2003 Prentice Hall, Inc. All rights reserved.

1Dijkstra Letter Quotes• ...the quality of programmers is a

decreasing function of the density of go to statements in the programs they produce.

• ...the go to statement should be abolished from all "higher level" programming languages (i.e. everything except, perhaps, plain machine code).

• we should ... shorten the conceptual gap between the static program and the dynamic process, to make the correspondence between the program (spread out in text space) and the process (spread out in time) as trivial as possible.

• The go to statement as it stands is just too primitive; it is too much an invitation to make a mess of one's program

Go To Statement Considered Harmful, Communications of the ACM, Vol. 11, No. 3, March 1968, pp. 147-148

Edsger W. Dijkstra1930-2002

2003 Prentice Hall, Inc. All rights reserved.

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More Dijkstra Quotes

"Computer Science is no more about computers than astronomy is about telescopes."

"A Programming Language is a tool that has profound influence on our thinking habits."

"The competent programmer is fully aware of the strictly limited size of his own skull; therefore he approaches the programming task in full humility, and among other things he avoids clever tricks like the plague."

"Progress is possible only if we train ourselves to think about programs without thinking of them as pieces of executable code."

"Program testing can best show the presence of errors but never their absence."

2003 Prentice Hall, Inc. All rights reserved.

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Even More Dijkstra Quotes• FORTRAN --"the infantile disorder"--, by now [1975]

nearly 20 years old, is hopelessly inadequate for whatever computer application you have in mind today:it is now too clumsy, too risky, and too expensive to use.

• It is practically impossible to teach good programmingto students that have had a prior exposure to BASIC: as potential programmers they are mentally mutilatedbeyond hope of regeneration.

• With respect to COBOL you can really do only one of two things: fight the disease or pretend that it does not exist. Most Computer Science Departments have opted for the latter easy way out.

Dijkstra Linkshttp://www.cs.utexas.edu/users/EWD/

http://www.kode-fu.com/geek/2002_08_04_archive.shtml

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Deep Thoughts, by Edsger W. Dijkstra

• If debugging is the process of removing bugs...

... then programming must be the process of putting them in.

2003 Prentice Hall, Inc. All rights reserved.

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Deep Thoughts, by Edsger W. Dijkstra

• "I mean, if 10 years from now, when you are doing something quick and dirty, you suddenly visualize that I am looking over your shoulders and say to yourself: 'Dijkstra would not have liked this', well that would be enough immortality for me."

no sir,

I don't like it