That's pretty intense...
I only assumed it does. I thought create_function returns a reference to the anonymous function, just as a function name is a reference to a named function.
$newfunc = create_function('$a,$b', 'return "ln($a) + ln($b) = " . log($a * $b);');
echo $newfunc(2, M_E);
Is equivilent to:
function newfunc ($a,$b) { return "ln($a) + ln($b) = " . log($a * $b); }
echo $newfunc(2, M_E);