documentcloud/underscore — pull request #677 by derekprior (2012-07-17 21:50:02+00:00)
Title: Add isNullOrUndefined

Perhaps I'm "doing it wrong" but I often want to check to see if
something is (or more-often, is NOT) null or undefined. I know it's a
simple method to write and include yourself, but from my novice
perspective it seems like a useful inclusion in base.

I checked to see if this has been discussed before on the tracker and didn't find anything.