can't  work a script
  $r=0;
  if ($r=1) {$a=1;} //comparison on equal
  else {$a=0;}
  print "Result=$a"; 
i see always "Result=1" 
but can work a script
  $r=0;
  if ($r==1) {$a=1;} //comparison on identical
  else {$a=0;}
  print "Result=$a";
i did see manual of PHP what must work both ways