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[Technical Note] Taking liberties with program notation

These ``programs'' are really program fragments. They use ``Pascal notation'' in the sense that the form of assignment commands and for-loop headers, and the basic functions ord and chr, are taken from Pascal. I left out the program headers and the semicolons, and I delimited the body of the for-loop by indentation rather than begin and end. In order to discuss programming language issues efficiently, it is crucial that we learn to focus attention on the essential relevant points, and ignore the others. This is hard, because the ``essential relevant'' points will be totally different, depending on the concept that we are studying.

Notice that my presentation of these two solutions to the vowel-printing problem is absolutely precise in its essentials. The things that are left out can only be filled in one obvious way. Now is the time to start distinguishing between economical presentation and sloppy presentation that leaves out crucial information. The former is necessary for clarity, the latter is unacceptable.


Michael J. O'Donnell <odonnell@cs.uchicago.edu>
Last modified: Thu Sep 23 16:48:39 CDT 1999