* There can only be one hook for each shortcode. Which means that if another
* plugin has a similar shortcode, it will override yours or yours will override
* theirs depending on which order the plugins are included and/or ran.
- *
+ *
* Simplest example of a shortcode tag using the API:
*
* <code>
return $content;
$pattern = get_shortcode_regex();
- return preg_replace_callback('/'.$pattern.'/s', 'do_shortcode_tag', $content);
+ return preg_replace_callback( "/$pattern/s", 'do_shortcode_tag', $content );
}
/**
* The regular expression combines the shortcode tags in the regular expression
* in a regex class.
*
+ * The regular expression contains 6 different sub matches to help with parsing.
+ *
+ * 1 - An extra [ to allow for escaping shortcodes with double [[]]
+ * 2 - The shortcode name
+ * 3 - The shortcode argument list
+ * 4 - The self closing /
+ * 5 - The content of a shortcode when it wraps some content.
+ * 6 - An extra ] to allow for escaping shortcodes with double [[]]
+ *
* @since 2.5
* @uses $shortcode_tags
*
$tagnames = array_keys($shortcode_tags);
$tagregexp = join( '|', array_map('preg_quote', $tagnames) );
- return '\[('.$tagregexp.')\b(.*?)(?:(\/))?\](?:(.+?)\[\/\1\])?';
+ // WARNING! Do not change this regex without changing do_shortcode_tag() and strip_shortcode_tag()
+ // Also, see shortcode_unautop() and shortcode.js.
+ return
+ '\\[' // Opening bracket
+ . '(\\[?)' // 1: Optional second opening bracket for escaping shortcodes: [[tag]]
+ . "($tagregexp)" // 2: Shortcode name
+ . '(?![\\w-])' // Not followed by word character or hyphen
+ . '(' // 3: Unroll the loop: Inside the opening shortcode tag
+ . '[^\\]\\/]*' // Not a closing bracket or forward slash
+ . '(?:'
+ . '\\/(?!\\])' // A forward slash not followed by a closing bracket
+ . '[^\\]\\/]*' // Not a closing bracket or forward slash
+ . ')*?'
+ . ')'
+ . '(?:'
+ . '(\\/)' // 4: Self closing tag ...
+ . '\\]' // ... and closing bracket
+ . '|'
+ . '\\]' // Closing bracket
+ . '(?:'
+ . '(' // 5: Unroll the loop: Optionally, anything between the opening and closing shortcode tags
+ . '[^\\[]*+' // Not an opening bracket
+ . '(?:'
+ . '\\[(?!\\/\\2\\])' // An opening bracket not followed by the closing shortcode tag
+ . '[^\\[]*+' // Not an opening bracket
+ . ')*+'
+ . ')'
+ . '\\[\\/\\2\\]' // Closing shortcode tag
+ . ')?'
+ . ')'
+ . '(\\]?)'; // 6: Optional second closing brocket for escaping shortcodes: [[tag]]
}
/**
* Regular Expression callable for do_shortcode() for calling shortcode hook.
+ * @see get_shortcode_regex for details of the match array contents.
*
* @since 2.5
* @access private
* @param array $m Regular expression match array
* @return mixed False on failure.
*/
-function do_shortcode_tag($m) {
+function do_shortcode_tag( $m ) {
global $shortcode_tags;
- $tag = $m[1];
- $attr = shortcode_parse_atts($m[2]);
+ // allow [[foo]] syntax for escaping a tag
+ if ( $m[1] == '[' && $m[6] == ']' ) {
+ return substr($m[0], 1, -1);
+ }
+
+ $tag = $m[2];
+ $attr = shortcode_parse_atts( $m[3] );
- if ( isset($m[4]) ) {
+ if ( isset( $m[5] ) ) {
// enclosing tag - extra parameter
- return call_user_func($shortcode_tags[$tag], $attr, $m[4]);
+ return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, $m[5], $tag ) . $m[6];
} else {
// self-closing tag
- return call_user_func($shortcode_tags[$tag], $attr);
+ return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, null, $tag ) . $m[6];
}
}
*
* @since 2.5
*
- * @param string $text
+ * @param string $text
* @return array List of attributes and their value.
*/
function shortcode_parse_atts($text) {
$pattern = get_shortcode_regex();
- return preg_replace('/'.$pattern.'/s', '', $content);
+ return preg_replace_callback( "/$pattern/s", 'strip_shortcode_tag', $content );
}
-add_filter('the_content', 'do_shortcode', 11); // AFTER wpautop()
+function strip_shortcode_tag( $m ) {
+ // allow [[foo]] syntax for escaping a tag
+ if ( $m[1] == '[' && $m[6] == ']' ) {
+ return substr($m[0], 1, -1);
+ }
+
+ return $m[1] . $m[6];
+}
-?>
\ No newline at end of file
+add_filter('the_content', 'do_shortcode', 11); // AFTER wpautop()