Node.js assert() Method

If an expression evaluates to 0 or false, an error is thrown and the program is terminated:

var assert = require('assert');
assert(50 > 70);

Definition and Usage

The assert() method tests if a given expression is true or not.

If the expression evaluates to 0, or false, an assertion failure is being caused, and the program is terminated.

The assert() method is an alias of the assert.ok() method.

The syntax for including the assert module in your application:

assert(expression, message);

Parameter	Description
expression	Required. Specifies an expression to be evaluated
message	Optional. Specifies the error message to be assigned to the AssertionError. If omitted, a default message is assigned

Return Value:	None
Node.js Version:	0.5.9

Using the message parameter:

var assert = require('assert');
assert(50 > 70, "My message goes here");

The assert method also throws an error if the expression evaluates to 0:

var assert = require('assert');
assert(50 - 50);