Google crawls into source code search

Search giant gives software developers a tool that lets them search billions of lines of source code.

Google is taking its search expertise to one of its favorite audiences: software developers.

The company on Thursday launched a Web site, Google Code Search, which the company says will let programmers search billions of lines of code for tips on how to write their own software.

The service, conceived by the Google Labs early technology group, will crawl publicly available code, most of which is made available through open-source projects. The search and indexing covers code on Web pages and code that resides in compressed files, said Tom Stocky, a product manager at Google.

Google expects that the search engine will be used primarily as a learning tool to help students and serious programmers, rather than a way to find and copy another person's code.

"Most of the code is open source so you can reuse it. But I don't think that's the primary use--it's more about how to learn about things and, when you're building open-source packages, to make sure you doing it the right way," Stocky said.

For example, a developer may need to write a function as part of an application and search the Web to see other examples.

Google engineers, many of whom participate in open-source projects, already use these code-searching capabilities internally. Since it is a Google Labs project, the company is not yet seeking to make money through ads linked to searches, Stocky said.

The search engine will let people do both keyword search and "regular expressions," which allow people to search a specified pattern, he said. For example, a person could narrow a search to JavaScript functions, which will help find more examples, Stocky said.

As it does with many of its services, Google will release an application programming interface (API) to create an XML feed based on a specific query.

Although it doesn't sell programming tools, Google has an active developer-outreach program and relies on third-party programmers to enhance its services.

For example, developers have created popular mashup applications that display information from a Web site, such a real-estate listings site, using Google Maps.

"More and more (the developer community) is the way Google products are getting to scale," Stocky said. "We think developers can really improve Google products and use Google technology to improve their own products."

Featured Video