Array key problem

["Jorge Miguel Fonseca Martins" <jorge.martins@wemake.pt>]

Hi! Anyone got an idea what the problem may be with the following code
 
 $test[]="a";
 $test[]="b";
 
 foreach ($test as $key=>$value)
 {
  if($key == "something") echo $key
 }
 
even though theres no key in the array named "something" the code will
print the key "0"
 
Thanks