htaccess - mod_rewrite "same" rules have to work for both - .htaccess

Question

I really had troubles making a title. So if you have something better, please edit it.
Now to the question:
I'm trying to rewrite some URL's with mod_rewrite in my .htaccess file.
So, what I'm trying to do is to make 2 of the same queries, which of course won't work. Only for one of the rules. So I was thinking if there's some way to tell that if the first rule fails go to the next one? Or - if a rule fails keep looking for another?
Those are my rules which is identical except for the last parameter.
RewriteRule ^udforsk/([a-z-]+)/([0-9]+)$ index.php?page=udforsk&q=1&s=$1&val=$2
RewriteRule ^udforsk/([a-z-]+)/([0-9]+)$ index.php?page=udforsk&q=1&s=$1&p=$2

Answer 1

Correct me if I'm wrong but, if you are passing the arguments in via GET, then index.php should handle the error that would happen if it were missing a GET variable.
In index.php, treat $_GET["p"] like you would treat $_GET["val"], actually, why not use isset() and set p equal to val (if p isn't already set)

Answer 2

The rewrite won't check to see if the page you are calling in your rule is actually valid. It will just try to serve it up and then because you don't have [L] it will try to serve up the next one too.
What you should probably do is change your first URL to pass that $2 value as two different parameters
RewriteRule ^udforsk/([a-z-]+)/([0-9]+)$ index.php?page=udforsk&q=1&s=$1&val=$2
RewriteRule ^udforsk/([a-z-]+)/([0-9]+)$ index.php?page=udforsk&q=1&s=$1&p=$2
should be
RewriteRule ^udforsk/([a-z-]+)/([0-9]+)$ index.php?page=udforsk&q=1&s=$1&val=$2&p=$2
Then let your index.php do the work of picking which parm to use "val" or "p" based on logic in the php script.
For sure in your php code use "isset" to test for the variable.
$value = (isset($_REQUEST["val"]) ? $_REQUEST["val"] : (isset($_REQUEST["p"]) ? $_REQUEST["p"] : "error"));
$value will hold the contents of "val" or "p" or the word "error" if neither of the others are set.