How to doclare variable smarty

[MathiasReker]

Hello,

 

I have this code in my header.tpl

		<!--Peg start-->
		{if isset($start) && isset($pages_nb)}
	        {if $start != $pages_nb AND $p != 1}
	            {assign var = 'p_previous' value = $p-1 }
	            <link rel="prev" href="{$base_dir_ssl}{$p_req_uri[0]}{$link->goPage($requestPage, $p_previous)}" />
	        {/if}
	        {if $pages_nb > 1 AND $p != $pages_nb}
	            {assign var='p_next' value= $p+1 }
	            <link rel="next" href="{$base_dir_ssl}{$p_req_uri[0]}{$link->goPage($requestPage, $p_next)}" />
	        {/if}
		{/if}
		<!--Peg end-->

It makes rel=next and rel=prev.

 

But I have errors in my log saying that variables is missing, and they are.

 

Undefined index: p_req_uri

Undefined index: requestPage

 

How do I fix this?

Can anyone tell me the code to add into php-file? And where should I add it?