is-blank-js

A JavaScript utility to check for blank values, inspired by Ruby on Rails' blank? method.

This library extends the prototypes of String, Array, Object, and Boolean to include an isBlank() method.

Installation

npm install is-blank-js

Usage

First, require the package to extend the prototypes:

require('is-blank-js');

Then, you can use the isBlank() method on your objects:

Strings

A string is blank if it's empty or contains only whitespace.

"".isBlank() // => true
"   ".isBlank() // => true
"hello".isBlank() // => false

Arrays

An array is blank if it's empty.

[].isBlank() // => true
[1, 2].isBlank() // => false

Objects

An object is blank if it's a plain object with no keys.

({}).isBlank() // => true
({ a: 1 }).isBlank() // => false

Booleans

A boolean is blank if it's false.

false.isBlank() // => true
true.isBlank() // => false

Numbers

A number is never blank.

(0).isBlank() // => false
(1).isBlank() // => false

Comparison to Rails' blank?

This library aims to replicate the behavior of Rails' blank? method for common JavaScript types.

| Value in JavaScript | isBlank() | | ------------------- | ----------- | | "" | true | | " " | true | | [] | true | | {} | true | | false | true | | true | false | | 0 | false | | null | (error) | | undefined | (error) |

Note: This library does not handle null or undefined because they don't have prototypes to extend. Calling isBlank() on null or undefined will result in a TypeError.

Development

To run the tests:

node test.js