Add Numbers Are Empty as a javascript til

README.md

@@ -7,7 +7,7 @@ variety of languages and technologies. These are things that don't really
 warrant a full blog post. These are mostly things I learn by pairing with
 smart people at [Hashrocket](http://hashrocket.com/).
 
-_373 TILs and counting..._
+_374 TILs and counting..._
 
 ---
 
@@ -130,6 +130,7 @@ _373 TILs and counting..._
 - [Create An Array Containing 1 To N](javascript/create-an-array-containing-1-to-n.md)
 - [Enable ES7 Transforms With react-rails](javascript/enable-es7-transforms-with-react-rails.md)
 - [Immutable Remove With The Spread Operator](javascript/immutable-remove-with-the-spread-operator.md)
+- [Numbers Are Empty](javascript/numbers-are-empty.md)
 - [Object Initialization With Shorthand Property Names](javascript/object-initialization-with-shorthand-property-names.md)
 - [Random Cannot Be Seeded](javascript/random-cannot-be-seeded.md)
 - [Splat Arguments To A Function](javascript/splat-arguments-to-a-function.md)

javascript/numbers-are-empty.md

@@ -0,0 +1,21 @@
+# Numbers Are Empty
+
+The [`lodash`](https://lodash.com/) project comes with a ton of handy
+JavaScript utilities including the
+[`_.isEmpty()`](https://lodash.com/docs#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.
+
+```javascript
+> _.isEmpty(1)
+// true
+```