Today I Learned

A Hashrocket project

Numbers Are Empty

The lodash project comes with a ton of handy JavaScript utilities including the _.isEmpty() function. This is great for checking if Arrays, Objects, and Strings are empty. The following is how this function is defined in the docs:

Checks if value is an empty collection or object. A value is considered empty if it’s an arguments object, array, string, or jQuery-like collection with a length of 0 or has no own enumerable properties.

Having not examined this definition too closely and because I primarily write Rails code from day to day, I conflated _.isEmpty() with the #blank? method provided by Rails’ ActiveSupport. This holds true for the most part, but quickly defies expectations when it comes to numbers.

> _.isEmpty(1)
// true