Open In App

Node.js util.types.isAsyncFunction() Method

Improve
Improve
Like Article
Like
Save
Share
Report

The util.types.isAsyncFunction() method is an inbuilt application programming interface of the util module which is used to type check for asynchronous functions in the node.js.

Syntax: 

util.types.isAsyncFunction( value )

Parameters: This method accepts a single parameter as mentioned above and described below: 

  • value: It is a required parameter that holds any data type.

Return Value: It returns a boolean value, TRUE if the value is an async function from the perspective of the JavaScript engine, FALSE otherwise.

The below examples illustrate the use of util.types.isAsyncFunction() method in Node.js:

Example 1: 

javascript




// Node.js program to demonstrate the  
// util.types.isAsyncFunction() Method
 
// Allocating util module
const util = require('util');
 
// Functions to be passed as parameter of
// util.types.isAsyncFunction() method
let f2 = async function function2() { }
let f1 = function function1() { }
 
// Printing the returned value from
// util.types.isAsyncFunction() method
console.log(util.types.isAsyncFunction(f2));
console.log(util.types.isAsyncFunction(f1));


Output: 

true
false

Example 2: 

javascript




// Node.js program to demonstrate the
// util.types.isAsyncFunction() Method
 
// Allocating util module
const util = require('util');
 
// Functions to be passed as parameter
const f2 = async function function2() { }
const f1 = function function1() { }
 
// Calling util.types.isAsyncFunction() method
if (util.types.isAsyncFunction(f2))
    console.log("The passed value is an Async function.");
else
    console.log("The passed value is not an Async function");
 
if (util.types.isAsyncFunction(f1))
    console.log("The passed value is an Async function.");
else
    console.log("The passed value is not an Async function");


Output: 

The passed value is an Async function.
The passed value is not an Async function

Note: The above program will compile and run by using the node filename.js command.

Reference: https://nodejs.org/api/util.html#util_util_types_isasyncfunction_value



Last Updated : 03 Apr, 2023
Like Article
Save Article
Previous
Next
Share your thoughts in the comments
Similar Reads