Google Code Search was a free beta product from

Google Google LLC () is an American Multinational corporation, multinational technology company focusing on Search Engine, search engine technology, online advertising, cloud computing, software, computer software, quantum computing, e-commerce, ar ...

which debuted in Google Labs on October 5, 2006, allowing web users to search for open-source code on the Internet. Features included the ability to search using operators, namely , , , and . The code available for searching was in various formats including tar.gz, .tar.bz2, .tar, and .zip, CVS, Subversion,

git Git () is a distributed version control system: tracking changes in any set of files, usually used for coordinating work among programmers collaboratively developing source code during software development. Its goals include speed, data in ...

and

Mercurial Mercurial is a distributed revision control tool for software developers. It is supported on Microsoft Windows and Unix-like systems, such as FreeBSD, macOS, and Linux. Mercurial's major design goals include high performance and scalability, d ...

repositories. Google Code Search covered many open-source projects, and as such is different from the "Code Search for Google Open source projects" that was released afterwards.

Regular expression engine

The site allowed the use of

regular expression A regular expression (shortened as regex or regexp; sometimes referred to as rational expression) is a sequence of characters that specifies a search pattern in text. Usually such patterns are used by string-searching algorithms for "find" ...

s in queries, which at that time was not offered by any other search engine for code. This makes it resemble

grep grep is a command-line utility for searching plain-text data sets for lines that match a regular expression. Its name comes from the ed command ''g/re/p'' (''globally search for a regular expression and print matching lines''), which has the sa ...

, but over the world's public code. The methodology employed, sometimes called trigram search, combines a

trigram Trigrams are a special case of the ''n''-gram, where ''n'' is 3. They are often used in natural language processing for performing statistical analysis of texts and in cryptography for control and use of ciphers and codes. Frequency Contex ...

index with a custom-built,

denial-of-service In computing, a denial-of-service attack (DoS attack) is a cyber-attack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host conne ...

resistant

engine. In March 2010, the code of RE2, the regular expression engine used in Google Code Search, was made open source. Google Code Search supported POSIX extended regular expression syntax, excluding back-references, collating elements, and collation classes. Languages not officially supported could be searched for using the file: operator to match the common file extensions for the language.

Discontinuation

In October 2011, Google announced that Code Search was to be shut down along with the Code Search API. The service remained online until March 2013, and it now returns a 404. In January 2012, Russ Cox published an overview of history and the technical aspects of the tool, and open-sourced a basic implementation of a similar functionality as a set of standalone programs that can run fast indexed regular expression searches over local code.

References

External links

*
Cindex/Csearch
- command-line file search tool, based on ideas from GCS
Version of Code Search
limited to the Chromium project
android source code search

chrome source code search
{{Google Inc. Code search engines Defunct internet search engines Code Search

Regular expression engine

Discontinuation

See also

References

External links