_MarkdownExtra_TmpImpl::stripFootnotes PHP Method

    protected function stripFootnotes($text)
    {
        #
        # Strips link definitions from text, stores the URLs and titles in
        # hash references.
        #
        $less_than_tab = $this->tab_width - 1;
        # Link defs are in the form: [^id]: url "optional title"
        $text = preg_replace_callback('{
			^[ ]{0,' . $less_than_tab . '}\\[\\^(.+?)\\][ ]?:	# note_id = $1
			  [ ]*
			  \\n?					# maybe *one* newline
			(						# text = $2 (no blank lines allowed)
				(?:					
					.+				# actual text
				|
					\\n				# newlines but 
					(?!\\[.+?\\][ ]?:\\s)# negative lookahead for footnote or link definition marker.
					(?!\\n+[ ]{0,3}\\S)# ensure line is not blank and followed 
									# by non-indented content
				)*
			)		
			}xm', array($this, '_stripFootnotes_callback'), $text);
        return $text;
    }