Angieslist-javascript-styleguide NPM

Angie's List JavaScript Style Guide() {

Based off of AirBnB's style guide.

A mostly reasonable approach to JavaScript

Other Style Guides

React

Types

1.1 Primitives: When you access a primitive type you work directly on its value.
- string
- number
- boolean
- null
- undefined
```
const foo = 1;
let bar = foo;

bar = 9;

console.log(foo, bar); // => 1, 9
```
1.2 Complex: When you access a complex type you work on a reference to its value.
- object
- array
- function
```
const foo = [1, 2];
const bar = foo;

bar[0] = 9;

console.log(foo[0], bar[0]); // => 9, 9
```

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References

2.1 Use const for all of your references; avoid using var. eslint: prefer-const, no-const-assign
Why? This ensures that you can't reassign your references, which can lead to bugs and difficult to comprehend code.
```
// bad
var a = 1;
var b = 2;

// good
const a = 1;
const b = 2;
```
2.2 If you must reassign references, use let instead of var. eslint: no-var jscs: disallowVar
Why? let is block-scoped rather than function-scoped like var.
```
// bad
var count = 1;
if (true) {
  count += 1;
}

// good, use the let.
let count = 1;
if (true) {
  count += 1;
}
```

2.3 Note that both let and const are block-scoped.

// const and let only exist in the blocks they are defined in.
{
  let a = 1;
  const b = 1;
}
console.log(a); // ReferenceError
console.log(b); // ReferenceError

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Objects

3.1 Use the literal syntax for object creation. eslint: no-new-object
```
// bad
const item = new Object();

// good
const item = {};
```
3.2 If your code will be executed in browsers in script context, don't use reserved words as keys. It won't work in IE8. More info. It’s OK to use them in ES6 modules and server-side code. jscs: disallowIdentifierNames
```
// bad
const superman = {
  default: { clark: 'kent' },
  private: true,
};

// good
const superman = {
  defaults: { clark: 'kent' },
  hidden: true,
};
```

3.3 Use readable synonyms in place of reserved words. jscs: disallowIdentifierNames

// bad
const superman = {
  class: 'alien',
};

// bad
const superman = {
  klass: 'alien',
};

// good
const superman = {
  type: 'alien',
};

3.4 Use computed property names when creating objects with dynamic property names.

Why? They allow you to define all the properties of an object in one place.

function getKey(k) {
  return `a key named ${k}`;
}

// bad
const obj = {
  id: 5,
  name: 'San Francisco',
};
obj[getKey('enabled')] = true;

// good
const obj = {
  id: 5,
  name: 'San Francisco',
  [getKey('enabled')]: true,
};

3.5 Use object method shorthand. eslint: object-shorthand jscs: requireEnhancedObjectLiterals

// bad
const atom = {
  value: 1,

  addValue: function (value) {
    return atom.value + value;
  },
};

// good
const atom = {
  value: 1,

  addValue(value) {
    return atom.value + value;
  },
};

3.6 Use property value shorthand. eslint: object-shorthand jscs: requireEnhancedObjectLiterals

Why? It is shorter to write and descriptive.

const lukeSkywalker = 'Luke Skywalker';

// bad
const obj = {
  lukeSkywalker: lukeSkywalker,
};

// good
const obj = {
  lukeSkywalker,
};

3.7 Group your shorthand properties at the beginning of your object declaration.

Why? It's easier to tell which properties are using the shorthand.

const anakinSkywalker = 'Anakin Skywalker';
const lukeSkywalker = 'Luke Skywalker';

// bad
const obj = {
  episodeOne: 1,
  twoJediWalkIntoACantina: 2,
  lukeSkywalker,
  episodeThree: 3,
  mayTheFourth: 4,
  anakinSkywalker,
};

// good
const obj = {
  lukeSkywalker,
  anakinSkywalker,
  episodeOne: 1,
  twoJediWalkIntoACantina: 2,
  episodeThree: 3,
  mayTheFourth: 4,
};

3.8 Only quote properties that are invalid identifiers. eslint: quote-props jscs: disallowQuotedKeysInObjects
Why? In general we consider it subjectively easier to read. It improves syntax highlighting, and is also more easily optimized by many JS engines.
```
// bad
const bad = {
  'foo': 3,
  'bar': 4,
  'data-blah': 5,
};

// good
const good = {
  foo: 3,
  bar: 4,
  'data-blah': 5,
};
```

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Arrays

4.1 Use the literal syntax for array creation. eslint: no-array-constructor
```
// bad
const items = new Array();

// good
const items = [];
```

4.2 Use Array#push instead of direct assignment to add items to an array.

const someStack = [];

// bad
someStack[someStack.length] = 'abracadabra';

// good
someStack.push('abracadabra');

4.3 Use array spreads ... to copy arrays.

// bad
const len = items.length;
const itemsCopy = [];
let i;

for (i = 0; i < len; i++) {
  itemsCopy[i] = items[i];
}

// good
const itemsCopy = [...items];

4.4 To convert an array-like object to an array, use Array#from.

const foo = document.querySelectorAll('.foo');
const nodes = Array.from(foo);

4.5 Use return statements in array method callbacks. It's ok to omit the return if the function body consists of a single statement following 8.2. eslint: array-callback-return

// good
[1, 2, 3].map((x) => {
  const y = x + 1;
  return x * y;
});

// good
[1, 2, 3].map(x => x + 1);

// bad
const flat = {};
[[0, 1], [2, 3], [4, 5]].reduce((memo, item, index) => {
  const flatten = memo.concat(item);
  flat[index] = memo.concat(item);
});

// good
const flat = {};
[[0, 1], [2, 3], [4, 5]].reduce((memo, item, index) => {
  const flatten = memo.concat(item);
  flat[index] = flatten;
  return flatten;
});

// bad
inbox.filter((msg) => {
  const { subject, author } = msg;
  if (subject === 'Mockingbird') {
    return author === 'Harper Lee';
  } else {
    return false;
  }
});

// good
inbox.filter((msg) => {
  const { subject, author } = msg;
  if (subject === 'Mockingbird') {
    return author === 'Harper Lee';
  }

  return false;
});

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Destructuring

5.1 Use object destructuring when accessing and using multiple properties of an object. jscs: requireObjectDestructuring

Why? Destructuring saves you from creating temporary references for those properties.

// bad
function getFullName(user) {
  const firstName = user.firstName;
  const lastName = user.lastName;

  return `${firstName} ${lastName}`;
}

// good
function getFullName(user) {
  const { firstName, lastName } = user;
  return `${firstName} ${lastName}`;
}

// best
function getFullName({ firstName, lastName }) {
  return `${firstName} ${lastName}`;
}

5.2 Use array destructuring. jscs: requireArrayDestructuring

const arr = [1, 2, 3, 4];

// bad
const first = arr[0];
const second = arr[1];

// good
const [first, second] = arr;

5.3 Use object destructuring for multiple return values, not array destructuring. jscs: disallowArrayDestructuringReturn

Why? You can add new properties over time or change the order of things without breaking call sites.

// bad
function processInput(input) {
  // then a miracle occurs
  return [left, right, top, bottom];
}

// the caller needs to think about the order of return data
const [left, __, top] = processInput(input);

// good
function processInput(input) {
  // then a miracle occurs
  return { left, right, top, bottom };
}

// the caller selects only the data they need
const { left, top } = processInput(input);

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Strings

6.1 Use single quotes '' for strings. eslint: quotes jscs: validateQuoteMarks

// bad
const name = "Capt. Janeway";

// good
const name = 'Capt. Janeway';

6.2 Strings that cause the line to go over 100 characters should be written across multiple lines using string concatenation.

6.3 Note: If overused, long strings with concatenation could impact performance. jsPerf & Discussion.

// bad
const errorMessage = 'This is a super long error that was thrown because of Batman. When you stop to think about how Batman had anything to do with this, you would get nowhere fast.';

// bad
const errorMessage = 'This is a super long error that was thrown because \
of Batman. When you stop to think about how Batman had anything to do \
with this, you would get nowhere \
fast.';

// good
const errorMessage = 'This is a super long error that was thrown because ' +
  'of Batman. When you stop to think about how Batman had anything to do ' +
  'with this, you would get nowhere fast.';

6.4 When programmatically building up strings, use template strings instead of concatenation. eslint: prefer-template template-curly-spacing jscs: requireTemplateStrings

Why? Template strings give you a readable, concise syntax with proper newlines and string interpolation features.

// bad
function sayHi(name) {
  return 'How are you, ' + name + '?';
}

// bad
function sayHi(name) {
  return ['How are you, ', name, '?'].join();
}

// bad
function sayHi(name) {
  return `How are you, ${ name }?`;
}

// good
function sayHi(name) {
  return `How are you, ${name}?`;
}

6.5 Never use eval() on a string, it opens too many vulnerabilities.
6.6 Do not unnecessarily escape characters in strings. eslint: no-useless-escape
Why? Backslashes harm readability, thus they should only be present when necessary.
```
// bad
const foo = '\'this\' \i\s \"quoted\"';

// good
const foo = '\'this\' is "quoted"';
const foo = `'this' is "quoted"`;
```

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Functions

Try to keep functions names to follow the verb or verb + object naming convention. This denotes that the function is performing some action and is not a variable.
```
// bad
function messageId() {
  // ...stuff...
}

// good
function getMessageId() {
  // ...stuff...
}

// good
function load() {
  // ...stuff...
}
```
7.1 Use function declarations instead of function expressions. jscs: requireFunctionDeclarations
Why? Function declarations are named, so they're easier to identify in call stacks. Also, the whole body of a function declaration is hoisted, whereas only the reference of a function expression is hoisted. This rule makes it possible to always use Arrow Functions in place of function expressions.
```
// bad
const foo = function () {
};

// good
function foo() {
}
```
7.2 Wrap immediately invoked function expressions in parentheses. eslint: wrap-iife jscs: requireParenthesesAroundIIFE
Why? An immediately invoked function expression is a single unit - wrapping both it, and its invocation parens, in parens, cleanly expresses this. Note that in a world with modules everywhere, you almost never need an IIFE.
```
// immediately-invoked function expression (IIFE)
(function () {
  console.log('Welcome to the Internet. Please follow me.');
}());
```
7.3 Never declare a function in a non-function block (if, while, etc). Assign the function to a variable instead. Browsers will allow you to do it, but they all interpret it differently, which is bad news bears. eslint: no-loop-func

7.4 Note: ECMA-262 defines a block as a list of statements. A function declaration is not a statement. Read ECMA-262's note on this issue.

// bad
if (currentUser) {
  function test() {
    console.log('Nope.');
  }
}

// good
let test;
if (currentUser) {
  test = () => {
    console.log('Yup.');
  };
}

7.5 Never name a parameter arguments. This will take precedence over the arguments object that is given to every function scope.

// bad
function nope(name, options, arguments) {
  // ...stuff...
}

// good
function yup(name, options, args) {
  // ...stuff...
}

7.6 Never use arguments, opt to use rest syntax ... instead. eslint: prefer-rest-params
Why? ... is explicit about which arguments you want pulled. Plus, rest arguments are a real Array, and not merely Array-like like arguments.
```
// bad
function concatenateAll() {
  const args = Array.prototype.slice.call(arguments);
  return args.join('');
}

// good
function concatenateAll(...args) {
  return args.join('');
}
```

7.7 Use default parameter syntax rather than mutating function arguments.

// really bad
function handleThings(opts) {
  // No! We shouldn't mutate function arguments.
  // Double bad: if opts is falsy it'll be set to an object which may
  // be what you want but it can introduce subtle bugs.
  opts = opts || {};
  // ...
}

// still bad
function handleThings(opts) {
  if (opts === void 0) {
    opts = {};
  }
  // ...
}

// good
function handleThings(opts = {}) {
  // ...
}

7.8 Avoid side effects with default parameters.

Why? They are confusing to reason about.

var b = 1;
// bad
function count(a = b++) {
  console.log(a);
}
count();  // 1
count();  // 2
count(3); // 3
count();  // 3

7.9 Always put default parameters last.

// bad
function handleThings(opts = {}, name) {
  // ...
}

// good
function handleThings(name, opts = {}) {
  // ...
}

7.10 Never use the Function constructor to create a new function.
Why? Creating a function in this way evaluates a string similarly to eval(), which opens vulnerabilities.
```
// bad
var add = new Function('a', 'b', 'return a + b');

// still bad
var subtract = Function('a', 'b', 'return a - b');
```
7.11 Spacing in a function signature.
Why? Consistency is good, and you shouldn’t have to add or remove a space when adding or removing a name.
```
// bad
const f = function(){};
const g = function (){};
const h = function() {};

// good
const x = function () {};
const y = function a() {};
```
7.12 Never mutate parameters. eslint: no-param-reassign
Why? Manipulating objects passed in as parameters can cause unwanted variable side effects in the original caller.
```
// bad
function f1(obj) {
  obj.key = 1;
};

// good
function f2(obj) {
  const key = Object.prototype.hasOwnProperty.call(obj, 'key') ? obj.key : 1;
};
```
7.13 Never reassign parameters. eslint: no-param-reassign
Why? Reassigning parameters can lead to unexpected behavior, especially when accessing the arguments object. It can also cause optimization issues, especially in V8.
```
// bad
function f1(a) {
  a = 1;
}

function f2(a) {
  if (!a) { a = 1; }
}

// good
function f3(a) {
  const b = a || 1;
}

function f4(a = 1) {
}
```

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Arrow Functions

8.1 When you must use function expressions (as when passing an anonymous function), use arrow function notation. eslint: prefer-arrow-callback, arrow-spacing jscs: requireArrowFunctions
Why? It creates a version of the function that executes in the context of this, which is usually what you want, and is a more concise syntax.
Why not? If you have a fairly complicated function, you might move that logic out into its own function declaration.
```
// bad
[1, 2, 3].map(function (x) {
  const y = x + 1;
  return x * y;
});

// good
[1, 2, 3].map((x) => {
  const y = x + 1;
  return x * y;
});
```
8.2 If the function body consists of a single expression, omit the braces and use the implicit return. Otherwise, keep the braces and use a return statement. eslint: arrow-parens, arrow-body-style jscs: disallowParenthesesAroundArrowParam, requireShorthandArrowFunctions
Why? Syntactic sugar. It reads well when multiple functions are chained together.
Why not? If you plan on returning an object.
```
// bad
[1, 2, 3].map(number => {
  const nextNumber = number + 1;
  `A string containing the ${nextNumber}.`;
});

// good
[1, 2, 3].map(number => `A string containing the ${number}.`);

// good
[1, 2, 3].map((number) => {
  const nextNumber = number + 1;
  return `A string containing the ${nextNumber}.`;
});
```

8.3 In case the expression spans over multiple lines, wrap it in parentheses for better readability.

Why? It shows clearly where the function starts and ends.

// bad
[1, 2, 3].map(number => 'As time went by, the string containing the ' +
  `${number} became much longer. So we needed to break it over multiple ` +
  'lines.'
);

// good
[1, 2, 3].map(number => (
  `As time went by, the string containing the ${number} became much ` +
  'longer. So we needed to break it over multiple lines.'
));

8.4 If your function takes a single argument and doesn’t use braces, omit the parentheses. Otherwise, always include parentheses around arguments. eslint: arrow-parens jscs: disallowParenthesesAroundArrowParam

Why? Less visual clutter.

// bad
[1, 2, 3].map((x) => x * x);

// good
[1, 2, 3].map(x => x * x);

// good
[1, 2, 3].map(number => (
  `A long string with the ${number}. It’s so long that we’ve broken it ` +
  'over multiple lines!'
));

// bad
[1, 2, 3].map(x => {
  const y = x + 1;
  return x * y;
});

// good
[1, 2, 3].map((x) => {
  const y = x + 1;
  return x * y;
});

8.5 Avoid confusing arrow function syntax (=>) with comparison operators (<=, >=). eslint: no-confusing-arrow

// bad
const itemHeight = item => item.height > 256 ? item.largeSize : item.smallSize;

// bad
const itemHeight = (item) => item.height > 256 ? item.largeSize : item.smallSize;

// good
const itemHeight = (item) => { return item.height > 256 ? item.largeSize : item.smallSize; }

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Classes & Constructors

9.1 Always use class. Avoid manipulating prototype directly.

Why? class syntax is more concise and easier to reason about.

// bad
function Queue(contents = []) {
  this.queue = [...contents];
}
Queue.prototype.pop = function () {
  const value = this.queue[0];
  this.queue.splice(0, 1);
  return value;
};

// good
class Queue {
  constructor(contents = []) {
    this.queue = [...contents];
  }
  pop() {
    const value = this.queue[0];
    this.queue.splice(0, 1);
    return value;
  }
}
```

9.2 Use extends for inheritance.

Why? It is a built-in way to inherit prototype functionality without breaking instanceof.

// bad
const inherits = require('inherits');
function PeekableQueue(contents) {
  Queue.apply(this, contents);
}
inherits(PeekableQueue, Queue);
PeekableQueue.prototype.peek = function () {
  return this._queue[0];
}

// good
class PeekableQueue extends Queue {
  peek() {
    return this._queue[0];
  }
}

9.3 Methods can return this to help with method chaining.

// bad
Jedi.prototype.jump = function () {
  this.jumping = true;
  return true;
};

Jedi.prototype.setHeight = function (height) {
  this.height = height;
};

const luke = new Jedi();
luke.jump(); // => true
luke.setHeight(20); // => undefined

// good
class Jedi {
  jump() {
    this.jumping = true;
    return this;
  }

  setHeight(height) {
    this.height = height;
    return this;
  }
}

const luke = new Jedi();

luke.jump()
  .setHeight(20);

9.4 It's okay to write a custom toString() method, just make sure it works successfully and causes no side effects.

class Jedi {
  constructor(options = {}) {
    this.name = options.name || 'no name';
  }

  getName() {
    return this.name;
  }

  toString() {
    return `Jedi - ${this.getName()}`;
  }
}

9.5 Classes have a default constructor if one is not specified. An empty constructor function or one that just delegates to a parent class is unnecessary. eslint: no-useless-constructor

// bad
class Jedi {
  constructor() {}

  getName() {
    return this.name;
  }
}

// bad
class Rey extends Jedi {
  constructor(...args) {
    super(...args);
  }
}

// good
class Rey extends Jedi {
  constructor(...args) {
    super(...args);
    this.name = 'Rey';
  }
}

9.6 Avoid duplicate class members. eslint: no-dupe-class-members
Why? Duplicate class member declarations will silently prefer the last one - having duplicates is almost certainly a bug.
```
// bad
class Foo {
  bar() { return 1; }
  bar() { return 2; }
}

// good
class Foo {
  bar() { return 1; }
}

// good
class Foo {
  bar() { return 2; }
}
```

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Modules

10.1 Always use modules (import/export) over a non-standard module system. You can always transpile to your preferred module system.

Why? Modules are the future, let's start using the future now.

// bad
const AirbnbStyleGuide = require('./AirbnbStyleGuide');
module.exports = AirbnbStyleGuide.es6;

// ok
import AirbnbStyleGuide from './AirbnbStyleGuide';
export default AirbnbStyleGuide.es6;

// best
import { es6 } from './AirbnbStyleGuide';
export default es6;

10.2 Do not use wildcard imports.

Why? This makes sure you have a single default export.

// bad
import * as AirbnbStyleGuide from './AirbnbStyleGuide';

// good
import AirbnbStyleGuide from './AirbnbStyleGuide';

10.3 And do not export directly from an import.
Why? Although the one-liner is concise, having one clear way to import and one clear way to export makes things consistent.
```
// bad
// filename es6.js
export { es6 as default } from './airbnbStyleGuide';

// good
// filename es6.js
import { es6 } from './AirbnbStyleGuide';
export default es6;
```

10.4 Only import from a path in one place. eslint: no-duplicate-imports

Why? Having multiple lines that import from the same path can make code harder to maintain.

// bad
import foo from 'foo';
// … some other imports … //
import { named1, named2 } from 'foo';

// good
import foo, { named1, named2 } from 'foo';

// good
import foo, {
  named1,
  named2,
} from 'foo';

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Iterators and Generators

11.1 Don't use iterators. Prefer JavaScript's higher-order functions like map() and reduce() instead of loops like for-of. eslint: no-iterator

Why? This enforces our immutable rule. Dealing with pure functions that return values is easier to reason about than side effects.

const numbers = [1, 2, 3, 4, 5];

// bad
let sum = 0;
for (let num of numbers) {
  sum += num;
}

sum === 15;

// good
let sum = 0;
numbers.forEach(num => sum += num);
sum === 15;

// best (use the functional force)
const sum = numbers.reduce((total, num) => total + num, 0);
sum === 15;

11.2 Don't use generators for now.
Why? They don't transpile well to ES5.

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Properties

12.1 Use dot notation when accessing properties. eslint: dot-notation jscs: requireDotNotation

const luke = {
  jedi: true,
  age: 28,
};

// bad
const isJedi = luke['jedi'];

// good
const isJedi = luke.jedi;

12.2 Use bracket notation [] when accessing properties with a variable.

const luke = {
  jedi: true,
  age: 28,
};

function getProp(prop) {
  return luke[prop];
}

const isJedi = getProp('jedi');

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Variables

13.1 Always use const to declare variables. Not doing so will result in global variables. We want to avoid polluting the global namespace. Captain Planet warned us of that.
```
// bad
superPower = new SuperPower();

// good
const superPower = new SuperPower();
```
13.2 Use one const declaration per variable. eslint: one-var jscs: disallowMultipleVarDecl
Why? It's easier to add new variable declarations this way, and you never have to worry about swapping out a ; for a , or introducing punctuation-only diffs. You can also step through each declaration with the debugger, instead of jumping through all of them at once.
```
// bad
const items = getItems(),
    goSportsTeam = true,
    dragonball = 'z';

// bad
// (compare to above, and try to spot the mistake)
const items = getItems(),
    goSportsTeam = true;
    dragonball = 'z';

// good
const items = getItems();
const goSportsTeam = true;
const dragonball = 'z';
```

13.3 Group all your consts and then group all your lets.

Why? This is helpful when later on you might need to assign a variable depending on one of the previous assigned variables.

// bad
let i, len, dragonball,
    items = getItems(),
    goSportsTeam = true;

// bad
let i;
const items = getItems();
let dragonball;
const goSportsTeam = true;
let len;

// good
const goSportsTeam = true;
const items = getItems();
let dragonball;
let i;
let length;

13.4 Assign variables where you need them, but place them in a reasonable place.

Why? let and const are block scoped and not function scoped.

// bad - unnecessary function call
function checkName(hasName) {
  const name = getName();

  if (hasName === 'test') {
    return false;
  }

  if (name === 'test') {
    this.setName('');
    return false;
  }

  return name;
}

// good
function checkName(hasName) {
  if (hasName === 'test') {
    return false;
  }

  const name = getName();

  if (name === 'test') {
    this.setName('');
    return false;
  }

  return name;
}

Avoid reusing variables and especially don't change a variable's type with an assignment.

var filterAndConcat = function (strings) {

  // bad
  strings = strings.map(function (s) {
    return s.match(/^a/);
  });

  // really bad -- changing type from array to string.
  strings = strings.join(', ');

  return strings;

};

var filterAndConcat = function (stringList) {

// good
var myStringList = strings.map(function (s) {
  return s.match(/^my/);
});

// good
var myString = strings.join(', ');

return myString;

};

**[⬆ back to top](#table-of-contents)**


## Hoisting

<a name="hoisting--about"></a><a name="14.1"></a>
- [14.1](#hoisting--about) `var` declarations get hoisted to the top of their scope, their assignment does not. `const` and `let` declarations are blessed with a new concept called [Temporal Dead Zones (TDZ)](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/let#Temporal_dead_zone_and_errors_with_let). It's important to know why [typeof is no longer safe](http://es-discourse.com/t/why-typeof-is-no-longer-safe/15).

  ```javascript
  // we know this wouldn't work (assuming there
  // is no notDefined global variable)
  function example() {
    console.log(notDefined); // => throws a ReferenceError
  }

  // creating a variable declaration after you
  // reference the variable will work due to
  // variable hoisting. Note: the assignment
  // value of `true` is not hoisted.
  function example() {
    console.log(declaredButNotAssigned); // => undefined
    var declaredButNotAssigned = true;
  }

  // the interpreter is hoisting the variable
  // declaration to the top of the scope,
  // which means our example could be rewritten as:
  function example() {
    let declaredButNotAssigned;
    console.log(declaredButNotAssigned); // => undefined
    declaredButNotAssigned = true;
  }

  // using const and let
  function example() {
    console.log(declaredButNotAssigned); // => throws a ReferenceError
    console.log(typeof declaredButNotAssigned); // => throws a ReferenceError
    const declaredButNotAssigned = true;
  }
  ```

<a name="hoisting--anon-expressions"></a><a name="14.2"></a>
- [14.2](#hoisting--anon-expressions) Anonymous function expressions hoist their variable name, but not the function assignment.

  ```javascript
  function example() {
    console.log(anonymous); // => undefined

    anonymous(); // => TypeError anonymous is not a function

    var anonymous = function () {
      console.log('anonymous function expression');
    };
  }
  ```

<a name="hoisting--named-expresions"></a><a name="14.3"></a>
- [14.3](#hoisting--named-expresions) Named function expressions hoist the variable name, not the function name or the function body.

  ```javascript
  function example() {
    console.log(named); // => undefined

    named(); // => TypeError named is not a function

    superPower(); // => ReferenceError superPower is not defined

    var named = function superPower() {
      console.log('Flying');
    };
  }

  // the same is true when the function name
  // is the same as the variable name.
  function example() {
    console.log(named); // => undefined

    named(); // => TypeError named is not a function

    var named = function named() {
      console.log('named');
    }
  }
  ```

<a name="hoisting--declarations"></a><a name="14.4"></a>
- [14.4](#hoisting--declarations) Function declarations hoist their name and the function body.

  ```javascript
  function example() {
    superPower(); // => Flying

    function superPower() {
      console.log('Flying');
    }
  }
  ```

- For more information refer to [JavaScript Scoping & Hoisting](http://www.adequatelygood.com/2010/2/JavaScript-Scoping-and-Hoisting/) by [Ben Cherry](http://www.adequatelygood.com/).

**[⬆ back to top](#table-of-contents)**


## Comparison Operators & Equality

<a name="comparison--eqeqeq"></a><a name="15.1"></a>
- [15.1](#comparison--eqeqeq) Use `===` and `!==` over `==` and `!=`. eslint: [`eqeqeq`](http://eslint.org/docs/rules/eqeqeq.html)

<a name="comparison--if"></a><a name="15.2"></a>
- [15.2](#comparison--if) Conditional statements such as the `if` statement evaluate their expression using coercion with the `ToBoolean` abstract method and always follow these simple rules:

  + **Objects** evaluate to **true**
  + **Undefined** evaluates to **false**
  + **Null** evaluates to **false**
  + **Booleans** evaluate to **the value of the boolean**
  + **Numbers** evaluate to **false** if **+0, -0, or NaN**, otherwise **true**
  + **Strings** evaluate to **false** if an empty string `''`, otherwise **true**

  ```javascript
  if ([0] && []) {
    // true
    // an array (even an empty one) is an object, objects will evaluate to true
  }
  ```

<a name="comparison--shortcuts"></a><a name="15.3"></a>
- [15.3](#comparison--shortcuts) Use shortcuts.

  ```javascript
  // bad
  if (name !== '') {
    // ...stuff...
  }

  // good
  if (name) {
    // ...stuff...
  }

  // bad
  if (collection.length > 0) {
    // ...stuff...
  }

  // good
  if (collection.length) {
    // ...stuff...
  }
  ```

<a name="comparison--moreinfo"></a><a name="15.4"></a>
- [15.4](#comparison--moreinfo) For more information see [Truth Equality and JavaScript](http://javascriptweblog.wordpress.com/2011/02/07/truth-equality-and-javascript/#more-2108) by Angus Croll.

<a name="comparison--switch-blocks"></a><a name="15.5"></a>
- [15.5](#comparison--switch-blocks) Use braces to create blocks in `case` and `default` clauses that contain lexical declarations (e.g. `let`, `const`, `function`, and `class`).

> Why? Lexical declarations are visible in the entire `switch` block but only get initialized when assigned, which only happens when its `case` is reached. This causes problems when multiple `case` clauses attempt to define the same thing.

eslint rules: [`no-case-declarations`](http://eslint.org/docs/rules/no-case-declarations.html).

  ```javascript
  // bad
  switch (foo) {
    case 1:
      let x = 1;
      break;
    case 2:
      const y = 2;
      break;
    case 3:
      function f() {}
      break;
    default:
      class C {}
  }

  // good
  switch (foo) {
    case 1: {
      let x = 1;
      break;
    }
    case 2: {
      const y = 2;
      break;
    }
    case 3: {
      function f() {}
      break;
    }
    case 4:
      bar();
      break;
    default: {
      class C {}
    }
  }
  ```

<a name="comparison--nested-ternaries"></a><a name="15.6"></a>
- [15.6](#comparison--nested-ternaries) Ternaries should not be nested and generally be single line expressions.

  eslint rules: [`no-nested-ternary`](http://eslint.org/docs/rules/no-nested-ternary.html).

  ```javascript
  // bad
  const foo = maybe1 > maybe2
    ? "bar"
    : value1 > value2 ? "baz" : null;

  // better
  const maybeNull = value1 > value2 ? 'baz' : null;

  const foo = maybe1 > maybe2
    ? 'bar'
    : maybeNull;

  // best
  const maybeNull = value1 > value2 ? 'baz' : null;

  const foo = maybe1 > maybe2 ? 'bar' : maybeNull;
  ```

<a name="comparison--unneeded-ternary"></a><a name="15.7"></a>
- [15.7](#comparison--unneeded-ternary) Avoid unneeded ternary statements.

  eslint rules: [`no-unneeded-ternary`](http://eslint.org/docs/rules/no-unneeded-ternary.html).

  ```javascript
  // bad
  const foo = a ? a : b;
  const bar = c ? true : false;
  const baz = c ? false : true;

  // good
  const foo = a || b;
  const bar = !!c;
  const baz = !c;
  ```

**[⬆ back to top](#table-of-contents)**


## Blocks

<a name="blocks--braces"></a><a name="16.1"></a>
- [16.1](#blocks--braces) Use braces with all multi-line blocks.

  ```javascript
  // bad
  if (test)
    return false;

  // good
  if (test) return false;

  // good
  if (test) {
    return false;
  }

  // bad
  function foo() { return false; }

  // good
  function() {
    return false;
  }
  ```

<a name="blocks--cuddled-elses"></a><a name="16.2"></a>
- [16.2](#blocks--cuddled-elses) If you're using multi-line blocks with `if` and `else`, put `else` on the same line as your `if` block's closing brace. eslint: [`brace-style`](http://eslint.org/docs/rules/brace-style.html) jscs:  [`disallowNewlineBeforeBlockStatements`](http://jscs.info/rule/disallowNewlineBeforeBlockStatements)

  ```javascript
  // bad
  if (test) {
    thing1();
    thing2();
  }
  else {
    thing3();
  }

  // good
  if (test) {
    thing1();
    thing2();
  } else {
    thing3();
  }
  ```


**[⬆ back to top](#table-of-contents)**


## Comments

<a name="comments--multiline"></a><a name="17.1"></a>
- [17.1](#comments--multiline) Use `/** ... */` for multi-line comments. Include a description, specify types and values for all parameters and return values.

  ```javascript
  // bad
  // make() returns a new element
  // based on the passed in tag name
  //
  // @param {String} tag
  // @return {Element} element
  function make(tag) {

    // ...stuff...

    return element;
  }

  // good
  /**
   * make() returns a new element
   * based on the passed in tag name
   *
   * @param {String} tag
   * @return {Element} element
   */
  function make(tag) {

    // ...stuff...

    return element;
  }
  ```

<a name="comments--singleline"></a><a name="17.2"></a>
- [17.2](#comments--singleline) Use `//` for single line comments. Place single line comments on a newline above the subject of the comment. Put an empty line before the comment unless it's on the first line of a block.

  ```javascript
  // bad
  const active = true;  // is current tab

  // good
  // is current tab
  const active = true;

  // bad
  function getType() {
    console.log('fetching type...');
    // set the default type to 'no type'
    const type = this._type || 'no type';

    return type;
  }

  // good
  function getType() {
    console.log('fetching type...');

    // set the default type to 'no type'
    const type = this._type || 'no type';

    return type;
  }

  // also good
  function getType() {
    // set the default type to 'no type'
    const type = this._type || 'no type';

    return type;
  }
  ```

<a name="comments--actionitems"></a><a name="17.3"></a>
- [17.3](#comments--actionitems) Prefixing your comments with `FIXME` or `TODO` helps other developers quickly understand if you're pointing out a problem that needs to be revisited, or if you're suggesting a solution to the problem that needs to be implemented. These are different than regular comments because they are actionable. The actions are `FIXME: -- need to figure this out` or `TODO: -- need to implement`.

<a name="comments--fixme"></a><a name="17.4"></a>
- [17.4](#comments--fixme) Use `// FIXME:` to annotate problems.

  ```javascript
  class Calculator extends Abacus {
    constructor() {
      super();

      // FIXME: shouldn't use a global here
      total = 0;
    }
  }
  ```

<a name="comments--todo"></a><a name="17.5"></a>
- [17.5](#comments--todo) Use `// TODO:` to annotate solutions to problems.

  ```javascript
  class Calculator extends Abacus {
    constructor() {
      super();

      // TODO: total should be configurable by an options param
      this.total = 0;
    }
  }
  ```

**[⬆ back to top](#table-of-contents)**


## Whitespace

<a name="whitespace--spaces"></a><a name="18.1"></a>
- [18.1](#whitespace--spaces) Use soft tabs set to 2 spaces. eslint: [`indent`](http://eslint.org/docs/rules/indent.html) jscs: [`validateIndentation`](http://jscs.info/rule/validateIndentation)

  ```javascript
  // bad
  function foo() {
  ∙∙∙∙const name;
  }

  // bad
  function bar() {
  ∙const name;
  }

  // good
  function baz() {
  ∙∙const name;
  }
  ```

<a name="whitespace--before-blocks"></a><a name="18.2"></a>
- [18.2](#whitespace--before-blocks) Place 1 space before the leading brace. eslint: [`space-before-blocks`](http://eslint.org/docs/rules/space-before-blocks.html) jscs: [`requireSpaceBeforeBlockStatements`](http://jscs.info/rule/requireSpaceBeforeBlockStatements)

  ```javascript
  // bad
  function test(){
    console.log('test');
  }

  // good
  function test() {
    console.log('test');
  }

  // bad
  dog.set('attr',{
    age: '1 year',
    breed: 'Bernese Mountain Dog'
  });

  // good
  dog.set('attr', {
    age: '1 year',
    breed: 'Bernese Mountain Dog'
  });
  ```

<a name="whitespace--around-keywords"></a><a name="18.3"></a>
- [18.3](#whitespace--around-keywords) Place 1 space before the opening parenthesis in control statements (`if`, `while` etc.). Place no space between the argument list and the function name in function calls and declarations. eslint: [`keyword-spacing`](http://eslint.org/docs/rules/keyword-spacing.html) jscs: [`requireSpaceAfterKeywords`](http://jscs.info/rule/requireSpaceAfterKeywords)

  ```javascript
  // bad
  if(isJedi) {
    fight ();
  }

  // good
  if (isJedi) {
    fight();
  }

  // bad
  function fight () {
    console.log ('Swooosh!');
  }

  // good
  function fight() {
    console.log('Swooosh!');
  }

  //bad
  function(element) {
    console.log(element);
  }

  //good
  function (element) {
    console.log(element);
  }
  ```

<a name="whitespace--infix-ops"></a><a name="18.4"></a>
- [18.4](#whitespace--infix-ops) Set off operators with spaces. eslint: [`space-infix-ops`](http://eslint.org/docs/rules/space-infix-ops.html) jscs: [`requireSpaceBeforeBinaryOperators`](http://jscs.info/rule/requireSpaceBeforeBinaryOperators), [`requireSpaceAfterBinaryOperators`](http://jscs.info/rule/requireSpaceAfterBinaryOperators)

  ```javascript
  // bad
  const x=y+5;

  // good
  const x = y + 5;
  ```

<a name="whitespace--newline-at-end"></a><a name="18.5"></a>
- [18.5](#whitespace--newline-at-end) End files with a single newline character.

  ```javascript
  // bad
  (function (global) {
    // ...stuff...
  })(this);
  ```

  ```javascript
  // bad
  (function (global) {
    // ...stuff...
  })(this);↵
  ↵
  ```

  ```javascript
  // good
  (function (global) {
    // ...stuff...
  })(this);↵
  ```

<a name="whitespace--chains"></a><a name="18.6"></a>
- [18.6](#whitespace--chains) Use indentation when making long method chains (more than 2 method chains). Use a leading dot, which
  emphasizes that the line is a method call, not a new statement. eslint: [`newline-per-chained-call`](http://eslint.org/docs/rules/newline-per-chained-call) [`no-whitespace-before-property`](http://eslint.org/docs/rules/no-whitespace-before-property)

  ```javascript
  // bad
  $('#items').find('.selected').highlight().end().find('.open').updateCount();

  // bad
  $('#items').
    find('.selected').
      highlight().
      end().
    find('.open').
      updateCount();

  // good
  $('#items')
    .find('.selected')
      .highlight()
      .end()
    .find('.open')
      .updateCount();

  // bad
  const leds = stage.selectAll('.led').data(data).enter().append('svg:svg').classed('led', true)
      .attr('width', (radius + margin) * 2).append('svg:g')
      .attr('transform', 'translate(' + (radius + margin) + ',' + (radius + margin) + ')')
      .call(tron.led);

  // good
  const leds = stage.selectAll('.led')
      .data(data)
    .enter().append('svg:svg')
      .classed('led', true)
      .attr('width', (radius + margin) * 2)
    .append('svg:g')
      .attr('transform', 'translate(' + (radius + margin) + ',' + (radius + margin) + ')')
      .call(tron.led);

  // good
  const leds = stage.selectAll('.led').data(data);
  ```

<a name="whitespace--after-blocks"></a><a name="18.7"></a>
- [18.7](#whitespace--after-blocks) Leave a blank line after blocks and before the next statement. jscs: [`requirePaddingNewLinesAfterBlocks`](http://jscs.info/rule/requirePaddingNewLinesAfterBlocks)

  ```javascript
  // bad
  if (foo) {
    return bar;
  }
  return baz;

  // good
  if (foo) {
    return bar;
  }

  return baz;

  // bad
  const obj = {
    foo() {
    },
    bar() {
    },
  };
  return obj;

  // good
  const obj = {
    foo() {
    },

    bar() {
    },
  };

  return obj;

  // bad
  const arr = [
    function foo() {
    },
    function bar() {
    },
  ];
  return arr;

  // good
  const arr = [
    function foo() {
    },

    function bar() {
    },
  ];

  return arr;
  ```

<a name="whitespace--padded-blocks"></a><a name="18.8"></a>
- [18.8](#whitespace--padded-blocks) Do not pad your blocks with blank lines. eslint: [`padded-blocks`](http://eslint.org/docs/rules/padded-blocks.html) jscs:  [`disallowPaddingNewlinesInBlocks`](http://jscs.info/rule/disallowPaddingNewlinesInBlocks)

  ```javascript
  // bad
  function bar() {

    console.log(foo);

  }

  // also bad
  if (baz) {

    console.log(qux);
  } else {
    console.log(foo);

  }

  // good
  function bar() {
    console.log(foo);
  }

  // good
  if (baz) {
    console.log(qux);
  } else {
    console.log(foo);
  }
  ```

<a name="whitespace--in-parens"></a><a name="18.9"></a>
- [18.9](#whitespace--in-parens) Do not add spaces inside parentheses. eslint: [`space-in-parens`](http://eslint.org/docs/rules/space-in-parens.html) jscs: [`disallowSpacesInsideParentheses`](http://jscs.info/rule/disallowSpacesInsideParentheses)

  ```javascript
  // bad
  function bar( foo ) {
    return foo;
  }

  // good
  function bar(foo) {
    return foo;
  }

  // bad
  if ( foo ) {
    console.log(foo);
  }

  // good
  if (foo) {
    console.log(foo);
  }
  ```

<a name="whitespace--in-brackets"></a><a name="18.10"></a>
- [18.10](#whitespace--in-brackets) Do not add spaces inside brackets. eslint: [`array-bracket-spacing`](http://eslint.org/docs/rules/array-bracket-spacing.html) jscs: [`disallowSpacesInsideArrayBrackets`](http://jscs.info/rule/disallowSpacesInsideArrayBrackets)

  ```javascript
  // bad
  const foo = [ 1, 2, 3 ];
  console.log(foo[ 0 ]);

  // good
  const foo = [1, 2, 3];
  console.log(foo[0]);
  ```

<a name="whitespace--in-braces"></a><a name="18.11"></a>
- [18.11](#whitespace--in-braces) Add spaces inside curly braces. eslint: [`object-curly-spacing`](http://eslint.org/docs/rules/object-curly-spacing.html) jscs: [`disallowSpacesInsideObjectBrackets`](http://jscs.info/rule/disallowSpacesInsideObjectBrackets)

  ```javascript
  // bad
  const foo = {clark: 'kent'};

  // good
  const foo = { clark: 'kent' };
  ```

<a name="whitespace--max-len"></a><a name="18.12"></a>
- [18.12](#whitespace--max-len) Avoid having lines of code that are longer than 100 characters (including whitespace). eslint: [`max-len`](http://eslint.org/docs/rules/max-len.html) jscs: [`maximumLineLength`](http://jscs.info/rule/maximumLineLength)

  > Why? This ensures readability and maintainability.

  ```javascript
  // bad
  const foo = 'Whatever national crop flips the window. The cartoon reverts within the screw. Whatever wizard constrains a helpful ally. The counterpart ascends!';

  // bad
  $.ajax({ method: 'POST', url: 'https://airbnb.com/', data: { name: 'John' } }).done(() => console.log('Congratulations!')).fail(() => console.log('You have failed this city.'));

  // good
  const foo = 'Whatever national crop flips the window. The cartoon reverts within the screw. ' +
    'Whatever wizard constrains a helpful ally. The counterpart ascends!';

  // good
  $.ajax({
    method: 'POST',
    url: 'https://airbnb.com/',
    data: { name: 'John' },
  })
    .done(() => console.log('Congratulations!'))
    .fail(() => console.log('You have failed this city.'));
  ```

**[⬆ back to top](#table-of-contents)**

## Commas

<a name="commas--leading-trailing"></a><a name="19.1"></a>
- [19.1](#commas--leading-trailing) Leading commas: **Nope.** eslint: [`comma-style`](http://eslint.org/docs/rules/comma-style.html) jscs: [`requireCommaBeforeLineBreak`](http://jscs.info/rule/requireCommaBeforeLineBreak)

  ```javascript
  // bad
  const story = [
      once
    , upon
    , aTime
  ];

  // good
  const story = [
    once,
    upon,
    aTime
  ];

  // bad
  const hero = {
      firstName: 'Ada'
    , lastName: 'Lovelace'
    , birthYear: 1815
    , superPower: 'computers'
  };

  // good
  const hero = {
    firstName: 'Ada',
    lastName: 'Lovelace',
    birthYear: 1815,
    superPower: 'computers'
  };
  ```

<a name="commas--dangling"></a><a name="19.2"></a>
- [19.2](#commas--dangling) Additional trailing comma: **No** eslint: [`comma-dangle`](http://eslint.org/docs/rules/comma-dangle.html) jscs: [`requireTrailingComma`](http://jscs.info/rule/requireTrailingComma)

  > Why? This leads to cleaner git diffs. Also, transpilers like Babel will remove the additional trailing comma in the transpiled code which means you don't have to worry about the [trailing comma problem](es5/README.md#commas) in legacy browsers.

  ```javascript
  // bad
  const hero = {
    firstName: 'Florence',
    lastName: 'Nightingale',
  };

  // good
  const hero = {
    firstName: 'Florence',
    lastName: 'Nightingale'
  };
  ```

**[⬆ back to top](#table-of-contents)**


## Semicolons

<a name="semicolons--required"></a><a name="20.1"></a>
- [20.1](#20.1) **Yup.** eslint: [`semi`](http://eslint.org/docs/rules/semi.html) jscs: [`requireSemicolons`](http://jscs.info/rule/requireSemicolons)

  ```javascript
  // bad
  (function () {
    const name = 'Skywalker'
    return name
  })()

  // good
  (() => {
    const name = 'Skywalker';
    return name;
  }());

  // good (guards against the function becoming an argument when two files with IIFEs are concatenated)
  ;(() => {
    const name = 'Skywalker';
    return name;
  }());
  ```

  [Read more](http://stackoverflow.com/questions/7365172/semicolon-before-self-invoking-function/7365214%237365214).

**[⬆ back to top](#table-of-contents)**


## Type Casting & Coercion

<a name="coercion--explicit"></a><a name="21.1"></a>
- [21.1](#coercion--explicit) Perform type coercion at the beginning of the statement.

<a name="coercion--strings"></a><a name="21.2"></a>
- [21.2](#coercion--strings)  Strings:

  ```javascript
  // => this.reviewScore = 9;

  // bad
  const totalScore = this.reviewScore + ''; // invokes this.reviewScore.valueOf()

  // bad
  const totalScore = this.reviewScore.toString(); // isn't guaranteed to return a string

  // good
  const totalScore = String(this.reviewScore);
  ```

<a name="coercion--numbers"></a><a name="21.3"></a>
- [21.3](#coercion--numbers) Numbers: Use `Number` for type casting and `parseInt` always with a radix for parsing strings. eslint: [`radix`](http://eslint.org/docs/rules/radix)

  ```javascript
  const inputValue = '4';

  // bad
  const val = new Number(inputValue);

  // bad
  const val = +inputValue;

  // bad
  const val = inputValue >> 0;

  // bad
  const val = parseInt(inputValue);

  // good
  const val = Number(inputValue);

  // good
  const val = parseInt(inputValue, 10);
  ```

<a name="coercion--comment-deviations"></a><a name="21.4"></a>
- [21.4](#coercion--comment-deviations) If for whatever reason you are doing something wild and `parseInt` is your bottleneck and need to use Bitshift for [performance reasons](http://jsperf.com/coercion-vs-casting/3), leave a comment explaining why and what you're doing.

  ```javascript
  // good
  /**
   * parseInt was the reason my code was slow.
   * Bitshifting the String to coerce it to a
   * Number made it a lot faster.
   */
  const val = inputValue >> 0;
  ```

<a name="coercion--bitwise"></a><a name="21.5"></a>
- [21.5](#coercion--bitwise) **Note:** Be careful when using bitshift operations. Numbers are represented as [64-bit values](http://es5.github.io/#x4.3.19), but bitshift operations always return a 32-bit integer ([source](http://es5.github.io/#x11.7)). Bitshift can lead to unexpected behavior for integer values larger than 32 bits. [Discussion](https://github.com/airbnb/javascript/issues/109). Largest signed 32-bit Int is 2,147,483,647:

  ```javascript
  2147483647 >> 0 //=> 2147483647
  2147483648 >> 0 //=> -2147483648
  2147483649 >> 0 //=> -2147483647
  ```

<a name="coercion--booleans"></a><a name="21.6"></a>
- [21.6](#coercion--booleans) Booleans:

  ```javascript
  const age = 0;

  // bad
  const hasAge = new Boolean(age);

  // good
  const hasAge = Boolean(age);

  // good
  const hasAge = !!age;
  ```

**[⬆ back to top](#table-of-contents)**


## Naming Conventions

<a name="naming--descriptive"></a><a name="22.1"></a>
- [22.1](#naming--descriptive) Avoid single letter names. Be descriptive with your naming.

  ```javascript
  // bad
  function q() {
    // ...stuff...
  }

  // good
  function query() {
    // ..stuff..
  }
  ```

<a name="naming--camelCase"></a><a name="22.2"></a>
- [22.2](#naming--camelCase) Use camelCase when naming objects, functions, and instances. eslint: [`camelcase`](http://eslint.org/docs/rules/camelcase.html) jscs: [`requireCamelCaseOrUpperCaseIdentifiers`](http://jscs.info/rule/requireCamelCaseOrUpperCaseIdentifiers)

  ```javascript
  // bad
  const OBJEcttsssss = {};
  const this_is_my_object = {};
  function c() {}

  // good
  const thisIsMyObject = {};
  function thisIsMyFunction() {}
  ```

<a name="naming--PascalCase"></a><a name="22.3"></a>
- [22.3](#naming--PascalCase) Use PascalCase only when naming constructors or classes. eslint: [`new-cap`](http://eslint.org/docs/rules/new-cap.html) jscs: [`requireCapitalizedConstructors`](http://jscs.info/rule/requireCapitalizedConstructors)

  ```javascript
  // bad
  function user(options) {
    this.name = options.name;
  }

  const bad = new user({
    name: 'nope',
  });

  // good
  class User {
    constructor(options) {
      this.name = options.name;
    }
  }

  const good = new User({
    name: 'yup',
  });
  ```

<a name="naming--leading-underscore"></a><a name="22.4"></a>
- [22.4](#naming--leading-underscore) Use a leading underscore `_` when naming private properties. eslint: [`no-underscore-dangle`](http://eslint.org/docs/rules/no-underscore-dangle.html) jscs: [`disallowDanglingUnderscores`](http://jscs.info/rule/disallowDanglingUnderscores)

  ```javascript
  // bad
  this.__firstName__ = 'Panda';
  this.firstName_ = 'Panda';

  // good
  this._firstName = 'Panda';
  ```

<a name="naming--self-this"></a><a na

style guide lint angieslist

@everything-registry/sub-chunk-1130 @zalastax/nolb-angi

1.0.0

8 years ago

angieslist-javascript-styleguide v1.0.0