diff --git a/Readme.md b/Readme.md index 2404883..52ece4f 100644 --- a/Readme.md +++ b/Readme.md @@ -17,6 +17,7 @@ according to your preferences. ## Table of contents +### Formatting * [2 Spaces for indention](#2-spaces-for-indention) * [Newlines](#newlines) * [No trailing whitespace](#no-trailing-whitespace) @@ -24,42 +25,55 @@ according to your preferences. * [80 characters per line](#80-characters-per-line) * [Use single quotes](#use-single-quotes) * [Opening braces go on the same line](#opening-braces-go-on-the-same-line) -* [Method chaining](#method-chaining) * [Declare one variable per var statement](#declare-one-variable-per-var-statement) + +### Naming Conventions * [Use lowerCamelCase for variables, properties and function names](#use-lowercamelcase-for-variables-properties-and-function-names) * [Use UpperCamelCase for class names](#use-uppercamelcase-for-class-names) * [Use UPPERCASE for Constants](#use-uppercase-for-constants) + +### Variables * [Object / Array creation](#object--array-creation) + +### Conditionals * [Use the === operator](#use-the--operator) * [Use multi-line ternary operator](#use-multi-line-ternary-operator) -* [Do not extend built-in prototypes](#do-not-extend-built-in-prototypes) * [Use descriptive conditions](#use-descriptive-conditions) + +### Functions * [Write small functions](#write-small-functions) * [Return early from functions](#return-early-from-functions) * [Name your closures](#name-your-closures) * [No nested closures](#no-nested-closures) +* [Method chaining](#method-chaining) + +### Comments * [Use slashes for comments](#use-slashes-for-comments) + +### Miscellaneous * [Object.freeze, Object.preventExtensions, Object.seal, with, eval](#objectfreeze-objectpreventextensions-objectseal-with-eval) * [Getters and setters](#getters-and-setters) +* [Do not extend built-in prototypes](#do-not-extend-built-in-prototypes) +## Formatting -## 2 Spaces for indention +### 2 Spaces for indention Use 2 spaces for indenting your code and swear an oath to never mix tabs and spaces - a special kind of hell is awaiting you otherwise. -## Newlines +### Newlines Use UNIX-style newlines (`\n`), and a newline character as the last character of a file. Windows-style newlines (`\r\n`) are forbidden inside any repository. -## No trailing whitespace +### No trailing whitespace Just like you brush your teeth after every meal, you clean up any trailing whitespace in your JS files before committing. Otherwise the rotten smell of careless neglect will eventually drive away contributors and/or co-workers. -## Use Semicolons +### Use Semicolons According to [scientific research][hnsemicolons], the usage of semicolons is a core value of our community. Consider the points of [the opposition][], but @@ -69,13 +83,13 @@ cheap syntactic pleasures. [the opposition]: http://blog.izs.me/post/2353458699/an-open-letter-to-javascript-leaders-regarding [hnsemicolons]: http://news.ycombinator.com/item?id=1547647 -## 80 characters per line +### 80 characters per line Limit your lines to 80 characters. Yes, screens have gotten much bigger over the last few years, but your brain has not. Use the additional room for split screen, your editor supports that, right? -## Use single quotes +### Use single quotes Use single quotes, unless you are writing JSON. @@ -91,7 +105,7 @@ var foo = 'bar'; var foo = "bar"; ``` -## Opening braces go on the same line +### Opening braces go on the same line Your opening braces go on the same line as the statement. @@ -114,51 +128,7 @@ if (true) Also, notice the use of whitespace before and after the condition statement. -## Method chaining - -One method per line should be used if you want to chain methods. - -You should also indent these methods so it's easier to tell they are part of the same chain. - -*Right:* - -```js -User - .findOne({ name: 'foo' }) - .populate('bar') - .exec(function(err, user) { - return true; - }); -```` - -*Wrong:* - -```js -User -.findOne({ name: 'foo' }) -.populate('bar') -.exec(function(err, user) { - return true; -}); - -User.findOne({ name: 'foo' }) - .populate('bar') - .exec(function(err, user) { - return true; - }); - -User.findOne({ name: 'foo' }).populate('bar') -.exec(function(err, user) { - return true; -}); - -User.findOne({ name: 'foo' }).populate('bar') - .exec(function(err, user) { - return true; - }); -```` - -## Declare one variable per var statement +### Declare one variable per var statement Declare one variable per var statement, it makes it easier to re-order the lines. However, ignore [Crockford][crockfordconvention] when it comes to @@ -194,7 +164,9 @@ while (keys.length) { [crockfordconvention]: http://javascript.crockford.com/code.html -## Use lowerCamelCase for variables, properties and function names +### Naming Conventions + +### Use lowerCamelCase for variables, properties and function names Variables, properties and function names should use `lowerCamelCase`. They should also be descriptive. Single character variables and uncommon @@ -212,7 +184,7 @@ var adminUser = db.query('SELECT * FROM users ...'); var admin_user = db.query('SELECT * FROM users ...'); ``` -## Use UpperCamelCase for class names +### Use UpperCamelCase for class names Class names should be capitalized using `UpperCamelCase`. @@ -261,7 +233,9 @@ File.fullPermissions = 0777; [const]: https://developer.mozilla.org/en/JavaScript/Reference/Statements/const -## Object / Array creation +## Variables + +### Object / Array creation Use trailing commas and put *short* declarations on a single line. Only quote keys when your interpreter complains: @@ -287,7 +261,9 @@ var b = {"good": 'code' }; ``` -## Use the === operator +## Conditionals + +### Use the === operator Programming is not about remembering [stupid rules][comparisonoperators]. Use the triple equality operator as it will work just as expected. @@ -313,7 +289,7 @@ if (a == '') { [comparisonoperators]: https://developer.mozilla.org/en/JavaScript/Reference/Operators/Comparison_Operators -## Use multi-line ternary operator +### Use multi-line ternary operator The ternary operator should not be used on a single line. Split it up into multiple lines instead. @@ -331,34 +307,7 @@ var foo = (a === b) var foo = (a === b) ? 1 : 2; ``` -## Do not extend built-in prototypes - -Do not extend the prototype of native JavaScript objects. Your future self will -be forever grateful. - -*Right:* - -```js -var a = []; -if (!a.length) { - console.log('winning'); -} -``` - -*Wrong:* - -```js -Array.prototype.empty = function() { - return !this.length; -} - -var a = []; -if (a.empty()) { - console.log('losing'); -} -``` - -## Use descriptive conditions +### Use descriptive conditions Any non-trivial conditions should be assigned to a descriptively named variable or function: @@ -380,13 +329,15 @@ if (password.length >= 4 && /^(?=.*\d).{4,}$/.test(password)) { } ``` -## Write small functions +## Functions + +### Write small functions Keep your functions short. A good function fits on a slide that the people in the last row of a big room can comfortably read. So don't count on them having perfect vision and limit yourself to ~15 lines of code per function. -## Return early from functions +### Return early from functions To avoid deep nesting of if-statements, always return a function's value as early as possible. @@ -433,7 +384,7 @@ function isPercentage(val) { } ``` -## Name your closures +### Name your closures Feel free to give your closures a name. It shows that you care about them, and will produce better stack traces, heap and cpu profiles. @@ -454,7 +405,7 @@ req.on('end', function() { }); ``` -## No nested closures +### No nested closures Use closures, but don't nest them. Otherwise your code will become a mess. @@ -480,7 +431,54 @@ setTimeout(function() { }, 1000); ``` -## Use slashes for comments + +### Method chaining + +One method per line should be used if you want to chain methods. + +You should also indent these methods so it's easier to tell they are part of the same chain. + +*Right:* + +```js +User + .findOne({ name: 'foo' }) + .populate('bar') + .exec(function(err, user) { + return true; + }); +```` + +*Wrong:* + +```js +User +.findOne({ name: 'foo' }) +.populate('bar') +.exec(function(err, user) { + return true; +}); + +User.findOne({ name: 'foo' }) + .populate('bar') + .exec(function(err, user) { + return true; + }); + +User.findOne({ name: 'foo' }).populate('bar') +.exec(function(err, user) { + return true; +}); + +User.findOne({ name: 'foo' }).populate('bar') + .exec(function(err, user) { + return true; + }); +```` + +## Comments + +### Use slashes for comments Use slashes for both single line and multi line comments. Try to write comments that explain higher level mechanisms or clarify difficult @@ -524,11 +522,13 @@ if (isSessionValid) { } ``` -## Object.freeze, Object.preventExtensions, Object.seal, with, eval +## Miscellaneous + +### Object.freeze, Object.preventExtensions, Object.seal, with, eval Crazy shit that you will probably never need. Stay away from it. -## Getters and setters +### Getters and setters Do not use setters, they cause more problems for people who try to use your software than they can solve. @@ -537,3 +537,30 @@ Feel free to use getters that are free from [side effects][sideeffect], like providing a length property for a collection class. [sideeffect]: http://en.wikipedia.org/wiki/Side_effect_(computer_science) + +### Do not extend built-in prototypes + +Do not extend the prototype of native JavaScript objects. Your future self will +be forever grateful. + +*Right:* + +```js +var a = []; +if (!a.length) { + console.log('winning'); +} +``` + +*Wrong:* + +```js +Array.prototype.empty = function() { + return !this.length; +} + +var a = []; +if (a.empty()) { + console.log('losing'); +} +```