Underscore.js _.isSymbol() Function

Last Updated : 25 Nov, 2021

Underscore.js is a library in javascript that makes operations on arrays, string, objects much easier and handy. _.isSymbol() function is used to check whether the given object is javascript Symbol Object or not.

Note: It is very necessary to link the underscore CDN before going and using underscore functions in the browser. When linking the underscore.js CDN The “_” is attached to the browser as global variable.

Syntax:

_.isSymbol(object);

Parameters: It takes only one parameter i.e object.

Returns: It returns the boolean value. If the object is a Symbol object of javascript it returns true otherwise false is returned by the function.

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

Example 1: When symbol is created with some value.

HTML

<!DOCTYPE html>  
<html>  
  <head>  
    <script src =   
"https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js" >  
    </script>  
   </head>  
  <body> 
    <script> 
      //creating new symbol from symbol object 
      let e=Symbol("some symbol") 
      let ans=_.isSymbol(e) 
      console.log("symbol is :", e) 
      console.log(_.isSymbol(e)) 
      if(ans) 
      console.log("It is the javascript Symbol Object") 
      else 
      console.log("It is the not javascript Symbol Object") 
    </script> 
  </body>  
</html>

Output:

Example 2: When a symbol is created with no given object

HTML

<!DOCTYPE html>  
<html>  
  <head>  
    <script src =   
"https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js" >  
    </script>  
   </head>  
  <body> 
    <script> 
      //creating new symbol from symbol object 
      let e=Symbol() 
      let ans=_.isSymbol(e) 
      //printing the symbol 
      console.log("symbol is :", e.valueOf(e)) 
      //printing true if this is the symbol else false 
      console.log(_.isSymbol(e)) 
      if(ans) 
      console.log("It is the javascript Symbol Object") 
      else 
      console.log("It is the not javascript Symbol Object") 
    </script> 
  </body>  
</html>

Output:

Example 3: When a given object is the string.

HTML

<!DOCTYPE html>  
<html>  
  <head>  
    <script src =   
"https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.9.1/underscore-min.js" >  
    </script>  
   </head>  
  <body> 
    <script> 
      //creating new string 
      let e="geeksforgeeks" 
      let ans=_.isSymbol(e) 
      //printing the symbol 
      console.log("symbol is :", e.valueOf(e)) 
      //printing true if this is the symbol else false 
      console.log(_.isSymbol(e)) 
      if(ans) 
      console.log("It is the javascript Symbol Object") 
      else 
      console.log("It is the not javascript Symbol Object") 
    </script> 
  </body>  
</html>