Question

I’m looking at the documentation for Ruby. I’m confused between using %w() or %W() (Later W is upcase). What is the difference between both? Can you point me to some documentation?

Answer 1

When capitalized, the array is constructed from strings that are interpolated, as would happen in a double-quoted string; when lowercased, it is constructed from strings that are not interpolated, as would happen in a single-quoted string. For example:

irb(main):001:0> foo = "bar"
=> "bar"
irb(main):002:0> %w(#{foo} bar baz)
=> ["\#{foo}", "bar", "baz"]
irb(main):003:0> %W(#{foo} bar baz)
=> ["bar", "bar", "baz"]
irb(main):004:0> ^D