## Class

class Foo
  attr_accessor :bar
end

a = Foo.new
b = a

a.bar = "hello"
b.bar = "bye"

puts "a == b #{a == b}"
puts "a === b #{a === b}"
puts "a.equal?(b) #{a.equal?(b)}"

## Output

a == b true
a === b true
a.equal?(b) true