Variable in een variable...

<?php 
$r = "news";
$r_news = "Hannes";
echo $r_$r; //Ik wil dus dat php hier $r_news van maakt, en zodoende Hannes echo'd.
?>

<?php 
$r = "news";
$r_news = "Hannes";
echo $r_$r; //Ik wil dus dat php hier $r_news van maakt, en zodoende Hannes echo'd.
?>

<?php
echo $r_news.$r;

<?php
echo $r_news.$r;

<?php 
$r = "news";
$news = "Hannes";
echo $$r; //Ik wil dus dat php hier $r_news van maakt, en zodoende Hannes echo'd.
?>

<?php 
$r = "news";
$news = "Hannes";
echo $$r; //Ik wil dus dat php hier $r_news van maakt, en zodoende Hannes echo'd.
?>

<?php

 $categorie = "forum";
 $site_['$categorie'] = "website";

 echo $site_['$categorie'];

?>

<?php
 
 $categorie = "forum";
 $site_['$categorie'] = "website";
 
 echo $site_['$categorie'];
 
?>

<?php

 $categorie = "forum";
 $site_[$categorie] = "website";

 echo $site_[$categorie];

?>

<?php
 
 $categorie = "forum";
 $site_[$categorie] = "website";
 
 echo $site_[$categorie];
 
?>

<?php
    echo $r_{$r};

<?php
    echo $r_{$r};

<?php $r = "news"; ?>

<?php $r = "news"; ?>

<?php $r_news = "Hannes"; ?>

<?php $r_news = "Hannes"; ?>