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var validateIoNan = require("")

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Validates if a value is NaN.


NPM version Build Status Coverage Status Dependencies

Validates if a value is NaN.


$ npm install

For use in the browser, use browserify.


var isnan = require( '' );

isnan( value )

Validates if a value is NaN.

var value = NaN;

var bool = isnan( value );
// returns true

Note: the method first validates that a value is numeric before validating if a value is NaN. For non-numeric values, the method returns false.


console.log( isnan( NaN ) );
// returns true

console.log( isnan( '5' ) );
// returns false

console.log( isnan( 5 ) );
// returns false

To run the example code from the top-level application directory,

$ node ./examples/index.js



Unit tests use the Mocha test framework with Chai assertions. To run the tests, execute the following command in the top-level application directory:

$ make test

All new feature development should have corresponding unit tests to validate correct functionality.

Test Coverage

This repository uses Istanbul as its code coverage tool. To generate a test coverage report, execute the following command in the top-level application directory:

$ make test-cov

Istanbul creates a ./reports/coverage directory. To access an HTML version of the report,

$ make view-cov


MIT license.


Copyright © 2014. Athan Reines.

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