is to manage this complexity by describing in detail the dos and don’ts of writing C++ code. These rules exist to keep the code base manageable while still allowing coders to use C++ language features produc- that underlie all of the individual rules. By bringing these ideas to the fore, we hope to ground discussions and make it clearer to our broader community why the rules are in place and why particular decisions rule in the guide. The goals of the style guide as we currently see them are as follows: 1 Style rules should pull their weight The benefit of a style rule must be large enough to justify asking all of

summaries with the big arrow button: ￿ Toggle all summaries Table of Contents Python Language Rules Lint Imports Packages Exceptions Global variables Nested/Local/Inner Classes and Functions List Comprehensions Features Lexical Scoping Function and Method Decorators Threading Power Features 1 Python Style Rules Semicolons Line length Parentheses Indentation Blank Lines Whitespace Shebang Line Comments Classes Classes Strings Files and Sockets TODO Comments Imports formatting Statements Access Control Naming Main Important Note Displaying Hidden Details in this Guide link￿ This style guide contains many details

Language. A Java source file is described as being in Google Style if and only if it adheres to the rules herein. Like other programming style guides, the issues covered span not only aesthetic issues of conventions or coding standards as well. However, this document focuses primarily on the hard-and-fast rules that we follow universally, and avoids giving advice that isn’t clearly enforceable (whether by human way to represent the code. Optional formatting choices made in examples should not be enforced as rules. 1 2 Source file basics 2.1 File name The source file name consists of the case-sensitive name

R code easier to read, share, and verify. The rules below were designed in collaboration with the entire R user community at Google. Summary: R Style Rules 1. File Names: end in .R 2. Identifiers: variable Function Documentation 14. Example Function 15. TODO Style: TODO(username) Summary: R Language Rules 1. attach: avoid using it 2. Functions: errors should be raised using stop() 3. Objects and Methods: Methods: avoid S4 objects and methods when possible; never mix S3 and S4 1 Notation and Naming File Names File names should end in .R and, of course, be meaningful. GOOD: predict_ad_revenue.R BAD: foo