Node.js assert() Method
Example
If an expression evaluates to 0 or false, an error is thrown and the program is terminated:
var assert = require('assert');
assert(50 > 70);
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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.
Syntax
The syntax for including the assert module in your application:
assert(expression, message);
Parameter Values
Parameter | Description |
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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 |
Technical Details
Return Value: | None |
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Node.js Version: | 0.5.9 |
More Examples
Example
Using the message parameter:
var assert = require('assert');
assert(50 > 70, "My message goes here");
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Example
The assert method also throws an error if the expression evaluates to 0:
var assert = require('assert');
assert(50 - 50);
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