Nick Bartlett

I found the following code today that reminded me of my first attempt at programming in college. I was having a terrible time with it and was convinced I did not want to do programming as a career. Unfortunately, the code I’d written was based off an example in a book, which looked very much like the below code I found today while at work.

function calculate_easter($y) {
	$a = $y % 19;
	$b = intval($y / 100);
	$c = $y % 100;
	$d = intval($b / 4);
	$e = $b % 4;
	$f = intval(($b + 8) / 25);
	$g = intval(($b - $f + 1) / 3);
	$h = (19 * $a + $b - $d - $g + 15) % 30;
	$i = intval($c / 4);
	$k = $c % 4;
	$l = (32 + 2 * $e + 2 * $i - $h - $k) % 7;
	$m = intval(($a + 11 * $h + 22 * $l) / 451);
	$p = ($h + $l - 7 * $m + 114) % 31;
	$EasterMonth = intval(($h + $l - 7 * $m + 114) / 31); // [3 = March, 4 = April]
	$EasterDay = $p + 1; // (day in Easter Month)
	return format_date($y, $EasterMonth, $EasterDay);
}

I can’t make heads or tails of this code and leaves me thinking the person who wrote it was either very smart or very dumb. I’d lean towards the latter.

When I asked my professor for help and showed him my program full of single letter variable names, he said “have you ever heard of meaningful identifiers?”. He should have given me a smack on the head as he said it. Today, I don’t mind writing out long variable names or functions names as long as they “meaningfully” describe the variable or function. Trust me on this – it will make code maintenance much easier in the long run and will make the lives of other developers looking at your code much less painful.

A side note – the author of the above code could have just used PHP’s built in easter_date function http://us2.php.net/easter_date .