Google just launched a
new search service which allows you to search open source code. Search prefixes like license: and lang: can narrow results and the search supports POSIX regular expression syntax. The results are displayed as a link to the source code, a clip of the code and a link to a zip file which contains the entire code package.
While a nice new feature and one that will no doubt be handy for web developers, it seems to me that most people looking for source code might really be looking for something more like a tutorial. Of course as they say, good code is self documenting, so perhaps this will inspire programmers to write cleaner code and clearer documentation. Probably not, but we can always dream can't we?
It's worth noting that Google acknowledges in their FAQ that, while they try to "determine the software license for code packages by looking for a license in the comments or in a separate license file," the results are, as they put it, "not perfect." In other words, just because Code Search thinks a file is licensed under the GPL doesn't mean that it is and presumably it's up to you to verify the license before using the code.
If you'd like to make sure that your code is not indexed by Google, there are instructions for doing so in the
Code Search FAQ.
Oh and speaking of not perfect, Google appears to have turned off their spellchecker this morning which leaves us to search for a "regular expresion [sic]." Or perhaps this is their subtle way of letting us know that Google is still powered by humans.