while($next = (extract_bracketed($text, '{}', '[^{}]*' ))[0]) #this is general.
{ 
    $holder = $next;
    if($bext = (extract_bracketed($next, '{}', '(?s).*?(?=\{ctext|\{code|\{example|\{pre)' ))[0]) #this handles "code" and the like. 
    {
	$bolder = $bext;
	while($cext = (extract_bracketed($bext, '{}', '(?s).*?(?=\{escape)' ))[0])  #this is for escaped "code" and the like.
	{
	    $colder = $cext;
	    $cext =~ s/\{([^ \s|\}]*?)\}/<$1\/>/gix;
	    $cext =~ s/\{([\w|-]*)(.*)\}/<$1>$2<\/$1>/osi;
	    $bext =~ s/$colder/$cext/sgi;
	}
	$bext =~ s/\{pre(.*)\}/\<pre\>$1<\/pre>/gosix;
	$bext =~ s/\{ctext(.*)\}/\<ctext\>$1<\/ctext>/gosix;
	$bext =~ s/\{code(.*)\}/\<code\>$1<\/code>/gosix;
	$bext =~ s/\{example(.*)\}/\<example\>$1<\/example>/gosix;
	$bext =~ s/\}/ebrac/g;
	$bext =~ s/\{/obrac/g;
	$next =~ s/$bolder/$bext/sgi;
    }
$next =~ s/\{([^ \s|\}]*?)\}/<$1\/>/gix;
$next =~ s/\{([\w|-]*)(.*)\}/<$1>$2<\/$1>/osi;
$text =~ s/$holder/$next/sgi;    
}