"A Programmer's Night Before Christmas" joke

Twas the night before Christmas, and all through the shop,
The computers were whirring; they never do stop.
The power was on and the temperature right,
In hopes that the input would feed back that night.
The system was ready, the program was coded,
And memory drums had been carefully loaded;
While adding a Christmasy glow to the scene,
The lights on the console, flashed red, white and green.
When out in the hall there arose such a clatter,
The programmer ran to see what was the matter.
Away to the hallway he flew like a flash,
Forgetting his key in his curious dash.
He stood in the hallway and looked all about,
When the door slammed behind him, and he was locked out.
Then, in the computer room what should appear,
But a miniature sleigh and eight tiny reindeer;
And a little old man, who with scarcely a pause,
Chuckled: "My name is Santa... the last name is Claus."
The computer was startled, confused by the name,
Then it buzzed as it heard the old fellow exclaim:
"This is Dasher and Dancer and Prancer and Vixen,
And Comet and Cupid and Donner and Blitzen."
With all these odd names, it was puzzled anew;
It hummed and it clanked, and a main circuit blew.
It searched in its memory core, trying to "think";
Then the multi-line printer went out on the blink.
Unable to do its electronic job,
It said in a voice that was almost a sob:
"Your eyes - how they twinkle - your dimples so merry,
Your cheeks so like roses, your nose like a cherry,
Your smile - all these things, I've been programmed to know,
And at data-recall, I am more than so-so;
But your name and your address (computers can't lie),
Are things that I just cannot identify.
You've a jolly old face and a little round belly,
That shakes when you laugh like a bowl full of jelly;
My scanners can see you, but still I insist,
Since you're not in my program, you cannot exist!"
Old Santa just chuckled a merry "ho, ho",
And sat down to type out a quick word or so.
The keyboard clack-clattered, its sound sharp and clean,
As Santa fed this "data" to the machine:
"Kids everywhere know me; I come every year;
The presents I bring add to everyone's cheer;
But you won't get anything - that's plain to see;
Too bad your programmers forgot about me."
Then he faced the machine and said with a shrug,
"Merry Christmas to All," as he pulled out its plug!