Friday, August 1, 2008

Für Dad und Aileen

I was reclined at the Santos' house, doing what I alway do, besides eating, playing with the kids and sleeping: reading. In this case I was reading one of Aileen's books: 101 Puzzles in Thought and Logic by a C.R. Wylie, Jr. I enjoyed solving the simple problems in my head, and wondered how I would go about programming a computer to solve these kinds of puzzles (that was the real endeavor). Seeing as the book was published in 1957, I asked Mike (Wuerthele, so this entry is für him, too) if I could borrow the book.

"'Sure'" he responded, straightfacedly. ... The movie's title was The Pink Panther Strikes Again, btw.

So, after obtaining real permission for the rightful owner, Aileen, I disappeared into the bowels of my office to solve problem 1:

In a certain bank the positions of cashier, manager, and teller are held by Brown, Jones and Smith, though not necessarily respectively.

The teller, who was an only child, earns the least.
Smith, who married Brown's sister, earns more than the manager.

What position does each man fill?


Obvious solution, right? Well, to get the computer to solve it, I needed to invent an entirely new data type in my current language of choice, Haskell. So, it's all because of Aileen that the world is now a better place: Haskell is one step closer to simulating the full predicate calculus syntactically. So that's why this entry is für her (in the same fashion that Ole Abe credited Ms. Stowe).

Well, of course, if you FOLLOW THE LINK (c'mon, you can do it, it's just one click of your mouse ... doit-doit-doit), you'll discover that the data type is the (monadic) dual to the Maybe data type: it's called the Whatever data type. And that is why this post is for my father: he's a passionate and caring man -- the insipidness of the word "whatever" always goes against his grain. But here I show this word has firm mathematical underpinnings and captures the essence of a valid addition to the logic programming paradigm in Haskell. I'm sure his eruditious bones will be well-pleased with the development, however, and that's why this post is für him.

I don't happen to know any Elises, but if I did, LvB might have some choice words for me if I made this post für her, so, I won't.

1 comment:

Eve said...

I followed the links.
And came across the Monad.

I tried to follow the Monad.
It's over my head.

Have no Mensa head.
But know someone who has.