Supportive Is

A very lightweight library to validate different things

Installation

npm i @mongez/supportive-is

Or using Yarn

yarn add @mongez/supportive-is

Usage

There are many data types here to be checked, but firstly let's import the package

import Is from '@mongez/supportive-is';

// use it

Primitives

We've tons of primitives to be checked, here are some of them.

Is.primitive

Check if the given value is a string, number, boolean, null, undefined or symbol

console.log(Is.primitive('hello')); // true
console.log(Is.primitive(22.5)); // true
console.log(Is.primitive(false)); // true
console.log(Is.primitive(null)); // true
console.log(Is.primitive(Symbol('SymbolKey'))); // true
console.log(Is.primitive(undefined)); // true
console.log(Is.primitive([])); // false
console.log(Is.primitive({})); // false

Is.scalar

Check if the given value is a string, number or boolean

console.log(Is.scalar('hello')); // true
console.log(Is.scalar(22.5)); // true
console.log(Is.scalar(false)); // true
console.log(Is.scalar(null)); // false
console.log(Is.scalar(undefined)); // false
console.log(Is.scalar([])); // false
console.log(Is.scalar({})); // false

Is.json

Check if the given value string is a valid json format

let value = '{"name":"Hasan","job":"Software Engineer"}';
console.log(Is.json(value)); // true

Is.null

Check if the given value is null

let name = null;
console.log(Is.null(name)); // true

name = undefined;
console.log(Is.null(name)); // false

Is.undefined

Check if the given value is undefined

let name = 'Hasan';
console.log(Is.undefined(name)); // false

let myVar; // any declared variable without a value will be treated as undefined
console.log(Is.undefined(myVar)); // true

let age = undefined;
console.log(Is.undefined(age)); // true

Is.numeric

Check if the given value is a number whether if its data type is String or Number

let numberInt = 12;
console.log(Is.numeric(numberInt)); // true

let numberFloat = 12.55;
console.log(Is.numeric(numberFloat)); // true

let numberWrittenInString = '99';
console.log(Is.numeric(numberWrittenInString)); // true

let floatWrittenInString = '99.99';
console.log(Is.numeric(floatWrittenInString)); // true

Is.number

Check if the given value is a number whether if its data type is Number

let numberInt = 12;
console.log(Is.number(numberInt)); // true

let numberFloat = 12.55;

console.log(Is.number(numberFloat)); // true

let numberWrittenInString = '99';

console.log(Is.number(numberWrittenInString)); // false

let floatWrittenInString = '99.99';

console.log(Is.number(floatWrittenInString)); // false

The major difference between Is.numeric and Is.number is that Is.numeric will return true if the given value is a string that contains a number

Is.int

Check if the given value is an integer and its data type is number

let number = 12;
console.log(Is.int(numberInt)); // true

let numberInString = '12';
console.log(Is.int(numberInString)); // false

Is.float

Check if the given value is a float number and its data type is number

let number = 921;
console.log(Is.float(number)); // true

number = 82.42;
console.log(Is.float(number)); // true

let numberInString = '12';
console.log(Is.float(numberInString)); // false

Is.string

Check if the given value is string

console.log(Is.string('this is a string')); // true

Is.bool

Check if the given value is boolean

console.log(Is.bool(true)); // true
console.log(Is.bool(false)); // true

Is.boolean is an alias for Is.bool

Is.symbol

Check if the given value is a symbol

let mySymbol = Symbol('mySymbol');

console.log(Is.symbol(mySymbol)); // true

Is.NaN

Check if the given value is Not a Number This method works exactly same as isNaN as it is already implementing it xD.

let number = 76; // number int
console.log(Is.NaN(number)); // false

number = '76'; // string
console.log(Is.NaN(number)); // true

Is.regex

Check if the given value is a regular expression

let regex = /hello/;

console.log(Is.regex(regex)); // true

let regexString = '/hello/';

console.log(Is.regex(regexString)); // false

let regexObject = new RegExp('hello');

console.log(Is.regex(regexObject)); // true

Objects, Classes And Arrays

Now let's check some objects.

Is.object

Check if the given value is an object

Any type of objects will be validated as true no matter its object type

Arrays are types of objects so any passed array will be validated as true null values are considered objects in javascript, but it will be validated as false if provided.

let myObject = {};
console.log(Is.object(myObject)); // true

class myClass {}
let anotherObject = new myClass;
console.log(Is.object(myObject)); // true

let myArray = [];
console.log(Is.object(myArray)); // true

console.log(Is.object(null)); // false

// to check if the given value is an object but not an array
//you must mix between Is.object AND Is.array to avoid an array
if (Is.object(myVar) && ! Is.array(myVar)) {
    // do something with that object
}

Is.plainObject

Check if the given value is a plain javascript object

// plain objects
let myObject = {};
console.log(Is.plainObject(myObject)); // true

// classes
class myClass {}
let anotherObject = new myClass;

console.log(Is.plainObject(myObject)); // false

// arrays
let myArray = [];

console.log(Is.plainObject(myArray)); // false

// null value
console.log(Is.plainObject(null)); // false

Is.a

Check if the given value is an instance of the given class

class myClass {}

let myObject = new myClass;

console.log(Is.a(myObject, myClass)); // true

Is.array

Check if the given value is an array

let myArray = [4 , 'hello', 9];
console.log(Is.array(myArray)); // true

Is.iterable

Check if the given value is iterable

let myArray = [1, 2, 3];

console.log(Is.iterable(myArray)); // true

let myObject = {a: 1, b: 2, c: 3};

console.log(Is.iterable(myObject)); // true

let myString = 'hello';

console.log(Is.iterable(myString)); // true

let myNumber = 123;

console.log(Is.iterable(myNumber)); // false

let myBoolean = true;

console.log(Is.iterable(myBoolean)); // false

let myFunction = function() {};

console.log(Is.iterable(myFunction)); // false

let myNull = null;

console.log(Is.iterable(myNull)); // false

let myUndefined = undefined;

console.log(Is.iterable(myUndefined)); // false

It works fine as well with any class that implements the Symbol.iterator method

class myClass {
    *[Symbol.iterator]() {
        yield 1;
        yield 2;
        yield 3;
    }
}

let myObject = new myClass();

console.log(Is.iterable(myObject)); // true

Is.empty

Check if the given value is empty.

This is a kind of smart method that will validate the given value whether it is empty or not based on its type

// undefined values are considered empty
let value = undefined;
console.log(Is.empty(value)); // true

// null values are considered empty
value = null;
console.log(Is.empty(value)); // true

// Also any objects with no values are considered empty
value = {};
console.log(Is.empty(value)); // true

value.name = 'Hasan';
console.log(Is.empty(value)); // false

// Arrays
value = [];
console.log(Is.empty(value)); // true

value.push(12);
console.log(Is.empty(value)); // false

// The `Zero` is not considered as empty value
value = 0;
console.log(Is.empty(value)); // false

Functions And Generators

Is.function

Check if the given value is a function

function sum(x, y) {
    return x + y;
}

// you must pass the function name not the function call
console.log(Is.function(sum)); // true

// if you passed the function call it will be not a function in this situation
console.log(Is.function(sum(2, 3))); // false

Is.callable is an alias for Is.function Is.fn is an alias for Is.function

Is.generator

Check if the given value is a generator

function* myGenerator() {
    yield 1;
    yield 2;
    yield 3;
}

let myGeneratorObject = myGenerator();

console.log(Is.generator(myGeneratorObject)); // true

Is.native

Check if the given value is a native javascript function

let myFunction = function() {
    return 'hello world';
};

console.log(Is.native(myFunction)); // false

console.log(Is.native(Math.random)); // true

Misc

Is.url

Check if the given value is a valid url

let url = 'google.com';
console.log(Is.url(url)); // true

url = 'https://google.com';
console.log(Is.url(url)); // true

url = 'www.google.com';
console.log(Is.url(url)); // true
url = 'www.google.com:8080';
console.log(Is.url(url)); // true

url = 'www.google.com?q=hello+world';
console.log(Is.url(url)); // true

let url = 'google';
console.log(Is.url(url)); // false

Is.email

Check if the given value string is a valid email

let myEmail = 'hassanzohdy@gmail.com';
console.log(Is.email(myEmail)); // true

Is.date

Check if the given value is a date

let myDate = new Date();

console.log(Is.date(myDate)); // true

Is.promise

Check if the given value is a promise

let myPromise = new Promise((resolve, reject) => {
    resolve('hello world');
});

console.log(Is.promise(myPromise)); // true

Is.error

Check if the given value is an error

let myError = new Error('my error');

console.log(Is.error(myError)); // true

DOM & Browser

Is.dom

Check if the given value is a dom element

Dom Elements are objects of HTMLElement, so any html element will be validated as true, something like document.body document and window are not validated as true as they are not part of the html elements

console.log(Is.dom(document)); // false

console.log(Is.dom(document.body)); // true

Is.form

Check if the given value is a form element

let myForm = document.querySelector('form');

console.log(Is.form(myForm)); // true

Is.formElement is an alias for Is.form

Is.formData

Check if the given value is a form data

let myFormData = new FormData();

console.log(Is.formData(myFormData)); // true

Is.browser

Check if current browser matches the given name

console.log(Is.browser('chrome'));
console.log(Is.browser('firefox'));
console.log(Is.browser('safari'));
console.log(Is.browser('opera'));
console.log(Is.browser('edge'));
console.log(Is.browser('ie'));

Is.validHtmlId

Check if the given value is a valid html id

let id = 'myId';

console.log(Is.validHtmlId(id)); // true

id = 'myId-1';

console.log(Is.validHtmlId(id)); // true

id = 'myId-1-1';

console.log(Is.validHtmlId(id)); // true

id = 'myId-1-';

console.log(Is.validHtmlId(id)); // false

Is.mobile.*

Check if current visitor is browsing from a sort-of mobile

this property contains set of methods

// To check if user is browsing from an android device
if (Is.mobile.android()) {
    // do something
}

// To check if  user is browsing from an ios device
if (Is.mobile.ios()) {
    // do something
}

// To check if  user is browsing from an iphone
if (Is.mobile.iphone()) {
    // do something
}

// To check if  user is browsing from an ipad
if (Is.mobile.ipad()) {
    // do something
}

// To check if  user is browsing from an ipod
if (Is.mobile.ipod()) {
    // do something
}

// To check if  user is browsing from a windows mobile
if (Is.mobile.windows()) {
    // do something
}

// To check if user is browsing from any type of mobile
if (Is.mobile.any()) {
    // do something
}

Is.desktop

Check if current visitor is browsing from a desktop device

Please note that any non mobile type will be considered as desktop.

if (! Is.desktop()) {
    // do something
}

Is.enabled.*

Check for variant data that are enabled in the browser

console.log(Is.enabled.cookies());
console.log(Is.enabled.localStorage());
console.log(Is.enabled.sessionStorage());
console.log(Is.enabled.indexedDB());
console.log(Is.enabled.webWorkers()); 
console.log(Is.enabled.serviceWorkers());
console.log(Is.enabled.notifications());
console.log(Is.enabled.pushNotifications());
console.log(Is.enabled.geoLocation()); // also geolocation is an alias (with lower L)
console.log(Is.enabled.webRTC());
console.log(Is.enabled.webAudio()); 
console.log(Is.enabled.microphone());
console.log(Is.enabled.camera());
console.log(Is.enabled.speechRecognition());
console.log(Is.enabled.speechSynthesis());
console.log(Is.enabled.fullScreen()); // also fullscreen is an alias (with lower S)
console.log(Is.enabled.vibration());
console.log(Is.enabled.touch());
console.log(Is.enabled.battery());
console.log(Is.enabled.fetch());
console.log(Is.enabled.history());
console.log(Is.enabled.darkMode()); // will validate prefers-color-scheme media query (dark mode)
console.log(Is.enabled.lightMode()); // will validate prefers-color-scheme media query (light mode)
console.log(Is.enabled.animation());
console.log(Is.enabled.transition());

Tests

To run tests, run the following command

npm run test

yarn test

Change Log

1.0.7 (11 Oct 2022)
- Added tests
- Enhanced Documentation
- Added more methods