Node.js process.throwDeprecation Property

The process.throwDeprecation property is an inbuilt application programming interface of the process module which is used to indicates whether the –throw-deprecation flag is set on the current Node.js process. process.throwDeprecation is mutable, so whether or not deprecation warnings result in errors may be altered at runtime.

Syntax:

process.throwDeprecation

Return Value: This property indicates whether the –throw-deprecation flag is set on the current Node.js process.

Below examples illustrate the use of process.throwDeprecation property in Node.js:

Example 1:

Javascript

// Node.js program to demonstrate the
// process.throwDeprecation Property

// Include process module
const process = require('process');

// Printing process.throwDeprecation
// property value
console.log(process.throwDeprecation);

Command to run: node –throw-deprecation hello.js

Output 1:

true

Command to run: node hello.js

Output 2:

undefined

Example 2:

Javascript

// Node.js program to demonstrate the
// process.throwDeprecation Property

// Include process module
const process = require('process');

// Instance Properties
process.throwDeprecation = false;

// Printing process.throwDeprecation
// property value
console.log(process.throwDeprecation);

// Instance Properties
process.throwDeprecation = true;

// Printing process.throwDeprecation
// property value
console.log(process.throwDeprecation);

Command to run: node –throw-deprecation hello.js

Output 1:

true
true

Command to run: node hello.js

Output 2:

false
true

Reference: https://nodejs.org/api/process.html#process_process_throwdeprecation