Summary
As debuggers have grown in power and capability, they have become more and more harmful to the process of software development.

Debuggers have become immensely powerful. A good debugger is a very capable tool. With it, an experienced developer can step through very complex code, look at all the variables, data structures, and stack frames; even modify the code and continue. And yet, for all their power, debuggers have done more to damage software development than help it.

Since I started using Test Driven Development in 1999, I have not found a serious use for a debugger. The kinds of bugs I have to troubleshoot are easily isolated by my unit tests, and can be quickly found through inspection and a few judiciously placed print statements.

I teach a lot of classes in C++, Java, C#, TDD, XP, Patterns, etc. In those classes I often have the students write code. It is not unusual for me to find a student with his or her nose buried in a debugger, painstakingly stepping from line to line, examining variables, setting breakpoints, and generally wasting time. The bug they are tracking could be found through simple inspection of the code.

I consider debuggers to be a drug -- an addiction. Programmers can get into the horrible habbit of depending on the debugger instead of on their brain. IMHO a debugger is a tool of last resort. Once you have exhausted every other avenue of diagnosis, and have given very careful thought to just rewriting the offending code, *then* you may need a debugger.

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About the Blogger

Robert C. Martin (Uncle Bob) has been a software professional since 1970 and an international software consultant since 1990. He is founder and president of Object Mentor Inc., a team of experienced consultants who mentor their clients worldwide in the fields of C++, Java, OO, Patterns, UML, Agile Methodologies, and Extreme Programming. In 1995 Robert authored the best-selling book: Designing Object Oriented C++ Applications using the Booch Method, published by Prentice Hall. From 1996 to 1999 he was the editor-in-chief of the C++ Report. In 1997 he was chief editor of the book: Pattern Languages of Program Design 3, published by Addison Wesley. In 1999 he was the editor of "More C++ Gems" published by Cambridge Press. He is co-author, with James Newkirk, of "XP in Practice", Addision Wesley, 2001. In 2002 he wrote the long awaited "Agile Software Development: Principles, Patterns, and Practices", Prentice Hall, 2002. He has published many dozens of articles in various trade journals, and is a regular speaker at international conferences and trade shows.