CSC/ECE 517 Fall 2007/wiki3 10 tm

"The Agile debate. Perhaps the most prominent controversy in o-o design today is whether it is possible to do a robust design with as little advance planning as agile methodologies recommend. Research this issue, on the Web and in the ACM DL, and report (fairly) on the major arguments of both sides, and on the evidence for both positions.

What is 'Agile Methodologies'?

'Principle of Least Astonishment' or 'Rule of minimum surprise' asserts that the system will cause the least surprise for the user by being as consistent and predictable as possible, and therefore usable. Which imply that in case of an ambiguity or a conflict in the system, the behavior of the system should be the one which will least surprise the user. In computer science, this principle has a wide range of application in topics such as user-interface design, programming language design, and programming. This principle is used in various disciplines as well as computer science such as engineering, science, and philosophy which are covered later in this wiki. After this brief information about the principle of least astonishment, now we are going to talk more about the sources found online about this topic and how well they explore the topic.

Argument *Against* Agile Methodologies

"Principle of Least Astonishment at Portland Pattern Repository" provides a simple explanation to the topic and gives a couple of easy-to-understand examples; this is one of the best sites that one should start to learn on this topic.

Argument *With* Agile Methodologies

"Ethical Software" is a blog of an instructor, Alex Bunardzic, where he shares his in class experience when he was teaching Principle of Least Astonishment. The example that he gave in class is the Ruby on Rails code where he suggests using <%yield%> instead of <%content_for_layout%> to demonstrate this principle. This web page is not a good start to learn the topic, but it gives the idea of the principle and it demonstrates it with the Ruby on Rails code which is very related to what we have been doing in our class.

Success Stories

"Site finding system" is a topic appeared in BBC News on September, 2003 which gives an real-life example of violation of this principle, and explains what it had caused.

Agile Methodologies in Other Disciplines

• "Quran" Quran provides many arguments based upon 'Least Astonishment' and 'Occam's razor' principles for several controversies as creation/evolution controversy, existence of god, miracles. From the author point of view, Quran also obey the same rules of nature, which suggest it is from the same creator.

Conclusion

This wiki is intended to be a Guide for Principle of Least Astonishment. It provides many links to online sources that explains the topic simply with easy-to-understand examples, and/or gives an idea where this principle can be used in real-life. These links should be helpful for the ones who want to learn more on this topic or understand the topic in more detail.

This principle can be used in many different disciplines for a universal useful solution for good designs. But it should be taken into consideration that the principle goes parallel with common sense, although it may not go with the convention.

From "The Incomplete Guide to the Art of Discovery", *.PDF

External Links by Side

Against

• "Applying the Rule of Least Surprise" from The Art of Unix Programming by E.S. Raymond
• "Wikipedia"
• "Confessions of a Coder"

With

• "Site finding system faces suspension"
• "Applying the Rule of Least Surprise in webpages"

External Links by Methodology

XP

• "Applying the Rule of Least Surprise in webpages"