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authorJason A. Donenfeld <Jason@zx2c4.com>2013-05-27 19:39:43 +0000
committerJason A. Donenfeld <Jason@zx2c4.com>2013-05-27 19:54:16 +0000
commit8149be213f1c8f52b0dbe6c213f6073af57fa954 (patch)
treee4d0315f53022bb7335f782ad394d8e7602f1b52 /filters/html-converters/resources/markdown.pl
parentdcbc0438b2543a733858d62170f3110a89edbed6 (diff)
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filters: import more modern scripts
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Diffstat (limited to 'filters/html-converters/resources/markdown.pl')
-rwxr-xr-xfilters/html-converters/resources/markdown.pl1731
1 files changed, 1731 insertions, 0 deletions
diff --git a/filters/html-converters/resources/markdown.pl b/filters/html-converters/resources/markdown.pl
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+#!/usr/bin/perl
+
+#
+# Markdown -- A text-to-HTML conversion tool for web writers
+#
+# Copyright (c) 2004 John Gruber
+# <http://daringfireball.net/projects/markdown/>
+#
+
+
+package Markdown;
+require 5.006_000;
+use strict;
+use warnings;
+
+use Digest::MD5 qw(md5_hex);
+use vars qw($VERSION);
+$VERSION = '1.0.1';
+# Tue 14 Dec 2004
+
+## Disabled; causes problems under Perl 5.6.1:
+use utf8;
+binmode( STDOUT, ":utf8" ); # c.f.: http://acis.openlib.org/dev/perl-unicode-struggle.html
+
+
+#
+# Global default settings:
+#
+my $g_empty_element_suffix = " />"; # Change to ">" for HTML output
+my $g_tab_width = 4;
+
+
+#
+# Globals:
+#
+
+# Regex to match balanced [brackets]. See Friedl's
+# "Mastering Regular Expressions", 2nd Ed., pp. 328-331.
+my $g_nested_brackets;
+$g_nested_brackets = qr{
+ (?> # Atomic matching
+ [^\[\]]+ # Anything other than brackets
+ |
+ \[
+ (??{ $g_nested_brackets }) # Recursive set of nested brackets
+ \]
+ )*
+}x;
+
+
+# Table of hash values for escaped characters:
+my %g_escape_table;
+foreach my $char (split //, '\\`*_{}[]()>#+-.!') {
+ $g_escape_table{$char} = md5_hex($char);
+}
+
+
+# Global hashes, used by various utility routines
+my %g_urls;
+my %g_titles;
+my %g_html_blocks;
+
+# Used to track when we're inside an ordered or unordered list
+# (see _ProcessListItems() for details):
+my $g_list_level = 0;
+
+
+#### Blosxom plug-in interface ##########################################
+
+# Set $g_blosxom_use_meta to 1 to use Blosxom's meta plug-in to determine
+# which posts Markdown should process, using a "meta-markup: markdown"
+# header. If it's set to 0 (the default), Markdown will process all
+# entries.
+my $g_blosxom_use_meta = 0;
+
+sub start { 1; }
+sub story {
+ my($pkg, $path, $filename, $story_ref, $title_ref, $body_ref) = @_;
+
+ if ( (! $g_blosxom_use_meta) or
+ (defined($meta::markup) and ($meta::markup =~ /^\s*markdown\s*$/i))
+ ){
+ $$body_ref = Markdown($$body_ref);
+ }
+ 1;
+}
+
+
+#### Movable Type plug-in interface #####################################
+eval {require MT}; # Test to see if we're running in MT.
+unless ($@) {
+ require MT;
+ import MT;
+ require MT::Template::Context;
+ import MT::Template::Context;
+
+ eval {require MT::Plugin}; # Test to see if we're running >= MT 3.0.
+ unless ($@) {
+ require MT::Plugin;
+ import MT::Plugin;
+ my $plugin = new MT::Plugin({
+ name => "Markdown",
+ description => "A plain-text-to-HTML formatting plugin. (Version: $VERSION)",
+ doc_link => 'http://daringfireball.net/projects/markdown/'
+ });
+ MT->add_plugin( $plugin );
+ }
+
+ MT::Template::Context->add_container_tag(MarkdownOptions => sub {
+ my $ctx = shift;
+ my $args = shift;
+ my $builder = $ctx->stash('builder');
+ my $tokens = $ctx->stash('tokens');
+
+ if (defined ($args->{'output'}) ) {
+ $ctx->stash('markdown_output', lc $args->{'output'});
+ }
+
+ defined (my $str = $builder->build($ctx, $tokens) )
+ or return $ctx->error($builder->errstr);
+ $str; # return value
+ });
+
+ MT->add_text_filter('markdown' => {
+ label => 'Markdown',
+ docs => 'http://daringfireball.net/projects/markdown/',
+ on_format => sub {
+ my $text = shift;
+ my $ctx = shift;
+ my $raw = 0;
+ if (defined $ctx) {
+ my $output = $ctx->stash('markdown_output');
+ if (defined $output && $output =~ m/^html/i) {
+ $g_empty_element_suffix = ">";
+ $ctx->stash('markdown_output', '');
+ }
+ elsif (defined $output && $output eq 'raw') {
+ $raw = 1;
+ $ctx->stash('markdown_output', '');
+ }
+ else {
+ $raw = 0;
+ $g_empty_element_suffix = " />";
+ }
+ }
+ $text = $raw ? $text : Markdown($text);
+ $text;
+ },
+ });
+
+ # If SmartyPants is loaded, add a combo Markdown/SmartyPants text filter:
+ my $smartypants;
+
+ {
+ no warnings "once";
+ $smartypants = $MT::Template::Context::Global_filters{'smarty_pants'};
+ }
+
+ if ($smartypants) {
+ MT->add_text_filter('markdown_with_smartypants' => {
+ label => 'Markdown With SmartyPants',
+ docs => 'http://daringfireball.net/projects/markdown/',
+ on_format => sub {
+ my $text = shift;
+ my $ctx = shift;
+ if (defined $ctx) {
+ my $output = $ctx->stash('markdown_output');
+ if (defined $output && $output eq 'html') {
+ $g_empty_element_suffix = ">";
+ }
+ else {
+ $g_empty_element_suffix = " />";
+ }
+ }
+ $text = Markdown($text);
+ $text = $smartypants->($text, '1');
+ },
+ });
+ }
+}
+else {
+#### BBEdit/command-line text filter interface ##########################
+# Needs to be hidden from MT (and Blosxom when running in static mode).
+
+ # We're only using $blosxom::version once; tell Perl not to warn us:
+ no warnings 'once';
+ unless ( defined($blosxom::version) ) {
+ use warnings;
+
+ #### Check for command-line switches: #################
+ my %cli_opts;
+ use Getopt::Long;
+ Getopt::Long::Configure('pass_through');
+ GetOptions(\%cli_opts,
+ 'version',
+ 'shortversion',
+ 'html4tags',
+ );
+ if ($cli_opts{'version'}) { # Version info
+ print "\nThis is Markdown, version $VERSION.\n";
+ print "Copyright 2004 John Gruber\n";
+ print "http://daringfireball.net/projects/markdown/\n\n";
+ exit 0;
+ }
+ if ($cli_opts{'shortversion'}) { # Just the version number string.
+ print $VERSION;
+ exit 0;
+ }
+ if ($cli_opts{'html4tags'}) { # Use HTML tag style instead of XHTML
+ $g_empty_element_suffix = ">";
+ }
+
+
+ #### Process incoming text: ###########################
+ my $text;
+ {
+ local $/; # Slurp the whole file
+ $text = <>;
+ }
+ print <<'EOT';
+<style>
+.markdown-body {
+ font-size: 14px;
+ line-height: 1.6;
+ overflow: hidden;
+}
+.markdown-body>*:first-child {
+ margin-top: 0 !important;
+}
+.markdown-body>*:last-child {
+ margin-bottom: 0 !important;
+}
+.markdown-body a.absent {
+ color: #c00;
+}
+.markdown-body a.anchor {
+ display: block;
+ padding-left: 30px;
+ margin-left: -30px;
+ cursor: pointer;
+ position: absolute;
+ top: 0;
+ left: 0;
+ bottom: 0;
+}
+.markdown-body h1, .markdown-body h2, .markdown-body h3, .markdown-body h4, .markdown-body h5, .markdown-body h6 {
+ margin: 20px 0 10px;
+ padding: 0;
+ font-weight: bold;
+ -webkit-font-smoothing: antialiased;
+ cursor: text;
+ position: relative;
+}
+.markdown-body h1 .mini-icon-link, .markdown-body h2 .mini-icon-link, .markdown-body h3 .mini-icon-link, .markdown-body h4 .mini-icon-link, .markdown-body h5 .mini-icon-link, .markdown-body h6 .mini-icon-link {
+ display: none;
+ color: #000;
+}
+.markdown-body h1:hover a.anchor, .markdown-body h2:hover a.anchor, .markdown-body h3:hover a.anchor, .markdown-body h4:hover a.anchor, .markdown-body h5:hover a.anchor, .markdown-body h6:hover a.anchor {
+ text-decoration: none;
+ line-height: 1;
+ padding-left: 0;
+ margin-left: -22px;
+ top: 15%}
+.markdown-body h1:hover a.anchor .mini-icon-link, .markdown-body h2:hover a.anchor .mini-icon-link, .markdown-body h3:hover a.anchor .mini-icon-link, .markdown-body h4:hover a.anchor .mini-icon-link, .markdown-body h5:hover a.anchor .mini-icon-link, .markdown-body h6:hover a.anchor .mini-icon-link {
+ display: inline-block;
+}
+.markdown-body h1 tt, .markdown-body h1 code, .markdown-body h2 tt, .markdown-body h2 code, .markdown-body h3 tt, .markdown-body h3 code, .markdown-body h4 tt, .markdown-body h4 code, .markdown-body h5 tt, .markdown-body h5 code, .markdown-body h6 tt, .markdown-body h6 code {
+ font-size: inherit;
+}
+.markdown-body h1 {
+ font-size: 28px;
+ color: #000;
+}
+.markdown-body h2 {
+ font-size: 24px;
+ border-bottom: 1px solid #ccc;
+ color: #000;
+}
+.markdown-body h3 {
+ font-size: 18px;
+}
+.markdown-body h4 {
+ font-size: 16px;
+}
+.markdown-body h5 {
+ font-size: 14px;
+}
+.markdown-body h6 {
+ color: #777;
+ font-size: 14px;
+}
+.markdown-body p, .markdown-body blockquote, .markdown-body ul, .markdown-body ol, .markdown-body dl, .markdown-body table, .markdown-body pre {
+ margin: 15px 0;
+}
+.markdown-body hr {
+ background: transparent url("/dirty-shade.png") repeat-x 0 0;
+ border: 0 none;
+ color: #ccc;
+ height: 4px;
+ padding: 0;
+}
+.markdown-body>h2:first-child, .markdown-body>h1:first-child, .markdown-body>h1:first-child+h2, .markdown-body>h3:first-child, .markdown-body>h4:first-child, .markdown-body>h5:first-child, .markdown-body>h6:first-child {
+ margin-top: 0;
+ padding-top: 0;
+}
+.markdown-body a:first-child h1, .markdown-body a:first-child h2, .markdown-body a:first-child h3, .markdown-body a:first-child h4, .markdown-body a:first-child h5, .markdown-body a:first-child h6 {
+ margin-top: 0;
+ padding-top: 0;
+}
+.markdown-body h1+p, .markdown-body h2+p, .markdown-body h3+p, .markdown-body h4+p, .markdown-body h5+p, .markdown-body h6+p {
+ margin-top: 0;
+}
+.markdown-body li p.first {
+ display: inline-block;
+}
+.markdown-body ul, .markdown-body ol {
+ padding-left: 30px;
+}
+.markdown-body ul.no-list, .markdown-body ol.no-list {
+ list-style-type: none;
+ padding: 0;
+}
+.markdown-body ul li>:first-child, .markdown-body ul li ul:first-of-type, .markdown-body ul li ol:first-of-type, .markdown-body ol li>:first-child, .markdown-body ol li ul:first-of-type, .markdown-body ol li ol:first-of-type {
+ margin-top: 0px;
+}
+.markdown-body ul li p:last-of-type, .markdown-body ol li p:last-of-type {
+ margin-bottom: 0;
+}
+.markdown-body ul ul, .markdown-body ul ol, .markdown-body ol ol, .markdown-body ol ul {
+ margin-bottom: 0;
+}
+.markdown-body dl {
+ padding: 0;
+}
+.markdown-body dl dt {
+ font-size: 14px;
+ font-weight: bold;
+ font-style: italic;
+ padding: 0;
+ margin: 15px 0 5px;
+}
+.markdown-body dl dt:first-child {
+ padding: 0;
+}
+.markdown-body dl dt>:first-child {
+ margin-top: 0px;
+}
+.markdown-body dl dt>:last-child {
+ margin-bottom: 0px;
+}
+.markdown-body dl dd {
+ margin: 0 0 15px;
+ padding: 0 15px;
+}
+.markdown-body dl dd>:first-child {
+ margin-top: 0px;
+}
+.markdown-body dl dd>:last-child {
+ margin-bottom: 0px;
+}
+.markdown-body blockquote {
+ border-left: 4px solid #DDD;
+ padding: 0 15px;
+ color: #777;
+}
+.markdown-body blockquote>:first-child {
+ margin-top: 0px;
+}
+.markdown-body blockquote>:last-child {
+ margin-bottom: 0px;
+}
+.markdown-body table th {
+ font-weight: bold;
+}
+.markdown-body table th, .markdown-body table td {
+ border: 1px solid #ccc;
+ padding: 6px 13px;
+}
+.markdown-body table tr {
+ border-top: 1px solid #ccc;
+ background-color: #fff;
+}
+.markdown-body table tr:nth-child(2n) {
+ background-color: #f8f8f8;
+}
+.markdown-body img {
+ max-width: 100%;
+ -moz-box-sizing: border-box;
+ box-sizing: border-box;
+}
+.markdown-body span.frame {
+ display: block;
+ overflow: hidden;
+}
+.markdown-body span.frame>span {
+ border: 1px solid #ddd;
+ display: block;
+ float: left;
+ overflow: hidden;
+ margin: 13px 0 0;
+ padding: 7px;
+ width: auto;
+}
+.markdown-body span.frame span img {
+ display: block;
+ float: left;
+}
+.markdown-body span.frame span span {
+ clear: both;
+ color: #333;
+ display: block;
+ padding: 5px 0 0;
+}
+.markdown-body span.align-center {
+ display: block;
+ overflow: hidden;
+ clear: both;
+}
+.markdown-body span.align-center>span {
+ display: block;
+ overflow: hidden;
+ margin: 13px auto 0;
+ text-align: center;
+}
+.markdown-body span.align-center span img {
+ margin: 0 auto;
+ text-align: center;
+}
+.markdown-body span.align-right {
+ display: block;
+ overflow: hidden;
+ clear: both;
+}
+.markdown-body span.align-right>span {
+ display: block;
+ overflow: hidden;
+ margin: 13px 0 0;
+ text-align: right;
+}
+.markdown-body span.align-right span img {
+ margin: 0;
+ text-align: right;
+}
+.markdown-body span.float-left {
+ display: block;
+ margin-right: 13px;
+ overflow: hidden;
+ float: left;
+}
+.markdown-body span.float-left span {
+ margin: 13px 0 0;
+}
+.markdown-body span.float-right {
+ display: block;
+ margin-left: 13px;
+ overflow: hidden;
+ float: right;
+}
+.markdown-body span.float-right>span {
+ display: block;
+ overflow: hidden;
+ margin: 13px auto 0;
+ text-align: right;
+}
+.markdown-body code, .markdown-body tt {
+ margin: 0 2px;
+ padding: 0px 5px;
+ border: 1px solid #eaeaea;
+ background-color: #f8f8f8;
+ border-radius: 3px;
+}
+.markdown-body code {
+ white-space: nowrap;
+}
+.markdown-body pre>code {
+ margin: 0;
+ padding: 0;
+ white-space: pre;
+ border: none;
+ background: transparent;
+}
+.markdown-body .highlight pre, .markdown-body pre {
+ background-color: #f8f8f8;
+ border: 1px solid #ccc;
+ font-size: 13px;
+ line-height: 19px;
+ overflow: auto;
+ padding: 6px 10px;
+ border-radius: 3px;
+}
+.markdown-body pre code, .markdown-body pre tt {
+ margin: 0;
+ padding: 0;
+ background-color: transparent;
+ border: none;
+}
+</style>
+EOT
+ print "<div class='markdown-body'>";
+ print Markdown($text);
+ print "</div>";
+ }
+}
+
+
+
+sub Markdown {
+#
+# Main function. The order in which other subs are called here is
+# essential. Link and image substitutions need to happen before
+# _EscapeSpecialChars(), so that any *'s or _'s in the <a>
+# and <img> tags get encoded.
+#
+ my $text = shift;
+
+ # Clear the global hashes. If we don't clear these, you get conflicts
+ # from other articles when generating a page which contains more than
+ # one article (e.g. an index page that shows the N most recent
+ # articles):
+ %g_urls = ();
+ %g_titles = ();
+ %g_html_blocks = ();
+
+
+ # Standardize line endings:
+ $text =~ s{\r\n}{\n}g; # DOS to Unix
+ $text =~ s{\r}{\n}g; # Mac to Unix
+
+ # Make sure $text ends with a couple of newlines:
+ $text .= "\n\n";
+
+ # Convert all tabs to spaces.
+ $text = _Detab($text);
+
+ # Strip any lines consisting only of spaces and tabs.
+ # This makes subsequent regexen easier to write, because we can
+ # match consecutive blank lines with /\n+/ instead of something
+ # contorted like /[ \t]*\n+/ .
+ $text =~ s/^[ \t]+$//mg;
+
+ # Turn block-level HTML blocks into hash entries
+ $text = _HashHTMLBlocks($text);
+
+ # Strip link definitions, store in hashes.
+ $text = _StripLinkDefinitions($text);
+
+ $text = _RunBlockGamut($text);
+
+ $text = _UnescapeSpecialChars($text);
+
+ return $text . "\n";
+}
+
+
+sub _StripLinkDefinitions {
+#
+# Strips link definitions from text, stores the URLs and titles in
+# hash references.
+#
+ my $text = shift;
+ my $less_than_tab = $g_tab_width - 1;
+
+ # Link defs are in the form: ^[id]: url "optional title"
+ while ($text =~ s{
+ ^[ ]{0,$less_than_tab}\[(.+)\]: # id = $1
+ [ \t]*
+ \n? # maybe *one* newline
+ [ \t]*
+ <?(\S+?)>? # url = $2
+ [ \t]*
+ \n? # maybe one newline
+ [ \t]*
+ (?:
+ (?<=\s) # lookbehind for whitespace
+ ["(]
+ (.+?) # title = $3
+ [")]
+ [ \t]*
+ )? # title is optional
+ (?:\n+|\Z)
+ }
+ {}mx) {
+ $g_urls{lc $1} = _EncodeAmpsAndAngles( $2 ); # Link IDs are case-insensitive
+ if ($3) {
+ $g_titles{lc $1} = $3;
+ $g_titles{lc $1} =~ s/"/&quot;/g;
+ }
+ }
+
+ return $text;
+}
+
+
+sub _HashHTMLBlocks {
+ my $text = shift;
+ my $less_than_tab = $g_tab_width - 1;
+
+ # Hashify HTML blocks:
+ # We only want to do this for block-level HTML tags, such as headers,
+ # lists, and tables. That's because we still want to wrap <p>s around
+ # "paragraphs" that are wrapped in non-block-level tags, such as anchors,
+ # phrase emphasis, and spans. The list of tags we're looking for is
+ # hard-coded:
+ my $block_tags_a = qr/p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|ins|del/;
+ my $block_tags_b = qr/p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math/;
+
+ # First, look for nested blocks, e.g.:
+ # <div>
+ # <div>
+ # tags for inner block must be indented.
+ # </div>
+ # </div>
+ #
+ # The outermost tags must start at the left margin for this to match, and
+ # the inner nested divs must be indented.
+ # We need to do this before the next, more liberal match, because the next
+ # match will start at the first `<div>` and stop at the first `</div>`.
+ $text =~ s{
+ ( # save in $1
+ ^ # start of line (with /m)
+ <($block_tags_a) # start tag = $2
+ \b # word break
+ (.*\n)*? # any number of lines, minimally matching
+ </\2> # the matching end tag
+ [ \t]* # trailing spaces/tabs
+ (?=\n+|\Z) # followed by a newline or end of document
+ )
+ }{
+ my $key = md5_hex($1);
+ $g_html_blocks{$key} = $1;
+ "\n\n" . $key . "\n\n";
+ }egmx;
+
+
+ #
+ # Now match more liberally, simply from `\n<tag>` to `</tag>\n`
+ #
+ $text =~ s{
+ ( # save in $1
+ ^ # start of line (with /m)
+ <($block_tags_b) # start tag = $2
+ \b # word break
+ (.*\n)*? # any number of lines, minimally matching
+ .*</\2> # the matching end tag
+ [ \t]* # trailing spaces/tabs
+ (?=\n+|\Z) # followed by a newline or end of document
+ )
+ }{
+ my $key = md5_hex($1);
+ $g_html_blocks{$key} = $1;
+ "\n\n" . $key . "\n\n";
+ }egmx;
+ # Special case just for <hr />. It was easier to make a special case than
+ # to make the other regex more complicated.
+ $text =~ s{
+ (?:
+ (?<=\n\n) # Starting after a blank line
+ | # or
+ \A\n? # the beginning of the doc
+ )
+ ( # save in $1
+ [ ]{0,$less_than_tab}
+ <(hr) # start tag = $2
+ \b # word break
+ ([^<>])*? #
+ /?> # the matching end tag
+ [ \t]*
+ (?=\n{2,}|\Z) # followed by a blank line or end of document
+ )
+ }{
+ my $key = md5_hex($1);
+ $g_html_blocks{$key} = $1;
+ "\n\n" . $key . "\n\n";
+ }egx;
+
+ # Special case for standalone HTML comments:
+ $text =~ s{
+ (?:
+ (?<=\n\n) # Starting after a blank line
+ | # or
+ \A\n? # the beginning of the doc
+ )
+ ( # save in $1
+ [ ]{0,$less_than_tab}
+ (?s:
+ <!
+ (--.*?--\s*)+
+ >
+ )
+ [ \t]*
+ (?=\n{2,}|\Z) # followed by a blank line or end of document
+ )
+ }{
+ my $key = md5_hex($1);
+ $g_html_blocks{$key} = $1;
+ "\n\n" . $key . "\n\n";
+ }egx;
+
+
+ return $text;
+}
+
+
+sub _RunBlockGamut {
+#
+# These are all the transformations that form block-level
+# tags like paragraphs, headers, and list items.
+#
+ my $text = shift;
+
+ $text = _DoHeaders($text);
+
+ # Do Horizontal Rules:
+ $text =~ s{^[ ]{0,2}([ ]?\*[ ]?){3,}[ \t]*$}{\n<hr$g_empty_element_suffix\n}gmx;
+ $text =~ s{^[ ]{0,2}([ ]? -[ ]?){3,}[ \t]*$}{\n<hr$g_empty_element_suffix\n}gmx;
+ $text =~ s{^[ ]{0,2}([ ]? _[ ]?){3,}[ \t]*$}{\n<hr$g_empty_element_suffix\n}gmx;
+
+ $text = _DoLists($text);
+
+ $text = _DoCodeBlocks($text);
+
+ $text = _DoBlockQuotes($text);
+
+ # We already ran _HashHTMLBlocks() before, in Markdown(), but that
+ # was to escape raw HTML in the original Markdown source. This time,
+ # we're escaping the markup we've just created, so that we don't wrap
+ # <p> tags around block-level tags.
+ $text = _HashHTMLBlocks($text);
+
+ $text = _FormParagraphs($text);
+
+ return $text;
+}
+
+
+sub _RunSpanGamut {
+#
+# These are all the transformations that occur *within* block-level
+# tags like paragraphs, headers, and list items.
+#
+ my $text = shift;
+
+ $text = _DoCodeSpans($text);
+
+ $text = _EscapeSpecialChars($text);
+
+ # Process anchor and image tags. Images must come first,
+ # because ![foo][f] looks like an anchor.
+ $text = _DoImages($text);
+ $text = _DoAnchors($text);
+
+ # Make links out of things like `<http://example.com/>`
+ # Must come after _DoAnchors(), because you can use < and >
+ # delimiters in inline links like [this](<url>).
+ $text = _DoAutoLinks($text);
+
+ $text = _EncodeAmpsAndAngles($text);
+
+ $text = _DoItalicsAndBold($text);
+
+ # Do hard breaks:
+ $text =~ s/ {2,}\n/ <br$g_empty_element_suffix\n/g;
+
+ return $text;
+}
+
+
+sub _EscapeSpecialChars {
+ my $text = shift;
+ my $tokens ||= _TokenizeHTML($text);
+
+ $text = ''; # rebuild $text from the tokens
+# my $in_pre = 0; # Keep track of when we're inside <pre> or <code> tags.
+# my $tags_to_skip = qr!<(/?)(?:pre|code|kbd|script|math)[\s>]!;
+
+ foreach my $cur_token (@$tokens) {
+ if ($cur_token->[0] eq "tag") {
+ # Within tags, encode * and _ so they don't conflict
+ # with their use in Markdown for italics and strong.
+ # We're replacing each such character with its
+ # corresponding MD5 checksum value; this is likely
+ # overkill, but it should prevent us from colliding
+ # with the escape values by accident.
+ $cur_token->[1] =~ s! \* !$g_escape_table{'*'}!gx;
+ $cur_token->[1] =~ s! _ !$g_escape_table{'_'}!gx;
+ $text .= $cur_token->[1];
+ } else {
+ my $t = $cur_token->[1];
+ $t = _EncodeBackslashEscapes($t);
+ $text .= $t;
+ }
+ }
+ return $text;
+}
+
+
+sub _DoAnchors {
+#
+# Turn Markdown link shortcuts into XHTML <a> tags.
+#
+ my $text = shift;
+
+ #
+ # First, handle reference-style links: [link text] [id]
+ #
+ $text =~ s{
+ ( # wrap whole match in $1
+ \[
+ ($g_nested_brackets) # link text = $2
+ \]
+
+ [ ]? # one optional space
+ (?:\n[ ]*)? # one optional newline followed by spaces
+
+ \[
+ (.*?) # id = $3
+ \]
+ )
+ }{
+ my $result;
+ my $whole_match = $1;
+ my $link_text = $2;
+ my $link_id = lc $3;
+
+ if ($link_id eq "") {
+ $link_id = lc $link_text; # for shortcut links like [this][].
+ }
+
+ if (defined $g_urls{$link_id}) {
+ my $url = $g_urls{$link_id};
+ $url =~ s! \* !$g_escape_table{'*'}!gx; # We've got to encode these to avoid
+ $url =~ s! _ !$g_escape_table{'_'}!gx; # conflicting with italics/bold.
+ $result = "<a href=\"$url\"";
+ if ( defined $g_titles{$link_id} ) {
+ my $title = $g_titles{$link_id};
+ $title =~ s! \* !$g_escape_table{'*'}!gx;
+ $title =~ s! _ !$g_escape_table{'_'}!gx;
+ $result .= " title=\"$title\"";
+ }
+ $result .= ">$link_text</a>";
+ }
+ else {
+ $result = $whole_match;
+ }
+ $result;
+ }xsge;
+
+ #
+ # Next, inline-style links: [link text](url "optional title")
+ #
+ $text =~ s{
+ ( # wrap whole match in $1
+ \[
+ ($g_nested_brackets) # link text = $2
+ \]
+ \( # literal paren
+ [ \t]*
+ <?(.*?)>? # href = $3
+ [ \t]*
+ ( # $4
+ (['"]) # quote char = $5
+ (.*?) # Title = $6
+ \5 # matching quote
+ )? # title is optional
+ \)
+ )
+ }{
+ my $result;
+ my $whole_match = $1;
+ my $link_text = $2;
+ my $url = $3;
+ my $title = $6;
+
+ $url =~ s! \* !$g_escape_table{'*'}!gx; # We've got to encode these to avoid
+ $url =~ s! _ !$g_escape_table{'_'}!gx; # conflicting with italics/bold.
+ $result = "<a href=\"$url\"";
+
+ if (defined $title) {
+ $title =~ s/"/&quot;/g;
+ $title =~ s! \* !$g_escape_table{'*'}!gx;
+ $title =~ s! _ !$g_escape_table{'_'}!gx;
+ $result .= " title=\"$title\"";
+ }
+
+ $result .= ">$link_text</a>";
+
+ $result;
+ }xsge;
+
+ return $text;
+}
+
+
+sub _DoImages {
+#
+# Turn Markdown image shortcuts into <img> tags.
+#
+ my $text = shift;
+
+ #
+ # First, handle reference-style labeled images: ![alt text][id]
+ #
+ $text =~ s{
+ ( # wrap whole match in $1
+ !\[
+ (.*?) # alt text = $2
+ \]
+
+ [ ]? # one optional space
+ (?:\n[ ]*)? # one optional newline followed by spaces
+
+ \[
+ (.*?) # id = $3
+ \]
+
+ )
+ }{
+ my $result;
+ my $whole_match = $1;
+ my $alt_text = $2;
+ my $link_id = lc $3;
+
+ if ($link_id eq "") {
+ $link_id = lc $alt_text; # for shortcut links like ![this][].
+ }
+
+ $alt_text =~ s/"/&quot;/g;
+ if (defined $g_urls{$link_id}) {
+ my $url = $g_urls{$link_id};
+ $url =~ s! \* !$g_escape_table{'*'}!gx; # We've got to encode these to avoid
+ $url =~ s! _ !$g_escape_table{'_'}!gx; # conflicting with italics/bold.
+ $result = "<img src=\"$url\" alt=\"$alt_text\"";
+ if (defined $g_titles{$link_id}) {
+ my $title = $g_titles{$link_id};
+ $title =~ s! \* !$g_escape_table{'*'}!gx;
+ $title =~ s! _ !$g_escape_table{'_'}!gx;
+ $result .= " title=\"$title\"";
+ }
+ $result .= $g_empty_element_suffix;
+ }
+ else {
+ # If there's no such link ID, leave intact:
+ $result = $whole_match;
+ }
+
+ $result;
+ }xsge;
+
+ #
+ # Next, handle inline images: ![alt text](url "optional title")
+ # Don't forget: encode * and _
+
+ $text =~ s{
+ ( # wrap whole match in $1
+ !\[
+ (.*?) # alt text = $2
+ \]
+ \( # literal paren
+ [ \t]*
+ <?(\S+?)>? # src url = $3
+ [ \t]*
+ ( # $4
+ (['"]) # quote char = $5
+ (.*?) # title = $6
+ \5 # matching quote
+ [ \t]*
+ )? # title is optional
+ \)
+ )
+ }{
+ my $result;
+ my $whole_match = $1;
+ my $alt_text = $2;
+ my $url = $3;
+ my $title = '';
+ if (defined($6)) {
+ $title = $6;
+ }
+
+ $alt_text =~ s/"/&quot;/g;
+ $title =~ s/"/&quot;/g;
+ $url =~ s! \* !$g_escape_table{'*'}!gx; # We've got to encode these to avoid
+ $url =~ s! _ !$g_escape_table{'_'}!gx; # conflicting with italics/bold.
+ $result = "<img src=\"$url\" alt=\"$alt_text\"";
+ if (defined $title) {
+ $title =~ s! \* !$g_escape_table{'*'}!gx;
+ $title =~ s! _ !$g_escape_table{'_'}!gx;
+ $result .= " title=\"$title\"";
+ }
+ $result .= $g_empty_element_suffix;
+
+ $result;
+ }xsge;
+
+ return $text;
+}
+
+
+sub _DoHeaders {
+ my $text = shift;
+
+ # Setext-style headers:
+ # Header 1
+ # ========
+ #
+ # Header 2
+ # --------
+ #
+ $text =~ s{ ^(.+)[ \t]*\n=+[ \t]*\n+ }{
+ "<h1>" . _RunSpanGamut($1) . "</h1>\n\n";
+ }egmx;
+
+ $text =~ s{ ^(.+)[ \t]*\n-+[ \t]*\n+ }{
+ "<h2>" . _RunSpanGamut($1) . "</h2>\n\n";
+ }egmx;
+
+
+ # atx-style headers:
+ # # Header 1
+ # ## Header 2
+ # ## Header 2 with closing hashes ##
+ # ...
+ # ###### Header 6
+ #
+ $text =~ s{
+ ^(\#{1,6}) # $1 = string of #'s
+ [ \t]*
+ (.+?) # $2 = Header text
+ [ \t]*
+ \#* # optional closing #'s (not counted)
+ \n+
+ }{
+ my $h_level = length($1);
+ "<h$h_level>" . _RunSpanGamut($2) . "</h$h_level>\n\n";
+ }egmx;
+
+ return $text;
+}
+
+
+sub _DoLists {
+#
+# Form HTML ordered (numbered) and unordered (bulleted) lists.
+#
+ my $text = shift;
+ my $less_than_tab = $g_tab_width - 1;
+
+ # Re-usable patterns to match list item bullets and number markers:
+ my $marker_ul = qr/[*+-]/;
+ my $marker_ol = qr/\d+[.]/;
+ my $marker_any = qr/(?:$marker_ul|$marker_ol)/;
+
+ # Re-usable pattern to match any entirel ul or ol list:
+ my $whole_list = qr{
+ ( # $1 = whole list
+ ( # $2
+ [ ]{0,$less_than_tab}
+ (${marker_any}) # $3 = first list item marker
+ [ \t]+
+ )
+ (?s:.+?)
+ ( # $4
+ \z
+ |
+ \n{2,}
+ (?=\S)
+ (?! # Negative lookahead for another list item marker
+ [ \t]*
+ ${marker_any}[ \t]+
+ )
+ )
+ )
+ }mx;
+
+ # We use a different prefix before nested lists than top-level lists.
+ # See extended comment in _ProcessListItems().
+ #
+ # Note: There's a bit of duplication here. My original implementation
+ # created a scalar regex pattern as the conditional result of the test on
+ # $g_list_level, and then only ran the $text =~ s{...}{...}egmx
+ # substitution once, using the scalar as the pattern. This worked,
+ # everywhere except when running under MT on my hosting account at Pair
+ # Networks. There, this caused all rebuilds to be killed by the reaper (or
+ # perhaps they crashed, but that seems incredibly unlikely given that the
+ # same script on the same server ran fine *except* under MT. I've spent
+ # more time trying to figure out why this is happening than I'd like to
+ # admit. My only guess, backed up by the fact that this workaround works,
+ # is that Perl optimizes the substition when it can figure out that the
+ # pattern will never change, and when this optimization isn't on, we run
+ # afoul of the reaper. Thus, the slightly redundant code to that uses two
+ # static s/// patterns rather than one conditional pattern.
+
+ if ($g_list_level) {
+ $text =~ s{
+ ^
+ $whole_list
+ }{
+ my $list = $1;
+ my $list_type = ($3 =~ m/$marker_ul/) ? "ul" : "ol";
+ # Turn double returns into triple returns, so that we can make a
+ # paragraph for the last item in a list, if necessary:
+ $list =~ s/\n{2,}/\n\n\n/g;
+ my $result = _ProcessListItems($list, $marker_any);
+ $result = "<$list_type>\n" . $result . "</$list_type>\n";
+ $result;
+ }egmx;
+ }
+ else {
+ $text =~ s{
+ (?:(?<=\n\n)|\A\n?)
+ $whole_list
+ }{
+ my $list = $1;
+ my $list_type = ($3 =~ m/$marker_ul/) ? "ul" : "ol";
+ # Turn double returns into triple returns, so that we can make a
+ # paragraph for the last item in a list, if necessary:
+ $list =~ s/\n{2,}/\n\n\n/g;
+ my $result = _ProcessListItems($list, $marker_any);
+ $result = "<$list_type>\n" . $result . "</$list_type>\n";
+ $result;
+ }egmx;
+ }
+
+
+ return $text;
+}
+
+
+sub _ProcessListItems {
+#
+# Process the contents of a single ordered or unordered list, splitting it
+# into individual list items.
+#
+
+ my $list_str = shift;
+ my $marker_any = shift;
+
+
+ # The $g_list_level global keeps track of when we're inside a list.
+ # Each time we enter a list, we increment it; when we leave a list,
+ # we decrement. If it's zero, we're not in a list anymore.
+ #
+ # We do this because when we're not inside a list, we want to treat
+ # something like this:
+ #
+ # I recommend upgrading to version
+ # 8. Oops, now this line is treated
+ # as a sub-list.
+ #
+ # As a single paragraph, despite the fact that the second line starts
+ # with a digit-period-space sequence.
+ #
+ # Whereas when we're inside a list (or sub-list), that line will be
+ # treated as the start of a sub-list. What a kludge, huh? This is
+ # an aspect of Markdown's syntax that's hard to parse perfectly
+ # without resorting to mind-reading. Perhaps the solution is to
+ # change the syntax rules such that sub-lists must start with a
+ # starting cardinal number; e.g. "1." or "a.".
+
+ $g_list_level++;
+
+ # trim trailing blank lines:
+ $list_str =~ s/\n{2,}\z/\n/;
+
+
+ $list_str =~ s{
+ (\n)? # leading line = $1
+ (^[ \t]*) # leading whitespace = $2
+ ($marker_any) [ \t]+ # list marker = $3
+ ((?s:.+?) # list item text = $4
+ (\n{1,2}))
+ (?= \n* (\z | \2 ($marker_any) [ \t]+))
+ }{
+ my $item = $4;
+ my $leading_line = $1;
+ my $leading_space = $2;
+
+ if ($leading_line or ($item =~ m/\n{2,}/)) {
+ $item = _RunBlockGamut(_Outdent($item));
+ }
+ else {
+ # Recursion for sub-lists:
+ $item = _DoLists(_Outdent($item));
+ chomp $item;
+ $item = _RunSpanGamut($item);
+ }
+
+ "<li>" . $item . "</li>\n";
+ }egmx;
+
+ $g_list_level--;
+ return $list_str;
+}
+
+
+
+sub _DoCodeBlocks {
+#
+# Process Markdown `<pre><code>` blocks.
+#
+
+ my $text = shift;
+
+ $text =~ s{
+ (?:\n\n|\A)
+ ( # $1 = the code block -- one or more lines, starting with a space/tab
+ (?:
+ (?:[ ]{$g_tab_width} | \t) # Lines must start with a tab or a tab-width of spaces
+ .*\n+
+ )+
+ )
+ ((?=^[ ]{0,$g_tab_width}\S)|\Z) # Lookahead for non-space at line-start, or end of doc
+ }{
+ my $codeblock = $1;
+ my $result; # return value
+
+ $codeblock = _EncodeCode(_Outdent($codeblock));
+ $codeblock = _Detab($codeblock);
+ $codeblock =~ s/\A\n+//; # trim leading newlines
+ $codeblock =~ s/\s+\z//; # trim trailing whitespace
+
+ $result = "\n\n<pre><code>" . $codeblock . "\n</code></pre>\n\n";
+
+ $result;
+ }egmx;
+
+ return $text;
+}
+
+
+sub _DoCodeSpans {
+#
+# * Backtick quotes are used for <code></code> spans.
+#
+# * You can use multiple backticks as the delimiters if you want to
+# include literal backticks in the code span. So, this input:
+#
+# Just type ``foo `bar` baz`` at the prompt.
+#
+# Will translate to:
+#
+# <p>Just type <code>foo `bar` baz</code> at the prompt.</p>
+#
+# There's no arbitrary limit to the number of backticks you
+# can use as delimters. If you need three consecutive backticks
+# in your code, use four for delimiters, etc.
+#
+# * You can use spaces to get literal backticks at the edges:
+#
+# ... type `` `bar` `` ...
+#
+# Turns to:
+#
+# ... type <code>`bar`</code> ...
+#
+
+ my $text = shift;
+
+ $text =~ s@
+ (`+) # $1 = Opening run of `
+ (.+?) # $2 = The code block
+ (?<!`)
+ \1 # Matching closer
+ (?!`)
+ @
+ my $c = "$2";
+ $c =~ s/^[ \t]*//g; # leading whitespace
+ $c =~ s/[ \t]*$//g; # trailing whitespace
+ $c = _EncodeCode($c);
+ "<code>$c</code>";
+ @egsx;
+
+ return $text;
+}
+
+
+sub _EncodeCode {
+#
+# Encode/escape certain characters inside Markdown code runs.
+# The point is that in code, these characters are literals,
+# and lose their special Markdown meanings.
+#
+ local $_ = shift;
+
+ # Encode all ampersands; HTML entities are not
+ # entities within a Markdown code span.
+ s/&/&amp;/g;
+
+ # Encode $'s, but only if we're running under Blosxom.
+ # (Blosxom interpolates Perl variables in article bodies.)
+ {
+ no warnings 'once';
+ if (defined($blosxom::version)) {
+ s/\$/&#036;/g;
+ }
+ }
+
+
+ # Do the angle bracket song and dance:
+ s! < !&lt;!gx;
+ s! > !&gt;!gx;
+
+ # Now, escape characters that are magic in Markdown:
+ s! \* !$g_escape_table{'*'}!gx;
+ s! _ !$g_escape_table{'_'}!gx;
+ s! { !$g_escape_table{'{'}!gx;
+ s! } !$g_escape_table{'}'}!gx;
+ s! \[ !$g_escape_table{'['}!gx;
+ s! \] !$g_escape_table{']'}!gx;
+ s! \\ !$g_escape_table{'\\'}!gx;
+
+ return $_;
+}
+
+
+sub _DoItalicsAndBold {
+ my $text = shift;
+
+ # <strong> must go first:
+ $text =~ s{ (\*\*|__) (?=\S) (.+?[*_]*) (?<=\S) \1 }
+ {<strong>$2</strong>}gsx;
+
+ $text =~ s{ (\*|_) (?=\S) (.+?) (?<=\S) \1 }
+ {<em>$2</em>}gsx;
+
+ return $text;
+}
+
+
+sub _DoBlockQuotes {
+ my $text = shift;
+
+ $text =~ s{
+ ( # Wrap whole match in $1
+ (
+ ^[ \t]*>[ \t]? # '>' at the start of a line
+ .+\n # rest of the first line
+ (.+\n)* # subsequent consecutive lines
+ \n* # blanks
+ )+
+ )
+ }{
+ my $bq = $1;
+ $bq =~ s/^[ \t]*>[ \t]?//gm; # trim one level of quoting
+ $bq =~ s/^[ \t]+$//mg; # trim whitespace-only lines
+ $bq = _RunBlockGamut($bq); # recurse
+
+ $bq =~ s/^/ /g;
+ # These leading spaces screw with <pre> content, so we need to fix that:
+ $bq =~ s{
+ (\s*<pre>.+?</pre>)
+ }{
+ my $pre = $1;
+ $pre =~ s/^ //mg;
+ $pre;
+ }egsx;
+
+ "<blockquote>\n$bq\n</blockquote>\n\n";
+ }egmx;
+
+
+ return $text;
+}
+
+
+sub _FormParagraphs {
+#
+# Params:
+# $text - string to process with html <p> tags
+#
+ my $text = shift;
+
+ # Strip leading and trailing lines:
+ $text =~ s/\A\n+//;
+ $text =~ s/\n+\z//;
+
+ my @grafs = split(/\n{2,}/, $text);
+
+ #
+ # Wrap <p> tags.
+ #
+ foreach (@grafs) {
+ unless (defined( $g_html_blocks{$_} )) {
+ $_ = _RunSpanGamut($_);
+ s/^([ \t]*)/<p>/;
+ $_ .= "</p>";
+ }
+ }
+
+ #
+ # Unhashify HTML blocks
+ #
+ foreach (@grafs) {
+ if (defined( $g_html_blocks{$_} )) {
+ $_ = $g_html_blocks{$_};
+ }
+ }
+
+ return join "\n\n", @grafs;
+}
+
+
+sub _EncodeAmpsAndAngles {
+# Smart processing for ampersands and angle brackets that need to be encoded.
+
+ my $text = shift;
+
+ # Ampersand-encoding based entirely on Nat Irons's Amputator MT plugin:
+ # http://bumppo.net/projects/amputator/
+ $text =~ s/&(?!#?[xX]?(?:[0-9a-fA-F]+|\w+);)/&amp;/g;
+
+ # Encode naked <'s
+ $text =~ s{<(?![a-z/?\$!])}{&lt;}gi;
+
+ return $text;
+}
+
+
+sub _EncodeBackslashEscapes {
+#
+# Parameter: String.
+# Returns: The string, with after processing the following backslash
+# escape sequences.
+#
+ local $_ = shift;
+
+ s! \\\\ !$g_escape_table{'\\'}!gx; # Must process escaped backslashes first.
+ s! \\` !$g_escape_table{'`'}!gx;
+ s! \\\* !$g_escape_table{'*'}!gx;
+ s! \\_ !$g_escape_table{'_'}!gx;
+ s! \\\{ !$g_escape_table{'{'}!gx;
+ s! \\\} !$g_escape_table{'}'}!gx;
+ s! \\\[ !$g_escape_table{'['}!gx;
+ s! \\\] !$g_escape_table{']'}!gx;
+ s! \\\( !$g_escape_table{'('}!gx;
+ s! \\\) !$g_escape_table{')'}!gx;
+ s! \\> !$g_escape_table{'>'}!gx;
+ s! \\\# !$g_escape_table{'#'}!gx;
+ s! \\\+ !$g_escape_table{'+'}!gx;
+ s! \\\- !$g_escape_table{'-'}!gx;
+ s! \\\. !$g_escape_table{'.'}!gx;
+ s{ \\! }{$g_escape_table{'!'}}gx;
+
+ return $_;
+}
+
+
+sub _DoAutoLinks {
+ my $text = shift;
+
+ $text =~ s{<((https?|ftp):[^'">\s]+)>}{<a href="$1">$1</a>}gi;
+
+ # Email addresses: <address@domain.foo>
+ $text =~ s{
+ <
+ (?:mailto:)?
+ (
+ [-.\w]+
+ \@
+ [-a-z0-9]+(\.[-a-z0-9]+)*\.[a-z]+
+ )
+ >
+ }{
+ _EncodeEmailAddress( _UnescapeSpecialChars($1) );
+ }egix;
+
+ return $text;
+}
+
+
+sub _EncodeEmailAddress {
+#
+# Input: an email address, e.g. "foo@example.com"
+#
+# Output: the email address as a mailto link, with each character
+# of the address encoded as either a decimal or hex entity, in
+# the hopes of foiling most address harvesting spam bots. E.g.:
+#
+# <a href="&#x6D;&#97;&#105;&#108;&#x74;&#111;:&#102;&#111;&#111;&#64;&#101;
+# x&#x61;&#109;&#x70;&#108;&#x65;&#x2E;&#99;&#111;&#109;">&#102;&#111;&#111;
+# &#64;&#101;x&#x61;&#109;&#x70;&#108;&#x65;&#x2E;&#99;&#111;&#109;</a>
+#
+# Based on a filter by Matthew Wickline, posted to the BBEdit-Talk
+# mailing list: <http://tinyurl.com/yu7ue>
+#
+
+ my $addr = shift;
+
+ srand;
+ my @encode = (
+ sub { '&#' . ord(shift) . ';' },
+ sub { '&#x' . sprintf( "%X", ord(shift) ) . ';' },
+ sub { shift },
+ );
+
+ $addr = "mailto:" . $addr;
+
+ $addr =~ s{(.)}{
+ my $char = $1;
+ if ( $char eq '@' ) {
+ # this *must* be encoded. I insist.
+ $char = $encode[int rand 1]->($char);
+ } elsif ( $char ne ':' ) {
+ # leave ':' alone (to spot mailto: later)
+ my $r = rand;
+ # roughly 10% raw, 45% hex, 45% dec
+ $char = (
+ $r > .9 ? $encode[2]->($char) :
+ $r < .45 ? $encode[1]->($char) :
+ $encode[0]->($char)
+ );
+ }
+ $char;
+ }gex;
+
+ $addr = qq{<a href="$addr">$addr</a>};
+ $addr =~ s{">.+?:}{">}; # strip the mailto: from the visible part
+
+ return $addr;
+}
+
+
+sub _UnescapeSpecialChars {
+#
+# Swap back in all the special characters we've hidden.
+#
+ my $text = shift;
+
+ while( my($char, $hash) = each(%g_escape_table) ) {
+ $text =~ s/$hash/$char/g;
+ }
+ return $text;
+}
+
+
+sub _TokenizeHTML {
+#
+# Parameter: String containing HTML markup.
+# Returns: Reference to an array of the tokens comprising the input
+# string. Each token is either a tag (possibly with nested,
+# tags contained therein, such as <a href="<MTFoo>">, or a
+# run of text between tags. Each element of the array is a
+# two-element array; the first is either 'tag' or 'text';
+# the second is the actual value.
+#
+#
+# Derived from the _tokenize() subroutine from Brad Choate's MTRegex plugin.
+# <http://www.bradchoate.com/past/mtregex.php>
+#
+
+ my $str = shift;
+ my $pos = 0;
+ my $len = length $str;
+ my @tokens;
+
+ my $depth = 6;
+ my $nested_tags = join('|', ('(?:<[a-z/!$](?:[^<>]') x $depth) . (')*>)' x $depth);
+ my $match = qr/(?s: <! ( -- .*? -- \s* )+ > ) | # comment
+ (?s: <\? .*? \?> ) | # processing instruction
+ $nested_tags/ix; # nested tags
+
+ while ($str =~ m/($match)/g) {
+ my $whole_tag = $1;
+ my $sec_start = pos $str;
+ my $tag_start = $sec_start - length $whole_tag;
+ if ($pos < $tag_start) {
+ push @tokens, ['text', substr($str, $pos, $tag_start - $pos)];
+ }
+ push @tokens, ['tag', $whole_tag];
+ $pos = pos $str;
+ }
+ push @tokens, ['text', substr($str, $pos, $len - $pos)] if $pos < $len;
+ \@tokens;
+}
+
+
+sub _Outdent {
+#
+# Remove one level of line-leading tabs or spaces
+#
+ my $text = shift;
+
+ $text =~ s/^(\t|[ ]{1,$g_tab_width})//gm;
+ return $text;
+}
+
+
+sub _Detab {
+#
+# Cribbed from a post by Bart Lateur:
+# <http://www.nntp.perl.org/group/perl.macperl.anyperl/154>
+#
+ my $text = shift;
+
+ $text =~ s{(.*?)\t}{$1.(' ' x ($g_tab_width - length($1) % $g_tab_width))}ge;
+ return $text;
+}
+
+
+1;
+
+__END__
+
+
+=pod
+
+=head1 NAME
+
+B<Markdown>
+
+
+=head1 SYNOPSIS
+
+B<Markdown.pl> [ B<--html4tags> ] [ B<--version> ] [ B<-shortversion> ]
+ [ I<file> ... ]
+
+
+=head1 DESCRIPTION
+
+Markdown is a text-to-HTML filter; it translates an easy-to-read /
+easy-to-write structured text format into HTML. Markdown's text format
+is most similar to that of plain text email, and supports features such
+as headers, *emphasis*, code blocks, blockquotes, and links.
+
+Markdown's syntax is designed not as a generic markup language, but
+specifically to serve as a front-end to (X)HTML. You can use span-level
+HTML tags anywhere in a Markdown document, and you can use block level
+HTML tags (like <div> and <table> as well).
+
+For more information about Markdown's syntax, see:
+
+ http://daringfireball.net/projects/markdown/
+
+
+=head1 OPTIONS
+
+Use "--" to end switch parsing. For example, to open a file named "-z", use:
+
+ Markdown.pl -- -z
+
+=over 4
+
+
+=item B<--html4tags>
+
+Use HTML 4 style for empty element tags, e.g.:
+
+ <br>
+
+instead of Markdown's default XHTML style tags, e.g.:
+
+ <br />
+
+
+=item B<-v>, B<--version>
+
+Display Markdown's version number and copyright information.
+
+
+=item B<-s>, B<--shortversion>
+
+Display the short-form version number.
+
+
+=back
+
+
+
+=head1 BUGS
+
+To file bug reports or feature requests (other than topics listed in the
+Caveats section above) please send email to:
+
+ support@daringfireball.net
+
+Please include with your report: (1) the example input; (2) the output
+you expected; (3) the output Markdown actually produced.
+
+
+=head1 VERSION HISTORY
+
+See the readme file for detailed release notes for this version.
+
+1.0.1 - 14 Dec 2004
+
+1.0 - 28 Aug 2004
+
+
+=head1 AUTHOR
+
+ John Gruber
+ http://daringfireball.net
+
+ PHP port and other contributions by Michel Fortin
+ http://michelf.com
+
+
+=head1 COPYRIGHT AND LICENSE
+
+Copyright (c) 2003-2004 John Gruber
+<http://daringfireball.net/>
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+* Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+* Neither the name "Markdown" nor the names of its contributors may
+ be used to endorse or promote products derived from this software
+ without specific prior written permission.
+
+This software is provided by the copyright holders and contributors "as
+is" and any express or implied warranties, including, but not limited
+to, the implied warranties of merchantability and fitness for a
+particular purpose are disclaimed. In no event shall the copyright owner
+or contributors be liable for any direct, indirect, incidental, special,
+exemplary, or consequential damages (including, but not limited to,
+procurement of substitute goods or services; loss of use, data, or
+profits; or business interruption) however caused and on any theory of
+liability, whether in contract, strict liability, or tort (including
+negligence or otherwise) arising in any way out of the use of this
+software, even if advised of the possibility of such damage.
+
+=cut