Child of <file>. Value can be a language name or "archive". Examples for the language name include: "C", "Python", "C#", "Java", "Vim".
Case is ignored; "Java", "JAVA" and "java" are equivalent.
The value must be printable ASCII characters, no white space.
The name must be one of the supported languages.
We only index files with a supported language. All other files will be ignored. You can use a language name that we do not support yet, and we may index the file in the future.
The special value "archive" can be used for an archive inside an archive. This is only useful if this archive contains source code.
Because Code Search indexes only source code, there is no need to add an entry for any archive containing only text, html, etc.