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    Micro check library
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    is.js

    JS.ORG

    This is a general-purpose check library.

    • No dependencies
    • AMD, Node & browser ready

    Usage:

    Node.js:

    npm install is_js
    

    Bower:

    bower install is_js
    

    Build:

    npm run build
    

    Test:

    npm test
    

    Contributing:

    Thanks for considering to contribute. Check here

    Contributors:

    Many thanks to our contributors: https://github.com/arasatasaygin/is.js/graphs/contributors

    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.domNode(value:any)

    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
    

    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.number(NaN);
    => false
    
    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 returning 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.json(value:any)

    Checks if the given value type is pure json object.

    interfaces: not, all, any

    is.json({foo: 'bar'});
    => true
    
    // functions are returning as false
    is.json(toString);
    => false
    
    is.not.json([]);
    => true
    
    is.all.json({}, 1);
    => false
    
    is.any.json({}, 2);
    => true
    
    // 'all' and 'any' interfaces can also take array parameter
    is.all.json([{}, {foo: 'bar'}]);
    => 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, other: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
    

    is.windowObject(value:any)

    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
    

    Presence checks

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

    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('10-21-2012');
    => 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('017907890');
    => true
    
    is.socialSecurityNumber('123');
    => false
    
    is.not.socialSecurityNumber('123');
    => true
    
    is.all.socialSecurityNumber('017-90-7890', '123');
    => false
    
    is.any.socialSecurityNumber('017907890', '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('0xf0f0f0');
    => true
    
    is.hexadecimal(2.5);
    => false
    
    is.not.hexadecimal('string');
    => true
    
    is.all.hexadecimal('ff', 'f50');
    => true
    
    is.any.hexadecimal('0xff5500', 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:any)

    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:any)

    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:any)

    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, target:string)

    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, target:string)

    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, target:string)

    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)

    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)

    Checks if the given string is palindrome.

    interfaces: not, all, any

    is.palindrome('testset');
    => true
    
    is.palindrome('A man, a plan, a canal - Panama!');
    => 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, other: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:number)

    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, max:number)

    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:number, max:number)

    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:number)

    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:string)

    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
    

    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, sign:string)

    Checks if the given array is sorted. Sign is optional parameter.

    interfaces: not, all, any

    is.sorted([1, 2, 3]);
    => true
    
    is.sorted([1, 2, 4, 3]);
    => false
    
    is.sorted([1, 1, 2, 2], '>=');
    => true
    
    is.sorted([1, 2, 3, 4], '>');
    => true
    
    is.sorted([4, 3, 3, 1], '<=');
    => true
    
    is.sorted([4, 3, 2, 1], '<');
    => true
    
    is.sorted([1, 2, 3, 3], '>');
    => false
    
    is.not.sorted([5, 4, 3]);
    => true
    
    is.not.sorted([5, 4, 3], '<');
    => false
    
    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(range:number|string)

    Checks if current browser is ie. Parameter is optional version range (or number) of browser.

    interface: not

    is.ie();
    => true if current browser is ie
    
    is.not.ie();
    => false if current browser is ie
    
    // also supports version number
    is.ie(10);
    => true if current version of ie is 10
    
    is.ie('>=10');
    => true if current version of ie is greater than or equal to 10
    
    is.not.ie('<9');
    => true if current version of ie is not less than 9
    

    is.chrome(range:number|string)

    Checks if current browser is chrome. Parameter is optional version range (or number) of browser.

    interface: not

    is.chrome();
    => true if current browser is chrome
    
    is.not.chrome();
    => false if current browser is chrome
    
    // also supports version number
    is.chrome(50);
    => true if current version of chrome is 50
    
    is.chrome('>=40');
    => true if current version of chrome is greater than or equal to 40
    
    is.not.chrome('<30');
    => true if current version of chrome is not less than 30
    

    is.firefox(range:number|string)

    Checks if current browser is firefox. Parameter is optional version range (or number) of browser.

    interface: not

    is.firefox();
    => true if current browser is firefox
    
    is.not.firefox();
    => false if current browser is firefox
    
    // also supports version number
    is.firefox(41);
    => true if current version of firefox is 41
    
    is.firefox('>=40');
    => true if current version of firefox is greater than or equal to 40
    
    is.not.firefox('<30');
    => true if current version of firefox is not less than 30
    

    is.edge(range:number|string)

    Checks if current browser is edge. Parameter is optional version range (or number) of browser.

    interface: not

    is.edge();
    => true if current browser is edge
    
    is.not.edge();
    => false if current browser is edge
    
    // also supports version number
    is.edge(13);
    => true if current version of edge is 13
    
    is.edge('>=12');
    => true if current version of edge is greater than or equal to 12
    
    is.not.edge('<13');
    => true if current version of edge is not less than 13
    

    is.opera(range:number|string)

    Checks if current browser is opera. Parameter is optional version range (or number) of browser.

    interface: not

    is.opera();
    => true if current browser is opera
    
    is.not.opera();
    => false if current browser is opera
    
    // also supports version number
    is.opera(36);
    => true if current version of opera is 36
    
    is.opera('>=35');
    => true if current version of opera is greater than or equal to 35
    
    is.not.opera('<20');
    => true if current version of opera is not less than 20
    

    is.safari(range:number|string)

    Checks if current browser is safari. Parameter is optional version range (or number) of browser.

    interface: not

    is.safari();
    => true if current browser is safari
    
    is.not.safari();
    => false if current browser is safari
    
    // also supports version number
    is.safari(9);
    => true if current version of safari is 9
    
    is.safari('>=8');
    => true if current version of safari is greater than or equal to 8
    
    is.not.safari('<7');
    => true if current version of safari is not less than 7
    

    is.phantom(range:number|string)

    Checks if current browser is phantomjs. Parameter is optional version range (or number) of browser.

    interface: not

    is.phantom();
    => true if current browser is phantomjs
    
    is.not.phantom();
    => false if current browser is phantomjs
    
    // also supports version number
    is.phantom(2);
    => true if current version of phantom is 2
    
    is.phantom('>=1');
    => true if current version of phantomjs is greater than or equal to 1
    
    is.not.phantom('<2');
    => true if current version of phantomjs is not less than 2
    

    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(range:number|string)

    Checks if current device is iPhone. Parameter is optional version range (or number) of browser.

    interface: not

    is.iphone();
    => true if current device is iPhone
    
    is.not.iphone();
    => true if current device is not iPhone
    
    // also supports version number
    is.iphone(9);
    => true if current version of iPhone is 9
    
    is.iphone('>=7');
    => true if current version of iPhone is greater than or equal to 7
    
    is.not.iphone('<8');
    => true if current version of iPhone is not less than 8
    

    is.ipad(range:number|string)

    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
    
    // also supports version number
    is.ipad(9);
    => true if current version of iPad is 9
    
    is.ipad('>=7');
    => true if current version of iPad is greater than or equal to 7
    
    is.not.ipad('<8');
    => true if current version of iPad is not less than 8
    

    is.ipod(range:number|string)

    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
    
    // also supports version number
    is.ipod(7);
    => true if current version of iPod is 7
    
    is.ipod('>=5');
    => true if current version of iPod is greater than or equal to 5
    
    is.not.ipod('<5');
    => true if current version of iPod is not less than 5
    

    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
    

    is.touchDevice()

    Checks if current device supports touch.

    interface: not

    is.touchDevice();
    => true if current device supports touch
    
    is.not.touchDevice();
    => true if current device does not support touch
    

    Time checks

    is.today(value:date)

    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:date)

    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:date)

    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:date)

    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:date)

    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:date, day:string)

    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:date, month:string)

    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:date, year:number)

    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:date)

    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:date)

    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:date, start:date, end:date)

    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:date)

    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:date)

    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:date)

    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:date)

    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:date)

    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:date)

    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:date, quarter:number)

    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:date)

    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.setNamespace()

    Change namespace of library to prevent name collisions.

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

    is.setRegexp(value:regexp, name:string)

    Override RegExps if you think they suck.

    is.url('https://www.duckduckgo.com');
    => true
    
    is.setRegexp(/quack/, 'url');
    is.url('quack');
    => true
    
    Show All