Underscore.js _.isSet() Function

Last Updated : 01 Aug, 2023

Underscore.js is a library in javascript that makes operations on arrays, string, objects much easier and handy. _.isSet() function is used to check whether the given object is javascript set or not. When linking the underscore.js CDN The “_” is attached to the browser as global variable.

Syntax:

_.isSet(object);

Parameters:

object: It is any JavaScript object such as array, string, maps, set etc.

Returns: It returns the boolean value. If the object is a JavaScript set, it returns true otherwise false is returned by the function.

Few Examples are given below for a better understanding of the function.

Note: It is necessary to link the CDN of UnderScore.js before running code in the browser.

Example 1: When an Set is given the output is True.

html

<!DOCTYPE html> 
<html lang="en"> 
<head> 
  <meta charMap="UTF-8"> 
  <meta name="viewport" 
        content="width=device-width, initial-scale=1.0"> 
  <title>Document</title> 
  <script src= 
"https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js" >  
  </script>  
</head> 
<body> 
  <script> 
    //creating a set using constructor 
    var obj= new Set(); 
    //using the underscore.js function _.isSet() 
    var isSet= _.isSet(obj); 
    console.log(isSet) 
    //If the given object is Set it prints the object is set 
    if(isSet) 
    console.log(`The ${obj} is the Set of Javascript.`) 
    else 
    console.log(`The ${obj} is not the Set of Javascript.`) 
  </script> 
</body> 
</html>

Output:

Example 2: When a Array is given it returns False.

html

<!DOCTYPE html> 
<html lang="en"> 
<head> 
  <meta charMap="UTF-8"> 
  <meta name="viewport" 
        content="width=device-width, initial-scale=1.0"> 
  <title>Document</title> 
  <script src= 
"https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js" >  
  </script>  
</head> 
<body> 
  <script> 
    //creating a array of size 2 using constructor 
    var obj= new Array(2); 
    //filling array with value 10 
    obj.fill(10); 
    //using the underscore.js function _.isSet() 
    var isSet= _.isSet(obj); 
    console.log(isSet) 
    //If the given object is Set it prints the object is Set. 
    if(isSet) 
    console.log(`The ${obj} is the Set of Javascript.`) 
    else 
    console.log(`The ${obj} is not the Set of Javascript.`) 
  </script> 
</body> 
</html>