The is_js npm package provides a collection of type-checking and validation functions. It allows developers to easily check the type of a variable, validate data, and perform various checks on strings, numbers, and other data types.

What are is_js's main functionalities?

Type Checking

This feature allows you to check the type of a variable. The code sample demonstrates how to check if a variable is a string, number, or array.

const is = require('is_js');
console.log(is.string('Hello')); // true
console.log(is.number(123)); // true
console.log(is.array([1, 2, 3])); // true

Presence Checks

This feature allows you to check for the presence or absence of values. The code sample shows how to check if an array is empty, if a value exists, and if a value is truthy.

const is = require('is_js');
console.log(is.empty([])); // true
console.log(is.existy(null)); // false
console.log(is.truthy(1)); // true

String Checks

This feature allows you to perform various checks on strings. The code sample demonstrates how to check if a string is a valid URL, email, or credit card number.

const is = require('is_js');
console.log(is.url('https://www.example.com')); // true
console.log(is.email('test@example.com')); // true
console.log(is.creditCard('4111111111111111')); // true

Environment Checks

This feature allows you to check the environment in which the code is running. The code sample shows how to check if the browser is Internet Explorer, if the device is mobile, and if the operating system is Windows.

const is = require('is_js');
console.log(is.ie()); // false (depends on the browser)
console.log(is.mobile()); // false (depends on the device)
console.log(is.windows()); // true (depends on the OS)

Other packages similar to is_js

is.js

####This is a general-purpose check library.

No dependencies
AMD, Node & browser ready

Type checks

is.arguments(value:any)

####Checks if the given value type is arguments. interfaces: not, all, any

var getArguments = function() {
    return arguments;
};
var arguments = getArguments();

is.arguments(arguments);
=> true

is.not.arguments({foo: 'bar'});
=> true

is.all.arguments(arguments, 'bar');
=> false

is.any.arguments(['foo'], arguments);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.arguments([arguments, 'foo', 'bar']);
=> false

is.array(value:any)

####Checks if the given value type is array. interfaces: not, all, any

is.array(['foo', 'bar', 'baz']);
=> true

is.not.array({foo: 'bar'});
=> true

is.all.array(['foo'], 'bar');
=> false

is.any.array(['foo'], 'bar');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.array([[1, 2], 'foo', 'bar']);
=> false

is.boolean(value:any)

####Checks if the given value type is boolean. interfaces: not, all, any

is.boolean(true);
=> true

is.not.boolean({foo: 'bar'});
=> true

is.all.boolean(true, 'bar');
=> false

is.any.boolean(true, 'bar');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.boolean([true, 'foo', 'bar']);
=> false

is.date(value:any)

####Checks if the given value type is date. interfaces: not, all, any

is.date(new Date());
=> true

is.not.date({foo: 'bar'});
=> true

is.all.date(new Date(), 'bar');
=> false

is.any.date(new Date(), 'bar');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.date([new Date(), 'foo', 'bar']);
=> false

is.error(value:any)

####Checks if the given value type is error. interfaces: not, all, any

is.error(new Error());
=> true

is.not.error({foo: 'bar'});
=> true

is.all.error(new Error(), 'bar');
=> false

is.any.error(new Error(), 'bar');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.error([new Error(), 'foo', 'bar']);
=> false

is.function(value:any)

####Checks if the given value type is function. interfaces: not, all, any

is.function(toString);
=> true

is.not.function({foo: 'bar'});
=> true

is.all.function(toString, 'bar');
=> false

is.any.function(toString, 'bar');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.function([toString, 'foo', 'bar']);
=> false

is.nan(value:any)

####Checks if the given value type is NaN. interfaces: not, all, any

is.nan(NaN);
=> true

is.not.nan(42);
=> true

is.all.nan(NaN, 1);
=> false

is.any.nan(NaN, 2);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.nan([NaN, 'foo', 1]);
=> false

is.null(value:any)

####Checks if the given value type is null. interfaces: not, all, any

is.null(null);
=> true

is.not.null(42);
=> true

is.all.null(null, 1);
=> false

is.any.null(null, 2);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.null([null, 'foo', 1]);
=> false

is.number(value:any)

####Checks if the given value type is number. interfaces: not, all, any

is.number(42);
=> true

is.not.number('42');
=> true

is.all.number('foo', 1);
=> false

is.any.number({}, 2);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.number([42, 'foo', 1]);
=> false

is.object(value:any)

####Checks if the given value type is object. interfaces: not, all, any

is.object({foo: 'bar'});
=> true

// functions are also returnin as true
is.object(toString);
=> true

is.not.object('foo');
=> true

is.all.object({}, 1);
=> false

is.any.object({}, 2);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.object([{}, new Object()]);
=> true

is.regexp(value:any)

####Checks if the given value type is RegExp. interfaces: not, all, any

is.regexp(/test/);
=> true

is.not.regexp(['foo']);
=> true

is.all.regexp(/test/, 1);
=> false

is.any.regexp(new RegExp('ab+c'), 2);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.regexp([{}, /test/]);
=> false

is.string(value:any)

####Checks if the given value type is string. interfaces: not, all, any

is.string('foo');
=> true

is.not.string(['foo']);
=> true

is.all.string('foo', 1);
=> false

is.any.string('foo', 2);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.string([{}, 'foo']);
=> false

is.char(value:any)

####Checks if the given value type is char. interfaces: not, all, any

is.char('f');
=> true

is.not.char(['foo']);
=> true

is.all.char('f', 1);
=> false

is.any.char('f', 2);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.char(['f', 'o', 'o']);
=> true

is.undefined(value:any)

####Checks if the given value type is undefined. interfaces: not, all, any

is.undefined(undefined);
=> true

is.not.undefined(null);
=> true

is.all.undefined(undefined, 1);
=> false

is.any.undefined(undefined, 2);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.undefined([{}, undefined]);
=> false

is.sameType(value:any, value:any)

####Checks if the given value types are same type. interface: not

is.sameType(42, 7);
=> true

is.sameType(42, '7');
=> false

is.not.sameType(42, 7);
=> false

Presence checks

is.empty(value:object|array|string)

####Checks if the given value is empty. interfaces: not, all, any

is.empty({});
=> true

is.empty([]);
=> true

is.empty('');
=> true

is.not.empty(['foo']);
=> true

is.all.empty('', {}, ['foo']);
=> false

is.any.empty([], 42);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.empty([{}, 'foo']);
=> false

is.existy(value:any)

####Checks if the given value is existy. (not null or undefined) interfaces: not, all, any

is.existy({});
=> true

is.existy(null);
=> false

is.not.existy(undefined);
=> true

is.all.existy(null, ['foo']);
=> false

is.any.existy(undefined, 42);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.existy([{}, 'foo']);
=> true

is.truthy(value:any)

####Checks if the given value is truthy. (existy and not false) interfaces: not, all, any

is.truthy(true);
=> true

is.truthy(null);
=> false

is.not.truthy(false);
=> true

is.all.truthy(null, true);
=> false

is.any.truthy(undefined, true);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.truthy([{}, true]);
=> true

is.falsy(value:any)

####Checks if the given value is falsy. interfaces: not, all, any

is.falsy(false);
=> true

is.falsy(null);
=> true

is.not.falsy(true);
=> true

is.all.falsy(null, false);
=> true

is.any.falsy(undefined, true);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.falsy([false, true, undefined]);
=> false

is.space(value:string)

####Checks if the given value is space. interfaces: not, all, any

is.space(' ');
=> true

is.space('foo');
=> false

is.not.space(true);
=> true

is.all.space(' ', 'foo');
=> false

is.any.space(' ', true);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.space([' ', 'foo', undefined]);
=> false

RegExp checks

is.url(value:any)

####Checks if the given value matches url regexp. interfaces: not, all, any

is.url('http://www.test.com');
=> true

is.url('foo');
=> false

is.not.url(true);
=> true

is.all.url('http://www.test.com', 'foo');
=> false

is.any.url('http://www.test.com', true);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.url(['http://www.test.com', 'foo', undefined]);
=> false

is.email(value:any)

####Checks if the given value matches email regexp. interfaces: not, all, any

is.email('test@test.com');
=> true

is.email('foo');
=> false

is.not.email('foo');
=> true

is.all.email('test@test.com', 'foo');
=> false

is.any.email('test@test.com', 'foo');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.email(['test@test.com', 'foo', undefined]);
=> false

is.creditCard(value:any)

####Checks if the given value matches credit card regexp. interfaces: not, all, any

is.creditCard(378282246310005);
=> true

is.creditCard(123);
=> false

is.not.creditCard(123);
=> true

is.all.creditCard(378282246310005, 123);
=> false

is.any.creditCard(378282246310005, 123);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.creditCard([378282246310005, 123, undefined]);
=> false

is.alphaNumeric(value:any)

####Checks if the given value matches alpha numeric regexp. interfaces: not, all, any

is.alphaNumeric('alphaNu3er1k');
=> true

is.alphaNumeric('*?');
=> false

is.not.alphaNumeric('*?');
=> true

is.all.alphaNumeric('alphaNu3er1k', '*?');
=> false

is.any.alphaNumeric('alphaNu3er1k', '*?');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.alphaNumeric(['alphaNu3er1k', '*?']);
=> false

is.timeString(value:any)

####Checks if the given value matches time string regexp. interfaces: not, all, any

is.timeString('13:45:30');
=> true

is.timeString('90:90:90');
=> false

is.not.timeString('90:90:90');
=> true

is.all.timeString('13:45:30', '90:90:90');
=> false

is.any.timeString('13:45:30', '90:90:90');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.timeString(['13:45:30', '90:90:90']);
=> false

is.dateString(value:any)

####Checks if the given value matches date string regexp. interfaces: not, all, any

is.dateString('11/11/2011');
=> true

is.dateString('90/11/2011');
=> false

is.not.dateString('90/11/2011');
=> true

is.all.dateString('11/11/2011', '90/11/2011');
=> false

is.any.dateString('11/11/2011', '90/11/2011');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.dateString(['11/11/2011', '90/11/2011']);
=> false

is.usZipCode(value:any)

####Checks if the given value matches US zip code regexp. interfaces: not, all, any

is.usZipCode('02201-1020');
=> true

is.usZipCode('123');
=> false

is.not.usZipCode('123');
=> true

is.all.usZipCode('02201-1020', '123');
=> false

is.any.usZipCode('02201-1020', '123');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.usZipCode(['02201-1020', '123']);
=> false

is.caPostalCode(value:any)

####Checks if the given value matches Canada postal code regexp. interfaces: not, all, any

is.caPostalCode('L8V3Y1');
=> true

is.caPostalCode('L8V 3Y1');
=> true

is.caPostalCode('123');
=> false

is.not.caPostalCode('123');
=> true

is.all.caPostalCode('L8V3Y1', '123');
=> false

is.any.caPostalCode('L8V3Y1', '123');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.caPostalCode(['L8V3Y1', '123']);
=> false

is.ukPostCode(value:any)

####Checks if the given value matches UK post code regexp. interfaces: not, all, any

is.ukPostCode('B184BJ');
=> true

is.ukPostCode('123');
=> false

is.not.ukPostCode('123');
=> true

is.all.ukPostCode('B184BJ', '123');
=> false

is.any.ukPostCode('B184BJ', '123');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.ukPostCode(['B184BJ', '123']);
=> false

is.nanpPhone(value:any)

####Checks if the given value matches North American numbering plan phone regexp. interfaces: not, all, any

is.nanpPhone('609-555-0175');
=> true

is.nanpPhone('123');
=> false

is.not.nanpPhone('123');
=> true

is.all.nanpPhone('609-555-0175', '123');
=> false

is.any.nanpPhone('609-555-0175', '123');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.nanpPhone(['609-555-0175', '123']);
=> false

is.eppPhone(value:any)

####Checks if the given value matches extensible provisioning protocol phone regexp. interfaces: not, all, any

is.eppPhone('+90.2322456789');
=> true

is.eppPhone('123');
=> false

is.not.eppPhone('123');
=> true

is.all.eppPhone('+90.2322456789', '123');
=> false

is.any.eppPhone('+90.2322456789', '123');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.eppPhone(['+90.2322456789', '123']);
=> false

is.socialSecurityNumber(value:any)

####Checks if the given value matches social security number regexp. interfaces: not, all, any

is.socialSecurityNumber('017-90-7890');
=> true

is.socialSecurityNumber('123');
=> false

is.not.socialSecurityNumber('123');
=> true

is.all.socialSecurityNumber('017-90-7890', '123');
=> false

is.any.socialSecurityNumber('017-90-7890', '123');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.socialSecurityNumber(['017-90-7890', '123']);
=> false

is.affirmative(value:any)

####Checks if the given value matches affirmative regexp. interfaces: not, all, any

is.affirmative('yes');
=> true

is.affirmative('no');
=> false

is.not.affirmative('no');
=> true

is.all.affirmative('yes', 'no');
=> false

is.any.affirmative('yes', 'no');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.affirmative(['yes', 'y', 'true', 't', 'ok', 'okay']);
=> true

is.hexadecimal(value:any)

####Checks if the given value matches hexadecimal regexp. interfaces: not, all, any

is.hexadecimal('f0f0f0');
=> true

is.hexadecimal(2.5);
=> false

is.not.hexadecimal('string');
=> true

is.all.hexadecimal('ff', 'f50');
=> true

is.any.hexadecimal('ff5500', true);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.hexadecimal(['fff', '333', 'f50']);
=> true

is.hexColor(value:any)

####Checks if the given value matches hexcolor regexp. interfaces: not, all, any

is.hexColor('#333');
=> true

is.hexColor('#3333');
=> false

is.not.hexColor(0.5);
=> true

is.all.hexColor('fff', 'f50');
=> true

is.any.hexColor('ff5500', 0.5);
=> false

// 'all' and 'any' interfaces can also take array parameter
is.all.hexColor(['fff', '333', 'f50']);
=> true

is.ip(value:string)

####Checks if the given value matches ip regexp interfaces: not, all, any

is.ip('198.156.23.5');
=> true

is.ip('1.2..5');
=> false

is.not.ip('8:::::::7');
=> true

is.all.ip('0:1::4:ff5:54:987:C', '123.123.123.123');
=> true

is.any.ip('123.8.4.3', '0.0.0.0');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.ip(['123.123.23.12', 'A:B:C:D:E:F:0:0']);
=> true

is.ipv4(value:string)

####Checks if the given value matches ipv4 regexp interfaces: not, all, any

is.ipv4('198.12.3.142');
=> true

is.ipv4('1.2..5');
=> false

is.not.ipv4('8:::::::7');
=> true

is.all.ipv4('198.12.3.142', '123.123.123.123');
=> true

is.any.ipv4('255.255.255.255', '850..1.4');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.ipv4(['198.12.3.142', '1.2.3']);
=> false

is.ipv6(value:string)

####Checks if the given value matches ipv6 regexp interfaces: not, all, any

is.ipv6('2001:DB8:0:0:1::1');
=> true

is.ipv6('985.12.3.4');
=> true

is.not.ipv6('8:::::::7');
=> true

is.all.ipv6('2001:DB8:0:0:1::1', '1:50:198:2::1:2:8');
=> true

is.any.ipv6('255.255.255.255', '2001:DB8:0:0:1::1');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.ipv6(['2001:DB8:0:0:1::1', '1.2.3']);
=> false

String checks

is.include(value:string, value:substring)

####Checks if the given string contains a substring. interface: not

is.include('Some text goes here', 'text');
=> true

is.include('test', 'text');
=> false

is.not.include('test', 'text');
=> true

is.upperCase(value:string)

####Checks if the given string is UPPERCASE. interfaces: not, all, any

is.upperCase('YEAP');
=> true

is.upperCase('nope');
=> false

is.not.upperCase('Nope');
=> true

is.all.upperCase('YEAP', 'nope');
=> false

is.any.upperCase('YEAP', 'nope');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.upperCase(['YEAP', 'ALL UPPERCASE']);
=> true

is.lowerCase(value:string)

####Checks if the given string is lowercase. interfaces: not, all, any

is.lowerCase('yeap');
=> true

is.lowerCase('NOPE');
=> false

is.not.lowerCase('Nope');
=> true

is.all.lowerCase('yeap', 'NOPE');
=> false

is.any.lowerCase('yeap', 'NOPE');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.lowerCase(['yeap', 'all lowercase']);
=> true

is.startWith(value:string, value:substring)

####Checks if the given string starts with substring. interface: not

is.startWith('yeap', 'ye');
=> true

is.startWith('nope', 'ye');
=> false

is.not.startWith('nope not that', 'not');
=> true

is.endWith(value:string, value:substring)

####Checks if the given string ends with substring. interfaces: not

is.endWith('yeap', 'ap');
=> true

is.endWith('nope', 'no');
=> false

is.not.endWith('nope not that', 'not');
=> true

is.endWith('yeap that one', 'one');
=> true

is.capitalized(value:string, value:substring)

####Checks if the given string is capitalized. interfaces: not, all, any

is.capitalized('Yeap');
=> true

is.capitalized('nope');
=> false

is.not.capitalized('nope not capitalized');
=> true

is.not.capitalized('nope Capitalized');
=> true

is.all.capitalized('Yeap', 'All', 'Capitalized');
=> true

is.any.capitalized('Yeap', 'some', 'Capitalized');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.capitalized(['Nope', 'not']);
=> false

is.palindrome(value:string, value:substring)

####Checks if the given string is palindrome. interfaces: not, all, any

is.palindrome('testset');
=> true

is.palindrome('nope');
=> false

is.not.palindrome('nope not palindrome');
=> true

is.not.palindrome('tt');
=> false

is.all.palindrome('testset', 'tt');
=> true

is.any.palindrome('Yeap', 'some', 'testset');
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.palindrome(['Nope', 'testset']);
=> false

Arithmetic checks

is.equal(value:any, value:any)

####Checks if the given values are equal. interfaces: not

is.equal(42, 40 + 2);
=> true

is.equal('yeap', 'yeap');
=> true

is.equal(true, true);
=> true

is.not.equal('yeap', 'nope');
=> true

is.even(value:number)

####Checks if the given value is even. interfaces: not, all, any

is.even(42);
=> true

is.not.even(41);
=> true

is.all.even(40, 42, 44);
=> true

is.any.even(39, 42, 43);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.even([40, 42, 43]);
=> false

is.odd(value:number)

####Checks if the given value is odd. interfaces: not, all, any

is.odd(41);
=> true

is.not.odd(42);
=> true

is.all.odd(39, 41, 43);
=> true

is.any.odd(39, 42, 44);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.odd([40, 42, 43]);
=> false

is.positive(value:number)

####Checks if the given value is positive. interfaces: not, all, any

is.positive(41);
=> true

is.not.positive(-42);
=> true

is.all.positive(39, 41, 43);
=> true

is.any.positive(-39, 42, -44);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.positive([40, 42, -43]);
=> false

is.negative(value:number)

####Checks if the given value is negative. interfaces: not, all, any

is.negative(-41);
=> true

is.not.negative(42);
=> true

is.all.negative(-39, -41, -43);
=> true

is.any.negative(-39, 42, 44);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.negative([40, 42, -43]);
=> false

is.above(value:number, min)

####Checks if the given value is above minimum value. interface: not

is.above(41, 30);
=> true

is.not.above(42, 50);
=> true

is.under(value:number, min)

####Checks if the given value is under maximum value. interface: not

is.under(30, 35);
=> true

is.not.under(42, 30);
=> true

is.within(value:number, min, max)

####Checks if the given value is within minimum and maximum values. interface: not

is.within(30, 20, 40);
=> true

is.not.within(40, 30, 35);
=> true

is.decimal(value:number)

####Checks if the given value is decimal. interfaces: not, all, any

is.decimal(41.5);
=> true

is.not.decimal(42);
=> true

is.all.decimal(39.5, 41.5, -43.5);
=> true

is.any.decimal(-39, 42.5, 44);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.decimal([40, 42.5, -43]);
=> false

is.integer(value:number)

####Checks if the given value is integer. interfaces: not, all, any

is.integer(41);
=> true

is.not.integer(42.5);
=> true

is.all.integer(39, 41, -43);
=> true

is.any.integer(-39, 42.5, 44);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.integer([40, 42.5, -43]);
=> false

is.finite(value:number)

####Checks if the given value is finite. interfaces: not, all, any

is.finite(41);
=> true

is.not.finite(42 / 0);
=> true

is.all.finite(39, 41, -43);
=> true

is.any.finite(-39, Infinity, 44);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.finite([Infinity, -Infinity, 42.5]);
=> false

is.infinite(value:number)

####Checks if the given value is infinite. interfaces: not, all, any

is.infinite(Infinity);
=> true

is.not.infinite(42);
=> true

is.all.infinite(Infinity, -Infinity, -43 / 0);
=> true

is.any.infinite(-39, Infinity, 44);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.infinite([Infinity, -Infinity, 42.5]);
=> false

Object checks

is.propertyCount(value:object, count)

####Checks if objects' property count is equal to given count. interface: not

is.propertyCount({this: 'is', 'sample': object}, 2);
=> true

is.propertyCount({this: 'is', 'sample': object}, 3);
=> false

is.not.propertyCount({}, 2);
=> true

is.propertyDefined(value:object, property)

####Checks if the given property is defined on object. interface: not

is.propertyDefined({yeap: 'yeap'}, 'yeap');
=> true

is.propertyDefined({yeap: 'yeap'}, 'nope');
=> false

is.not.propertyDefined({}, 'nope');
=> true

is.windowObject(value:window)

####Checks if the given object is window object. interfaces: not, all, any

is.windowObject(window);
=> true

is.windowObject({nope: 'nope'});
=> false

is.not.windowObject({});
=> true

is.all.windowObject(window, {nope: 'nope'});
=> false

is.any.windowObject(window, {nope: 'nope'});
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.windowObject([window, {nope: 'nope'}]);
=> false

is.domNode(value:object)

####Checks if the given object is a dom node. interfaces: not, all, any

var obj = document.createElement('div');
is.domNode(obj);
=> true

is.domNode({nope: 'nope'});
=> false

is.not.domNode({});
=> true

is.all.domNode(obj, obj);
=> true

is.any.domNode(obj, {nope: 'nope'});
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.domNode([obj, {nope: 'nope'}]);
=> false

Array checks

is.inArray(value:any, array)

####Checks if the given item is in array? interface: not

is.inArray(2, [1, 2, 3]);
=> true

is.inArray(4, [1, 2, 3]);
=> false

is.not.inArray(4, [1, 2, 3]);
=> true

is.sorted(value:array)

####Checks if the given array is sorted. interfaces: not, all, any

is.sorted([1, 2, 3]);
=> true

is.sorted([1, 2, 4, 3]);
=> false

is.not.sorted([5, 4, 3]);
=> true

is.all.sorted([1, 2], [3, 4]);
=> true

is.any.sorted([1, 2], [5, 4]);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.sorted([[1, 2], [5, 4]]);
=> false

Environment checks

####Environment checks are not available as node module.

is.ie(value:number)

####Checks if current browser is ie. Parameter is optional version number of browser. interface: not

is.ie();
=> true if current browser is ie

is.ie(6);
=> hopefully false

is.not.ie();
=> false if current browser is ie

is.chrome()

####Checks if current browser is chrome. interface: not

is.chrome();
=> true if current browser is chrome

is.not.chrome();
=> false if current browser is chrome

is.firefox()

####Checks if current browser is firefox. interface: not

is.firefox();
=> true if current browser is firefox

is.not.firefox();
=> false if current browser is firefox

is.opera()

####Checks if current browser is opera. interface: not

is.opera();
=> true if current browser is opera

is.not.opera();
=> false if current browser is opera

is.safari()

####Checks if current browser is safari. interface: not

is.safari();
=> true if current browser is safari

is.not.safari();
=> false if current browser is safari

is.ios()

####Checks if current device has ios. interface: not

is.ios();
=> true if current device is iPhone, iPad or iPod

is.not.ios();
=> true if current device is not iPhone, iPad or iPod

is.iphone()

####Checks if current device is iPhone. interface: not

is.iphone();
=> true if current device is iPhone

is.not.iphone();
=> true if current device is not iPhone

is.ipad()

####Checks if current device is iPad. interface: not

is.ipad();
=> true if current device is iPad

is.not.ipad();
=> true if current device is not iPad

is.ipod()

####Checks if current device is iPod. interface: not

is.ipod();
=> true if current device is iPod

is.not.ipod();
=> true if current device is not iPod

is.android()

####Checks if current device has Android. interface: not

is.android();
=> true if current device has Android OS

is.not.android();
=> true if current device has not Android OS

is.androidPhone()

####Checks if current device is Android phone. interface: not

is.androidPhone();
=> true if current device is Android phone

is.not.androidPhone();
=> true if current device is not Android phone

is.androidTablet()

####Checks if current device is Android tablet. interface: not

is.androidTablet();
=> true if current device is Android tablet

is.not.androidTablet();
=> true if current device is not Android tablet

is.blackberry()

####Checks if current device is Blackberry. interface: not

is.blackberry();
=> true if current device is Blackberry

is.not.blackberry();
=> true if current device is not Blackberry

is.windowsPhone()

####Checks if current device is Windows phone. interface: not

is.windowsPhone();
=> true if current device is Windows phone

is.not.windowsPhone();
=> true if current device is not Windows Phone

is.windowsTablet()

####Checks if current device is Windows tablet. interface: not

is.windowsTablet();
=> true if current device is Windows tablet

is.not.windowsTablet();
=> true if current device is not Windows tablet

is.windows()

####Checks if current OS is Windows. interface: not

is.windows();
=> true if current OS is Windows

is.not.windows();
=> true if current OS is not Windows

is.mac()

####Checks if current OS is Mac OS X. interface: not

is.mac();
=> true if current OS is Mac OS X

is.not.mac();
=> true if current OS is not Mac OS X

is.linux()

####Checks if current OS is linux. interface: not

is.linux();
=> true if current OS is linux

is.not.linux();
=> true if current OS is not linux

is.desktop()

####Checks if current device is desktop. interface: not

is.desktop();
=> true if current device is desktop

is.not.desktop();
=> true if current device is not desktop

is.mobile()

####Checks if current device is mobile. interface: not iPhone, iPod, Android Phone, Windows Phone, Blackberry.


is.mobile();
=> true if current device is mobile

is.not.mobile();
=> true if current device is not mobile

is.tablet()

####Checks if current device is tablet. interface: not iPad, Android Tablet, Windows Tablet


is.tablet();
=> true if current device is tablet

is.not.tablet();
=> true if current device is not tablet

is.online()

####Checks if current device is online. interface: not

is.online();
=> true if current device is online

is.not.online();
=> true if current device is not online

is.offline()

####Checks if current device is offline. interface: not

is.offline();
=> true if current device is offline

is.not.offline();
=> true if current device is not offline

Time checks

is.today(value:object)

####Checks if the given date object indicate today. interfaces: not, all, any

var today = new Date();
is.today(today);
=> true

var yesterday = new Date(new Date().setDate(new Date().getDate() - 1));
is.today(yesterday);
=> false

is.not.today(yesterday);
=> true

is.all.today(today, today);
=> true

is.any.today(today, yesterday);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.today([today, yesterday]);
=> false

is.yesterday(value:object)

####Checks if the given date object indicate yesterday. interfaces: not, all, any

var today = new Date();
is.yesterday(today);
=> false

var yesterday = new Date(new Date().setDate(new Date().getDate() - 1));
is.yesterday(yesterday);
=> true

is.not.yesterday(today);
=> true

is.all.yesterday(yesterday, today);
=> false

is.any.yesterday(today, yesterday);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.yesterday([today, yesterday]);
=> false

is.tomorrow(value:object)

####Checks if the given date object indicate tomorrow. interfaces: not, all, any

var today = new Date();
is.tomorrow(today);
=> false

var tomorrow = new Date(new Date().setDate(new Date().getDate() + 1));
is.tomorrow(tomorrow);
=> true

is.not.tomorrow(today);
=> true

is.all.tomorrow(tomorrow, today);
=> false

is.any.tomorrow(today, tomorrow);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.tomorrow([today, tomorrow]);
=> false

is.past(value:object)

####Checks if the given date object indicate past. interfaces: not, all, any

var yesterday = new Date(new Date().setDate(new Date().getDate() - 1));
var tomorrow = new Date(new Date().setDate(new Date().getDate() + 1));

is.past(yesterday);
=> true

is.past(tomorrow);
=> false

is.not.past(tomorrow);
=> true

is.all.past(tomorrow, yesterday);
=> false

is.any.past(yesterday, tomorrow);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.past([yesterday, tomorrow]);
=> false

is.future(value:object)

####Checks if the given date object indicate future. interfaces: not, all, any

var yesterday = new Date(new Date().setDate(new Date().getDate() - 1));
var tomorrow = new Date(new Date().setDate(new Date().getDate() + 1));

is.future(yesterday);
=> false

is.future(tomorrow);
=> true

is.not.future(yesterday);
=> true

is.all.future(tomorrow, yesterday);
=> false

is.any.future(yesterday, tomorrow);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.future([yesterday, tomorrow]);
=> false

is.day(value:object, dayString)

####Checks if the given date objects' day equal given dayString parameter. interface: not

var mondayObj = new Date('01/26/2015');
var tuesdayObj = new Date('01/27/2015');
is.day(mondayObj, 'monday');
=> true

is.day(mondayObj, 'tuesday');
=> false

is.not.day(mondayObj, 'tuesday');
=> true

is.month(value:object, monthString)

####Checks if the given date objects' month equal given monthString parameter. interface: not

var januaryObj = new Date('01/26/2015');
var februaryObj = new Date('02/26/2015');
is.month(januaryObj, 'january');
=> true

is.month(februaryObj, 'january');
=> false

is.not.month(februaryObj, 'january');
=> true

is.year(value:object, yearNumber)

####Checks if the given date objects' year equal given yearNumber parameter. interface: not

var year2015 = new Date('01/26/2015');
var year2016 = new Date('01/26/2016');
is.year(year2015, 2015);
=> true

is.year(year2016, 2015);
=> false

is.not.year(year2016, 2015);
=> true

is.leapYear(value:number)

####Checks if the given year number is a leap year interfaces: not, all, any

is.leapYear(2016);
=> true

is.leapYear(2015);
=> false

is.not.leapYear(2015);
=> true

is.all.leapYear(2015, 2016);
=> false

is.any.leapYear(2015, 2016);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.leapYear([2016, 2080]);
=> true

is.weekend(value:object)

####Checks if the given date objects' day is weekend. interfaces: not, all, any

var monday = new Date('01/26/2015');
var sunday = new Date('01/25/2015');
var saturday = new Date('01/24/2015');
is.weekend(sunday);
=> true

is.weekend(monday);
=> false

is.not.weekend(monday);
=> true

is.all.weekend(sunday, saturday);
=> true

is.any.weekend(sunday, saturday, monday);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.weekend([sunday, saturday, monday]);
=> false

is.weekday(value:object)

####Checks if the given date objects' day is weekday. interfaces: not, all, any

var monday = new Date('01/26/2015');
var sunday = new Date('01/25/2015');
var saturday = new Date('01/24/2015');
is.weekday(monday);
=> true

is.weekday(sunday);
=> false

is.not.weekday(sunday);
=> true

is.all.weekday(monday, saturday);
=> false

is.any.weekday(sunday, saturday, monday);
=> true

// 'all' and 'any' interfaces can also take array parameter
is.all.weekday([sunday, saturday, monday]);
=> false

is.inDateRange(value:object, startObject, endObject)

####Checks if date is within given range. interface: not

var saturday = new Date('01/24/2015');
var sunday = new Date('01/25/2015');
var monday = new Date('01/26/2015');
is.inDateRange(sunday, saturday, monday);
=> true

is.inDateRange(saturday, sunday, monday);
=> false

is.not.inDateRange(saturday, sunday, monday);
=> true

is.inLastWeek(value:object)

####Checks if the given date is between now and 7 days ago. interface: not

var twoDaysAgo = new Date(new Date().setDate(new Date().getDate() - 2));
var nineDaysAgo = new Date(new Date().setDate(new Date().getDate() - 9));
is.inLastWeek(twoDaysAgo);
=> true

is.inLastWeek(nineDaysAgo);
=> false

is.not.inLastWeek(nineDaysAgo);
=> true

is.inLastMonth(value:object)

####Checks if the given date is between now and a month ago. interface: not

var tenDaysAgo = new Date(new Date().setDate(new Date().getDate() - 10));
var fortyDaysAgo = new Date(new Date().setDate(new Date().getDate() - 40));
is.inLastMonth(tenDaysAgo);
=> true

is.inLastMonth(fortyDaysAgo);
=> false

is.not.inLastMonth(fortyDaysAgo);
=> true

is.inLastYear(value:object)

####Checks if the given date is between now and a year ago. interface: not

var twoMonthsAgo = new Date(new Date().setMonth(new Date().getMonth() - 2));
var thirteenMonthsAgo = new Date(new Date().setMonth(new Date().getMonth() - 13));
is.inLastYear(twoMonthsAgo);
=> true

is.inLastYear(thirteenMonthsAgo);
=> false

is.not.inLastYear(thirteenMonthsAgo);
=> true

is.inNextWeek(value:object)

####Checks if the given date is between now and 7 days later. interface: not

var twoDaysLater = new Date(new Date().setDate(new Date().getDate() + 2));
var nineDaysLater = new Date(new Date().setDate(new Date().getDate() + 9));
is.inNextWeek(twoDaysLater);
=> true

is.inNextWeek(nineDaysLater);
=> false

is.not.inNextWeek(nineDaysLater);
=> true

is.inNextMonth(value:object)

####Checks if the given date is between now and a month later. interface: not

var tenDaysLater = new Date(new Date().setDate(new Date().getDate() + 10));
var fortyDaysLater = new Date(new Date().setDate(new Date().getDate() + 40));
is.inNextMonth(tenDaysLater);
=> true

is.inNextMonth(fortyDaysLater);
=> false

is.not.inNextMonth(fortyDaysLater);
=> true

is.inNextYear(value:object)

####Checks if the given date is between now and a year later. interface: not

var twoMonthsLater = new Date(new Date().setMonth(new Date().getMonth() + 2));
var thirteenMonthsLater = new Date(new Date().setMonth(new Date().getMonth() + 13));
is.inNextYear(twoMonthsLater);
=> true

is.inNextYear(thirteenMonthsLater);
=> false

is.not.inNextYear(thirteenMonthsLater);
=> true

is.quarterOfYear(value:object, quarterNumber)

####Checks if the given date is in the parameter quarter. interface: not

var firstQuarter = new Date('01/26/2015');
var secondQuarter = new Date('05/26/2015');
is.quarterOfYear(firstQuarter, 1);
=> true

is.quarterOfYear(secondQuarter, 1);
=> false

is.not.quarterOfYear(secondQuarter, 1);
=> true

is.dayLightSavingTime(value:object, quarterNumber)

####Checks if the given date is in daylight saving time. interface: not

// For Turkey Time Zone
var january1 = new Date('01/01/2015');
var june1 = new Date('06/01/2015');

is.dayLightSavingTime(june1);
=> true

is.dayLightSavingTime(january1);
=> false

is.not.dayLightSavingTime(january1);
=> true

Configuration methods

is.setRegexp(value:RegExp, regexpString)

Override RegExps if you think they suck.

is.url('https://www.duckduckgo.com');
=> true

is.setRegexp(/quack/, 'url');
is.url('quack');
=> true

is.setNamespace()

Change namespace of library to prevent name collisions.

var customName = is.setNamespace();
customName.odd(3);
=> true

FAQs

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Package last updated on 11 Feb 2015

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is_js