I'm wondering why an assignment of the iterator does not cause an infinite loop here?

why_not_infinate.php

<?
/* I know the issue here is the use of the assignment rather then equality, though 
   I would think that this would lead to an infinite loop as $c should be reset to 
   4 for every instance of the $c loop after $r = 2 ... right? But that's not what
   seems to happen? Any one have any insight?

   NOTE: why does the else clause never get tripped, if $c==1?
*/

echo '<pre>';
for($r=0; $r<15; $r++){
  for($c=0; $c<10; $c++){
    if(($r<2) || ($c=4||$c=5) ){
      echo "[$r,$c]";
    }
    else {
      echo '______';                                                                                                                                                                                              
    }
  }
  echo "\n";
}
echo '</pre>';

/*
<pre>[0,0][0,1][0,2][0,3][0,4][0,5][0,6][0,7][0,8][0,9]
[1,0][1,1][1,2][1,3][1,4][1,5][1,6][1,7][1,8][1,9]
[2,1]
[3,1]
[4,1]
[5,1]
[6,1]
[7,1]
[8,1]
[9,1]
[10,1]
[11,1]
[12,1]
[13,1]
[14,1]
</pre>

*/
?>

should ($c=4||$c=5) be using double-equals?

nevermind, see your comment now. looking further.

ah, it's because of operator precedence! it's running the right side as $c = (4 || $c=5) ... or similar. $c ends up being true if you dump just after the conditional check.

wrap parens around ($c=4) and ($c=5) to see the infinite loop