Chapter 13. The Whole and the Parts
I can call spirits from the vasty deep.Why so can I, or so can any man; but will they come when you do call for them?—SHAKESPEARE, KING HENRY IV, Part I
The modern magic, like the old, has its boastful practitioners: "I can write programs that control air traffic, intercept ballistic missiles, reconcile bank accounts, control production lines." To which the answer comes, "So can I, and so can any man, but do they work when you do write them?"
How does one build a program to work? How does one test a program? And how does one integrate a tested set of component programs into a tested and dependable system? We have touched upon the techniques here and there; let us now consider them somewhat more systematically. ...