Is There a Better Way of Checking Nil or Length == 0 of a String in Ruby?

Question

Is there a better way than the following to check to see if a string is nil OR has a length of 0 in Ruby?

if !my_str         


        

Answer 1

nil? can be omitted in boolean contexts. Generally, you can use this to replicate the C# code:

return my_string.nil? || my_string.empty?

Answer 2

When I'm not worried about performance, I'll often use this:

if my_string.to_s == ''
  # It's nil or empty
end

There are various variations, of course...

if my_string.to_s.strip.length == 0
  # It's nil, empty, or just whitespace
end

Answer 3

If you are willing to require ActiveSupport you can just use the #blank? method, which is defined for both NilClass and String.

Answer 4

Check for Empty Strings in Plain Ruby While Avoiding NameError Exceptions

There are some good answers here, but you don't need ActiveSupport or monkey-patching to address the common use case here. For example:

my_string.to_s.empty? if defined? my_string

This will "do the right thing" if my_string is nil or an empty string, but will not raise a NameError exception if my_string is not defined. This is generally preferable to the more contrived:

my_string.to_s.empty? rescue NameError

or its more verbose ilk, because exceptions should really be saved for things you don't expect to happen. In this case, while it might be a common error, an undefined variable isn't really an exceptional circumstance, so it should be handled accordingly.

Your mileage may vary.