A mostly reasonable approach to JavaScript
- Types
- Objects
- Arrays
- Strings
- Functions
- Properties
- Variables
- Hoisting
- Conditional Expressions & Equality
- Blocks
- Comments
- Line Length
- Whitespace
- Commas
- Semicolons
- File Headers
- Type Casting & Coercion
- Naming Conventions
- Accessors
- Constructors
- Functional Style
- Events
- Modules
- jQuery
- ECMAScript 5 Compatibility
- Testing
- Parting Words
- Resources
- The JavaScript Style Guide Guide
- Contributors
- License
-
Primitives: When you access a primitive type you work directly on its value
string
number
boolean
null
undefined
var foo = 1, bar = foo; bar = 9; console.log(foo, bar); // => 1, 9
-
Complex: When you access a complex type you work on a reference to its value
object
array
function
var foo = [1, 2], bar = foo; bar[0] = 9; console.log(foo[0], bar[0]); // => 9, 9
-
Use the literal syntax for object creation.
// bad var item = new Object(); // good var item = {};
-
Don't use reserved words as keys. It won't work in IE8. More info
// bad var superman = { default: { clark: 'kent' }, private: true }; // good var superman = { defaults: { clark: 'kent' }, hidden: true };
-
Use readable synonyms in place of reserved words.
// bad var superman = { class: 'alien' }; // good var superman = { type: 'alien' };
-
Use the literal syntax for array creation
// bad var items = new Array(); // good var items = [];
-
If you don't know array length use Array#push.
var someStack = []; // bad someStack[someStack.length] = 'abracadabra'; // good someStack.push('abracadabra');
-
When you need to copy an array use Array#slice. jsPerf
var len = items.length, itemsCopy = [], i; // bad for (i = 0; i < len; i++) { itemsCopy[i] = items[i]; } // good itemsCopy = items.slice();
-
To convert an array-like object to an array, use Array#slice.
function trigger() { var args = Array.prototype.slice.call(arguments); ... }
-
Use single quotes
''
for strings// bad var name = "Bob Parr"; // good var name = 'Bob Parr'; // bad var fullName = "Bob " + this.lastName; // good var fullName = 'Bob ' + this.lastName;
-
Strings longer than 80 characters should be written across multiple lines using string concatenation.
-
Note: If overused, long strings with concatenation could impact performance. jsPerf & Discussion
// bad var 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 var 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 var 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.';
-
When programmatically building up a string, use Array#join instead of string concatenation. Mostly for IE: jsPerf.
var items, messages, length, i; messages = [{ state: 'success', message: 'This one worked.' }, { state: 'success', message: 'This one worked as well.' }, { state: 'error', message: 'This one did not work.' }]; length = messages.length; // bad function inbox(messages) { items = '<ul>'; for (i = 0; i < length; i++) { items += '<li>' + messages[i].message + '</li>'; } return items + '</ul>'; } // good function inbox(messages) { items = []; for (i = 0; i < length; i++) { items[i] = messages[i].message; } return '<ul><li>' + items.join('</li><li>') + '</li></ul>'; }
-
Function expressions:
// anonymous function expression var anonymous = function () { return true; }; // named function expression var named = function named() { return true; }; // immediately-invoked function expression (IIFE) (function () { console.log('Welcome to the Internet. Please follow me.'); })();
-
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.
-
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 var test; if (currentUser) { test = function test() { console.log('Yup.'); }; }
-
Never name a parameter
arguments
, this will take precedence over thearguments
object that is given to every function scope.// bad function nope(name, options, arguments) { // ...stuff... } // good function yup(name, options, args) { // ...stuff... }
-
Use dot notation when accessing properties.
var luke = { jedi: true, age: 28 }; // bad var isJedi = luke['jedi']; // good var isJedi = luke.jedi;
-
Use subscript notation
[]
when accessing properties with a variable.var luke = { jedi: true, age: 28 }; function getProp(prop) { return luke[prop]; } var isJedi = getProp('jedi');
-
Always use
var
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 var superPower = new SuperPower();
-
Use one
var
declaration for multiple variables and declare each variable on a newline.// bad var items = getItems(); var goSportsTeam = true; var dragonball = 'z'; // good var items = getItems(), goSportsTeam = true, dragonball = 'z';
-
Declare unassigned variables last. This is helpful when later on you might need to assign a variable depending on one of the previous assigned variables.
// bad var i, len, dragonball, items = getItems(), goSportsTeam = true; // bad var i, items = getItems(), dragonball, goSportsTeam = true, len; // good var items = getItems(), goSportsTeam = true, dragonball, length, i;
-
Assign variables at the top of their scope. This helps avoid issues with variable declaration and assignment hoisting related issues.
// bad function () { test(); console.log('doing stuff..'); //..other stuff.. var name = getName(); if (name === 'test') { return false; } return name; } // good function () { var name = getName(); test(); console.log('doing stuff..'); //..other stuff.. if (name === 'test') { return false; } return name; } // bad function () { var name = getName(); if (!arguments.length) { return false; } return true; } // good function () { if (!arguments.length) { return false; } var name = getName(); return true; }
-
Only use single line for each variable.
// bad function () { var count = 0, options = { name: 'Luke', race: 'Jedi' }, i; // ... } // good function () { var count = 0, options, i; options = { name: 'Luke', race: 'Jedi' }; // ... }
-
For readability, only use single comment line for a variable if necessary. Prefer documenting variable in the function documentation.
// bad function () { var count, /* Hash that contain character options. * * @typedef options * @property {String} name - Name of the character. * @property {String} race - Race of the character. */ options, // index for the for loop. i; // ... } // better function () { var count, // character's options hash options, i; } // good function () { var count, characterOptions, i; // ... } // good /** * ... * * Internally, character's options are stored in the `options` hash. */ function () { var count, options, i; }
-
Variable declarations get hoisted to the top of their scope, their assignment does not.
// 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() { var declaredButNotAssigned; console.log(declaredButNotAssigned); // => undefined declaredButNotAssigned = true; }
-
Anonymous function expressions hoist their variable name, but not the function assignment.
function example() { console.log(anonymous); // => undefined anonymous(); // => TypeError anonymous is not a function var anonymous = function () { console.log('anonymous function expression'); }; }
-
Named function expressions hoist the variable name, not the function name or the function body.
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'); } }
-
Function declarations hoist their name and the function body.
function example() { superPower(); // => Flying function superPower() { console.log('Flying'); } }
-
For more information refer to JavaScript Scoping & Hoisting by Ben Cherry
-
Use
===
and!==
over==
and!=
. -
Conditional expressions are evaluated using coercion with the
ToBoolean
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
if ([0]) { // true // An array is an object, objects evaluate to true }
-
Use shortcuts.
// bad if (name !== '') { // ...stuff... } // good if (name) { // ...stuff... } // bad if (collection.length > 0) { // ...stuff... } // good if (collection.length) { // ...stuff... }
-
For more information see Truth Equality and JavaScript by Angus Croll
-
Use braces with all multi-line blocks.
// bad if (test) return false; // good if (test) return false; // good if (test) { return false; } // bad function () { return false; } // good function () { return false; }
-
Put
else
andcatch
on the same line with closing brace.// bad if (test) { return true; } else { return false; } // good if (test) { return 1; } else if (anotherTest) { return 0; } else { return -1; } // bad try { dragonsBeHere(); } catch (e) { log.error('very bad: ' + e); } // good try { dragonsBeHere(); } catch (e) { log.error('very bad: ' + e); }
-
Use following format for function/class comments:
/** * */
-
Other (random) multiline comments should take either of the following two forms:
/* * */ // // //
-
In function comments, include description, specify types and values for necessary parameters and return values.
-
First sentence of the function docstring should fit on one line and should prescribe the function's effect as a command ("Do this", "Return that"), not as a description; e.g. don't write "Returns the pathname ..."
-
Use JSDoc
-
You don't always have to document every parameter and return value if they are obvious.
-
Use
@typedef
to specify complex structures.// 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 /** * Return a new element. * * This is a longer description of the function and will * give all the necessary details. * * @param {String} tag - descriptive tag * @returns {Element} element */ function make(tag) { // ...stuff... return element; }
-
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.// bad function getType() { console.log('fetching type...'); // set the default type to 'no type' var type = this._type || 'no type'; return type; } // good function getType() { console.log('fetching type...'); // set the default type to 'no type' var type = this._type || 'no type'; return type; }
-
Use
@todo
to annotate todosfunction Calculator() { // @todo total should be configurable by an options param this.total = 0; return this; }
**[⬆ back to top](#table-of-contents)**
## Line Length
All JSHint rules should be set to max 100 char line length. There are some
cases where it is actually better for readability if this rule is broken. A
good example would be a REST API definition on the server side. In those
cases, override the JSHint rule for that code block. For example:
```javascript
/*jshint maxlen:200*/
...
{
name: 'releaseServiceWindow',
version: 1,
urls: [
{ path: '/schedule/{sid}/service-window/', name: 'schedule/serviceWindow' },
{ path: '/schedule/{sid}/service-window/{swid}', name: 'schedule/serviceWindow/*'}
]
},
...
/*jshint maxlen:100*/
```
**[⬆ back to top](#table-of-contents)**
## Whitespace
- Use soft tabs set to 4 spaces
```javascript
// bad
function () {
var name;
}
// bad
function () {
∙var name;
}
// good
function () {
∙∙∙∙var name;
}
```
- Place 1 space before the leading brace.
```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'
});
```
- Place 1 space after keywords (such as `if`, `for` and `function`).
```javascript
// bad
var foo = function() {
alert('hello');
};
// good
var foo = function () {
alert('hello');
};
```
- Set off operators with spaces.
```javascript
// bad
var x=y+5;
// good
var x = y + 5;
```
- 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);↵
```
- Use indentation when making long method chains.
```javascript
// bad
$('#items').find('.selected').highlight().end().find('.open').updateCount();
// good
$('#items')
.find('.selected')
.highlight()
.end()
.find('.open')
.updateCount();
// bad
var leds = stage.selectAll('.led').data(data).enter().append('svg:svg').class('led', true)
.attr('width', (radius + margin) * 2).append('svg:g')
.attr('transform', 'translate(' + (radius + margin) + ',' + (radius + margin) + ')')
.call(tron.led);
// good
var leds = stage.selectAll('.led')
.data(data)
.enter().append('svg:svg')
.class('led', true)
.attr('width', (radius + margin) * 2)
.append('svg:g')
.attr('transform', 'translate(' + (radius + margin) + ',' + (radius + margin) + ')')
.call(tron.led);
```
**[⬆ back to top](#table-of-contents)**
## Commas
- Leading commas: **Nope.**
```javascript
// bad
var once
, upon
, aTime;
// good
var once,
upon,
aTime;
// bad
var hero = {
firstName: 'Bob'
, lastName: 'Parr'
, heroName: 'Mr. Incredible'
, superPower: 'strength'
};
// good
var hero = {
firstName: 'Bob',
lastName: 'Parr',
heroName: 'Mr. Incredible',
superPower: 'strength'
};
```
- Additional trailing comma: **Nope.** This can cause problems with IE6/7 and
IE9 if it's in quirksmode. Also, in some implementations of ES3 would add
length to an array if it had an additional trailing comma. This was
clarified in ES5 ([source](http://es5.github.io/#D)):
> Edition 5 clarifies the fact that a trailing comma at the end of an
ArrayInitialiser does not add to the length of the array. This is not a
semantic change from Edition 3 but some implementations may have previously
misinterpreted this.
It is fine to use the extra comma in node.js environment.
```javascript
// bad
var hero = {
firstName: 'Kevin',
lastName: 'Flynn',
};
var heroes = [
'Batman',
'Superman',
];
// good
var hero = {
firstName: 'Kevin',
lastName: 'Flynn'
};
var heroes = [
'Batman',
'Superman'
];
```
**[⬆ back to top](#table-of-contents)**
## Semicolons
- **Yup.**
```javascript
// bad
(function () {
var name = 'Skywalker'
return name
})()
// good
(function () {
var name = 'Skywalker';
return name;
})();
// good
;(function () {
var name = 'Skywalker';
return name;
})();
```
**[⬆ back to top](#table-of-contents)**
## File Headers
All JavaScript files should have the following file header and footer:
```javascript
// -*- coding: utf-8 -*-
// filename.js
// created: 2014-05-22 08:10:10
//
//
// filename.js ends here
-
Perform type coercion at the beginning of the statement.
-
Strings:
// => this.reviewScore = 9; // bad var totalScore = this.reviewScore + ''; // good var totalScore = '' + this.reviewScore; // bad var totalScore = '' + this.reviewScore + ' total score'; // good var totalScore = this.reviewScore + ' total score';
-
Use
parseInt
for Numbers and always with a radix for type casting.var inputValue = '4'; // bad var val = new Number(inputValue); // bad var val = +inputValue; // bad var val = inputValue >> 0; // bad var val = parseInt(inputValue); // good var val = Number(inputValue); // good var val = parseInt(inputValue, 10);
-
If for whatever reason you are doing something wild and
parseInt
is your bottleneck and need to use Bitshift for performance reasons, leave a comment explaining why and what you're doing.// good /** * parseInt was the reason my code was slow. * Bitshifting the String to coerce it to a * Number made it a lot faster. */ var val = inputValue >> 0;
-
Note: Be careful when using bitshift operations. Numbers are represented as 64-bit values, but Bitshift operations always return a 32-bit integer (source). Bitshift can lead to unexpected behavior for integer values larger than 32 bits. Discussion. Largest signed 32-bit Int is 2,147,483,647:
2147483647 >> 0 //=> 2147483647 2147483648 >> 0 //=> -2147483648 2147483649 >> 0 //=> -2147483647
-
Booleans:
var age = 0; // bad var hasAge = new Boolean(age); // good var hasAge = Boolean(age); // good var hasAge = !!age;
-
Avoid single letter names. Be descriptive with your naming.
// bad function q() { // ...stuff... } // good function query() { // ..stuff.. }
-
Use camelCase when naming objects, functions, and instances
// bad var OBJEcttsssss = {}; var this_is_my_object = {}; function c() {} var u = new user({ name: 'Bob Parr' }); // good var thisIsMyObject = {}; function thisIsMyfunction () {} var user = new User({ name: 'Bob Parr' });
-
Use PascalCase when naming constructors or classes
// bad function user(options) { this.name = options.name; } var bad = new user({ name: 'nope' }); // good function User(options) { this.name = options.name; } var good = new User({ name: 'yup' });
-
Use a leading underscore
_
when naming private properties (note that this is not necessary when using the module pattern or when protecting ES5 style variables withObject.create()
)// bad this.__firstName__ = 'Panda'; this.firstName_ = 'Panda'; // good this._firstName = 'Panda';
-
When saving a reference to
this
useme
.// bad function () { var self = this; return function () { console.log(self); }; } // bad function () { var _this = this; return function () { console.log(_this); }; } // good function () { var me = this; return function () { console.log(me); }; }
-
When implementing the JavaScript module pattern use
that
for referencing the "public" interface.var mymodule = (function mymodule() { var that = {}, privateCounter = 0; that.increment = function increment() { privateCounter += 1; return privateCounter; }; return that; })();
-
Note: IE8 and below exhibit some quirks with named function expressions. See http://kangax.github.io/nfe/ for more info.
- Accessor functions (simle getters and setters) for properties are not required
-
Assign methods to the prototype object, instead of overwriting the prototype with a new object. Overwriting the prototype makes inheritance impossible: by resetting the prototype you'll overwrite the base!
function Jedi() { console.log('new jedi'); } // bad Jedi.prototype = { fight: function fight() { console.log('fighting'); }, block: function block() { console.log('blocking'); } }; // good Jedi.prototype.fight = function fight() { console.log('fighting'); }; Jedi.prototype.block = function block() { console.log('blocking'); };
-
Methods should 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; }; var luke = new Jedi(); luke.jump(); // => true luke.setHeight(20) // => undefined // good Jedi.prototype.jump = function () { this.jumping = true; return this; }; Jedi.prototype.setHeight = function (height) { this.height = height; return this; }; var luke = new Jedi(); luke.jump() .setHeight(20);
-
It's okay to write a custom toString() method, just make sure it works successfully and causes no side effects.
function Jedi(options) { options || (options = {}); this.name = options.name || 'no name'; } Jedi.prototype.getName = function getName() { return this.name; }; Jedi.prototype.toString = function toString() { return 'Jedi - ' + this.getName(); };
- Avoid generic for-loops (i.e.
for (i = 0; i < array.length; i += 1)
) because- They make code difficult to read
- They may have all kinds of side effects
- Prefer using functional programming constructs such as
map
: to convert an array to another arrayreduce
: to reduce an array of items into a single valuefilter
: to filter out unwanted elements
- Familiarize yourself with all different functions available in the lodash library. When it comes to dealing with collections, most of the time it already has what you would otherwise have to implement yourself.
- Using these functions makes it easy for the reader to quickly see what the code is supposed to be doing and the reader can trust that the code inside the loop doesn't (must not) have any side effects.
forEach
is the only exception where we allow the code inside the loop to have side effects since it has been used for drop-in replacement for more traditionalfor (i = 0; i < array.length; i += 1)
construct.- Sometimes though, for performance reasons for large collections, you may want to consider replacing subsequent functional constructs with single for-loop where you do many things at once. This should be vary rare however.
-
When attaching data payloads to events (whether DOM events or something more proprietary like Backbone events), pass a hash instead of a raw value. This allows a subsequent contributor to add more data to the event payload without finding and updating every handler for the event. For example, instead of:
// bad $(this).trigger('listingUpdated', listing.id); ... $(this).on('listingUpdated', function (e, listingId) { // do something with listingId });
prefer:
// good $(this).trigger('listingUpdated', { listingId : listing.id }); ... $(this).on('listingUpdated', function (e, data) { // do something with data.listingId });
- In Node.js files should be named with camelCase.
- In Ember projects files should be named with hyphens (e.g.
route-header.js
). - All files should use
utf-8
encoding. - Always declare
'use strict';
at the top of the module.
-
Prefix jQuery object variables with a
$
.// bad var sidebar = $('.sidebar'); // good var $sidebar = $('.sidebar');
-
Cache jQuery lookups.
// bad function setSidebar() { $('.sidebar').hide(); // ...stuff... $('.sidebar').css({ 'background-color': 'pink' }); } // good function setSidebar() { var $sidebar = $('.sidebar'); $sidebar.hide(); // ...stuff... $sidebar.css({ 'background-color': 'pink' }); }
-
For DOM queries use Cascading
$('.sidebar ul')
or parent > child$('.sidebar > ul')
. jsPerf -
Use
find
with scoped jQuery object queries.// bad $('ul', '.sidebar').hide(); // bad $('.sidebar').find('ul').hide(); // good $('.sidebar ul').hide(); // good $('.sidebar > ul').hide(); // good $sidebar.find('ul').hide();
- Refer to Kangax's ES5 compatibility table
-
Gather all private functions in private variable called
internals
-
Expose the
internals
variable when running testsvar internals = {}; internals.myPrivateFunction = function () { // do private stuff }; // in the end of the module expose internals for tests if (process.env.NODE_ENV === 'test') { exports.internals = internals; }
Remeber that:
"Code is read many more times than it is written"
So, it's all about readability. If any of the conventions laid out on this page contradicts with readability in a given scenario, feel free to break the convention to make way for better readability.
Bear in mind though that linting errors are considered real errors and all projects must pass with zero linting errors. Therefore, if you have to break one of the JSHint rules, override the rule for that file or for that code block instead of changing the global project rules.
Read This
Performance
- On Layout & Web Performance
- String vs Array Concat
- Try/Catch Cost In a Loop
- Bang Function
- jQuery Find vs Context, Selector
- innerHTML vs textContent for script text
- Long String Concatenation
Other Styleguides
- Google JavaScript Style Guide
- jQuery Core Style Guidelines
- Principles of Writing Consistent, Idiomatic JavaScript
Other Styles
- Naming this in nested functions - Christian Johansen
- Conditional Callbacks
- Popular JavaScript Coding Conventions on Github
Further Reading
- Understanding JavaScript Closures - Angus Croll
- Basic JavaScript for the impatient programmer - Dr. Axel Rauschmayer
- You Might Not Need jQuery - Zack Bloom & Adam Schwartz
- ES6 Features - Luke Hoban
Books
- JavaScript: The Good Parts - Douglas Crockford
- JavaScript Patterns - Stoyan Stefanov
- Pro JavaScript Design Patterns - Ross Harmes and Dustin Diaz
- High Performance Web Sites: Essential Knowledge for Front-End Engineers - Steve Souders
- Maintainable JavaScript - Nicholas C. Zakas
- JavaScript Web Applications - Alex MacCaw
- Pro JavaScript Techniques - John Resig
- Smashing Node.js: JavaScript Everywhere - Guillermo Rauch
- Secrets of the JavaScript Ninja - John Resig and Bear Bibeault
- Human JavaScript - Henrik Joreteg
- Superhero.js - Kim Joar Bekkelund, Mads Mobæk, & Olav Bjorkoy
- JSBooks
- Third Party JavaScript - Ben Vinegar and Anton Kovalyov
Blogs
- DailyJS
- JavaScript Weekly
- JavaScript, JavaScript...
- Bocoup Weblog
- Adequately Good
- NCZOnline
- Perfection Kills
- Ben Alman
- Dmitry Baranovskiy
- Dustin Diaz
- nettuts
(The MIT License)
Copyright (c) 2014 Airbnb
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.