Google Code Search was a free

beta Beta (, ; uppercase , lowercase , or cursive ; grc, βῆτα, bē̂ta or ell, βήτα, víta) is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Modern Greek, it represents the voiced labiod ...

product from

Google Google LLC () is an American multinational technology company focusing on search engine technology, online advertising, cloud computing, computer software, quantum computing, e-commerce, artificial intelligence, and consumer electronics. ...

which debuted in

Google Labs Google Labs was an incubator created by Google to test and publicly demonstrate new projects. It was online from early 2002 to mid-2011. Google described Google Labs as "a playground where our more adventurous users can play around with prototyp ...

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 Subversion () refers to a process by which the values and principles of a system in place are contradicted or reversed in an attempt to transform the established social order and its structures of power, authority, hierarchy, and social norms. Sub ...

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" or ...

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 sam ...

, but over the world's public code. The methodology employed, sometimes called

trigram search Trigram search is a method of searching for text when the exact syntax or spelling of the target object is not precisely known or when queries may be regular expressions. It finds objects which match the maximum number of three consecutive character ...

, 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 Context is ...

index Index (or its plural form indices) may refer to: Arts, entertainment, and media Fictional entities * Index (''A Certain Magical Index''), a character in the light novel series ''A Certain Magical Index'' * The Index, an item on a Halo megastru ...

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 connect ...

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 Russ is a masculine given name, often a short form of Russell, and also a surname. People Given name or nickname * Russ Abbot (born 1947), British musician, comedian and actor * Russ Adams (born 1980), American retired baseball player * Russ B ...

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 Chromium is a chemical element with the symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal. Chromium metal is valued for its high corrosion resistance and hardne ...

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