From: Eric Will <rakaur@...>
Date: 2009-04-08T00:10:22+09:00
Subject: barenames and case statements

I've encountered this in the past and thought I was messing something
up, but it's happening still.

Can anyone tell me why this:

puts "ruby-#{RUBY_VERSION} [#{RUBY_PLATFORM}]"

[String, Array, Hash].each do |klass|
    case klass
    when String
        puts "String!"
    when Array
        puts "Array!"
    when Hash
        puts "Hash!"
    else
        puts "I don't know: #{klass}"
    end
end

Produces this:

ruby-1.8.7 [x86_64-linux]
I don't know: String
I don't know: Array
I don't know: Hash

ruby-1.9.1 [x86_64-linux]
I don't know: String
I don't know: Array
I don't know: Hash

Am I missing something here? In order to get the expected result I
have to do this:

[String, Array, Hash].each do |klass|
    case klass.to_s
    when "String"
        puts "String!"
    when "Array"
        puts "Array!"
    when "Hash"
        puts "Hash!"
    else
        puts "I don't know: #{klass}"
    end
end

This works of course, but why doesn't the former? I find it hard to
believe this has been overlooked. What am I missing?

-- Eric Will