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So, I’d like to submit Object#blank? as an RCR. I use this code in nearly all of my web application projects.

 class Object
   def blank?
     if respond_to? :empty?
       empty?
     elsif respond_to? :zero?
       zero?
     else
       !self
     end
   end
 end

This has been begging for addition into Ruby for years. A bit of background:

• 2000: Jim Menard suggests nil.empty?.
• 2002: Dave Thomas starts to further work up nil.empty?. Opposition brews. (Note that the possibility of nil becoming an Enumerable is kicked around!)
• 2004: Zero is true … whoda thunk? thread delves in and out of the character of nil, 0, "" and so on. However, the discussion really revolves around whether zero could be treated as false in a future Ruby incarnation.
• 2005: Just last month, Dan Fitzpatrick revisited the same nil.empty? pitch we’ve seen in years past.

In all, the two major points of backlash have been:

1. Naming the thing. Some feel that empty? implies a container. A container which isn’t there for nil and 0. Another suggestion was vapid? but, uh, no.
2. That there is no case in which 0 should be grouped with nil and "". I suppose many people are more commonly looking for "0" to belong to this group as well. Which means you have to use .to_i.zero?. Very similar to .to_s.empty?.

I’m thinking Object#blank? is a good solution. The name doesn’t imply a container. It implies valuelessness, which is what we are testing for.

This reduces the common case of:

 if venue['neighborhood'].to_s.empty?

To:

 if venue['neighborhood'].blank?

I’ve grouped 0 in there as well. It’s useful for YAML. Since YAML loads types naturally, you rarely run into a string like "0". And since I’m calling zero?, it works for floats as well.

Given this YAML invoice:

 sku:   BSK115
 price: 15.60
 tax:   0.00
 total: 15.60

I can easily check the tax, covering the case in which the tax is completely left out.

 print "Tax-free" if invoice['tax'].blank?

So, what do you think? Worthwhile RCR? Am I off on the name? Has our time come for this at last?