Let’s say that power means “the amount of work done per unit of time.”

It could be said that development is made up of these types of work (and much more):

• Design
• Prototyping
• Learning the Language
• Writing New Code
• Understanding Old Code
• Refactoring
• Debugging New Code
• Debugging Old Code
• Reading Other People’s Code
• Debugging Other People’s Code
• Making Use of Libraries
• Making Libraries
• Refactoring Libraries
• Updating to Refactored Libraries

JavaScript, Python, and dynamic languages in general do well in some of these areas but not others

For example, “Writing New Code” seems to be the area of focus for advocates of dynamic languages, who see a big power gain there, and possibly in “Learning the Language”.

It seems to me, however, that Java is just as powerful as dynamic languages in the other categories, and much more powerful if you use an IDE with support for completion and refactoring.

That is to say, I can get a hell of a lot more refactoring done per unit of time in Java using Eclipse than I’ve seen in any other language.

This post was inspired this other blog post that compares using GWT to Javascript: http://blogs.pathf.com/agileajax/2007/05/angry_at_gwt.html