Clippings

As Gregor Samsa awoke one morning from uneasy dreams he found himself transformed in his bed into a gigantic insect. He was lying on his hard, as it were armor-plated, back and when he lifted his head a little he could see his dome-like brown belly divided into stiff arched segments on top of which the bed quilt could hardly keep in position and was about to slide off completely. His numerous legs, which were pitifully thin compared to the rest of his bulk, waved helplessly before his eyes.

There are two basic styles for expressing functions, the pointwise style and the point-free style. In the pointwise style we describe a function by describing its application to arguments. … In the point-free style we describe a function exclusively in terms of functional composition. …we want to illustrate … how a point-free style leads to a very simple method for reasoning about functions.