High quality software examples

Question

One of the best ways to learn about programming is reading high quality code/projects from great engineers. Which open-source projects do you think is worth looking at? I mean, that code that you can print and sit under a tree with a glass of wine and enjoy reading.

If you can, also specify if the software is great to look at because its documentation, design, UML diagrams or just plain code. I believe UML is not very common within open-source projects.

Is there such a thing as a project branch that polishes code and design with the sole objective to give other programmers a great example of great software?

Answer 1

At the risk of being perceived as a Jon Skeet fanboy, I've looked to his miscellaneous utilities libraries for examples of clear, self-contained, well-documented and well-tested code. .NET, if it matters.

Answer 2

I'm pretty impressed with the Chrome source code. Note: I work on the Chrome team but I'm just one of many. I've learned quite a bit from other people's code, the classes used, their design, the methods of unit testing, integration testing, their code review system, their continuous build system and more.

Answer 3

Sharp develop is very well designed and written and comes with a book explaining the design.