
returns the converted text. It allows two optional arguments. The first is a
reference to a hash of tags used to override the function's default behavior.
Anything passed in here will override the default tags. The second argument is
a hash reference of options. The options are currently:
- prefix
- The prefix of any links to wiki pages. In HTML mode, this
is the path to the Wiki. The actual linked item itself will be appended to
the prefix. This is useful to create full URIs:
{prefix => 'http://example.com/wiki.pl?page='}
- extended
- A boolean flag, true by default, to let square brackets
mark links. An optional title may occur after the Wiki targets, preceded
by an open pipe. URI titles are separated from their title with a space.
These are valid extended links:
[[A wiki page|and the title to display]]
[http://ximbiot.com URI title]
Where the linking semantics of the destination format allow it, the result
will display the title instead of the URI. In HTML terms, the title is the
content of an "A" element (not the content of its
"HREF" attribute).
You can use delimiters other than single square brackets for marking
extended links by passing a value for "extended_link_delimiters"
in the %tags hash when calling "format".
Note that if you disable this flag, you should probably enable
"implicit_links" or there will be no automated way to link to
other pages in your wiki.
- implicit_links
- A boolean flag, false by default, to create links from
StudlyCapsStrings.
- absolute_links
- A boolean flag, true by default, which treats any links
that are absolute URIs (such as "http://www.cpan.org/")
specially. Any prefix will not apply. This should maybe be called
implicit_absolute_links since the "extended" option enables
absolute links inside square brackets by default.
A link is any text that starts with a known schema followed by a colon and
one or more non-whitespace characters. This is a distinct subset of what
URI recognizes as a URI, but is a good first-order approximation. If you
need to recognize more complex URIs, use the standard wiki formatting
explained earlier.
The recognized schemas are those defined in the "schema" value in
the %tags hash. "schema" defaults to "http",
"https", "ftp", "mailto", and
"gopher".
- process_html
- This flag, true by default, causes the formatter to ignore
block level wiki markup (code, ordered, unordered, etc...) when they occur
on lines which also contain allowed block-level HTML tags (<pre>,
<ol>, <ul>, </pre>, etc...). Phrase level wiki markup
(emphasis, strong, & links) is unaffected by this flag.
$formatted = format_line ($raw, $tags, $opts);
This function is never exported. It formats the phrase elements of a single line
of text (emphasised, strong, and links).
This is only meant to be called from Text::MediawikiFormat::Block and so
requires $tags and $opts to have all elements filled in. If you find a use for
it, please let me know and maybe I will have it default the missing elements
as "format()" does.
Refer to <
http://en.wikipedia.org/wiki/Help:Contents/Editing_Wikipedia>
for description of the default wiki format, as interpreted by this module. Any
discrepencies will be considered bugs in this module, with a few exceptions.
Unimplemented Wiki Markup¶
- Templates, Magic Words, and Wanted Links
- Templates, magic words, and the colorization of wanted
links all require a back end data store that can be consulted on the
existance and content of named pages. "Text::MediawikiFormat"
has deliberately been constructed such that it operates independantly from
such a back end. For an interface to "Text::MediawikiFormat"
which implements these features, see
Wiki::Toolkit::Formatter::Mediawiki.
- Tables
- This is on the TODO list.
EXPORT¶
If you'd like to make your life more convenient, you can optionally import a
subroutine that already has default tags and options set up. This is
especially handy if you use a prefix:
use Text::MediawikiFormat prefix => 'http://www.example.com/';
wikiformat ('some text');
Tags are interpreted as default members of the $tags hash normally passed to
"format", except for the five options (see above) and the
"as" key, who's value is interpreted as an alternate name for the
imported function.
To use the "as" flag to control the name by which your code calls the
imported function, for example,
use Text::MediawikiFormat as => 'formatTextWithWikiStyle';
formatTextWithWikiStyle ('some text');
You might choose a better name, though.
The calling semantics are effectively the same as those of the
"format()" function. Any additional tags or options to the imported
function will override the defaults. This code:
use Text::MediawikiFormat as => 'wf', extended => 0;
wf ('some text', {}, {extended => 1});
enables extended links, after specifying that the default behavior should be to
disable them.
GORY DETAILS¶
There are two types of Wiki markup: phrase markup and blocks. Blocks include
lists, which are made up of lines and can also contain other lists.
Phrase Markup
The are currently three types of wiki phrase markup. These are the strong and
emphasized markup and links. Links may additionally be of three subtypes,
extended, implicit, or absolute.
You can change the regular expressions used to find strong and emphasized tags:
%tags = (
strong_tag => qr/\*([^*]+?)\*/,
emphasized_tag => qr|/([^/]+?)/|,
);
$wikitext = 'this is *strong*, /emphasized/, and */em+strong/*';
$htmltext = wikiformat ($wikitext, \%tags, {});
You can also change the regular expressions used to find links. The following
just sets them to their default states (but enables parsing of implicit links,
which is
not the default):
my $html = wikiformat
(
$raw,
{implicit_link_delimiters => qr!\b(?:[A-Z][a-z0-9]\w*){2,}!,
extended_link_delimiters => qr!\[(?:\[[^][]*\]|[^][]*)\]!,
},
{implicit_links => 1}
);
In addition, you may set the function references that format strong and
emphasized text and links. The strong and emphasized functions receive only
the text to be formatted as an argument and are expected to return the
formatted text. The link formatter also recieves references to the $tags and
$opts arrays. For example, the following sets the strong and emphasized
formatters to their default state while replacing the link formatter with one
which strips href information and returns only the title text:
my $html = wikiformat
(
$raw,
{strong => sub {"<strong>$_[0]</strong>"},
emphasized => sub {"<em>$_[0]</em>"},
link => sub
{
my ($tag, $opts, $tags) = @_;
if ($tag =~ s/^\[\[([^][]+)\]\]$/$1/)
{
my ($page, $title) = split qr/\|/, $tag, 2;
return $title if $title;
return $page;
}
elsif ($tag =~ s/^\[([^][]+)\]$/$1/)
{
my ($href, $title) = split qr/ /, $tag, 2;
return $title if $title;
return $href;
}
else
{
return $tag;
}
},
},
);
Blocks
The default block types are "code", "line",
"paragraph", "paragraph_break", "unordered",
"ordered", "definition", and "header".
Block entries in the tag hashes must contain array references. The first two
items are the tags used at the start and end of the block. The third and
fourth contain the tags used at the start and end of each line. Where there
needs to be more processing of individual lines, use a subref as the third
item. This is how the module processes ordered lines in HTML lists and
headers:
my $html = wikiformat
(
$raw,
{ordered => ['<ol>', "</ol>\n", '<li>', "<li>\n"],
header => ['', "\n", \&_make_header],
},
);
The first argument to these subrefs is the post-processed text of the line
itself. (Processing removes the indentation and tokens used to mark this as a
list and checks the rest of the line for other line formattings.) The second
argument is the indentation level (see below). The subsequent arguments are
captured variables in the regular expression used to find this list type. The
regexp for headers is:
$html = wikiformat
(
$raw,
{blocks => {header => qr/^(=+)\s*(.+?)\s*\1$/}}
);
The module processes indentation first, if applicable, and stores the
indentation level (the length of the indentation removed).
Lists automatically start and end as necessary.
Because regular expressions could conceivably match more than one line, block
level markup is processed in a specific order. The "blockorder" tag
governs this order. It contains a reference to an array of the names of the
appropriate blocks to process. If you add a block type, be sure to add an
entry for it in "blockorder":
my $html = wikiformat
(
$raw,
{invisible => ['', '', '', ''],
blocks => {invisible => qr!^--(.*?)--$!},
blockorder => [qw(code header line ordered
unordered definition invisible
paragraph_break paragraph)]
},
},
);
Finding blocks
As has already been mentioned in passing, "Text::MediawikiFormat" uses
regular expressions to find blocks. These are in the %tags hash under the
"blocks" key. For example, to change the regular expression to find
code block items, use:
my $html = wikiformat ($raw, {blocks => {code => qr/^:\s+/}});
This will require a leading colon to mark code lines (note that as writted here,
this would interfere with the default processing of definition lists).
Finding Blocks in the Correct Order
As intrepid bug reporter Tom Hukins pointed out in CPAN RT bug #671, the order
in which "Text::MediawikiFormat" searches for blocks varies by
platform and version of Perl. Because some block-finding regular expressions
are more specific than others, what you intend to be one type of block may
turn into a different list type.
If you're adding new block types, be aware of this. The "blockorder"
entry in %tags exists to force "Text::MediawikiFormat" to apply its
regexes from most specific to least specific. It contains an array reference.
By default, it looks for ordered lists first, unordered lists second, and code
references at the end.
SEE ALSO¶
Wiki::Toolkit::Formatter::Mediawiki
SUPPORT¶
You can find documentation for this module with the perldoc command.
perldoc Text::MediawikiFormat
You can also look for information at:
- •
- AnnoCPAN: Annotated CPAN documentation
<http://annocpan.org/dist/Text-MediawikiFormat>
- •
- CPAN Ratings
<http://cpanratings.perl.org/d/Text-MediawikiFormat>
- •
- RT: CPAN's request tracker
<http://rt.cpan.org/NoAuth/Bugs.html?Dist=Text-MediawikiFormat>
- •
- Search CPAN
<http://search.cpan.org/dist/Text-MediawkiFormat>
AUTHOR¶
Derek Price "derek at ximbiot.com" is the author.
ACKNOWLEDGEMENTS¶
This module is derived from Text::WikiFormat, written by chromatic. chromatic's
original credits are below:
chromatic, "chromatic at wgz.org", with much input from the Jellybean
team (including Jonathan Paulett). Kate L Pugh has also provided several
patches, many failing tests, and is usually the driving force behind new
features and releases. If you think this module is worth buying me a beer, she
deserves at least half of it.
Alex Vandiver added a nice patch and tests for extended links.
Tony Bowden, Tom Hukins, and Andy H. all suggested useful features that are now
implemented.
Sam Vilain, Chris Winters, Paul Schmidt, and Art Henry have all found and
reported silly bugs.
Blame me for the implementation.
BUGS¶
The link checker in "format_line()" may fail to detect existing links
that do not follow HTML, XML, or SGML style. They may die with some SGML
styles too.
Sic transit gloria mundi.
TODO¶
- •
- Optimize "format_line()" to work on a list of
lines
COPYRIGHT & LICENSE¶
Copyright (c) 2006-2008 Derek R. Price, all rights reserved.
Copyright (c) 2002 - 2006, chromatic, all rights reserved.
This program is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.