https://gist.github.com/hanachin/2983960d3ef180b6c929e3ac9730c9bb

hanachin_answer.rb

# Q1

"Hello world".then do
  # case x = 1.010101
  case x = 1..010101
  in ^x
    puts "Goodbye world"
  end
rescue NoMatchingPatternError
  puts @1
end

# Q2

def say
  Proc.new
end

# greeting = say {
greeting = say &{
  case "Hello world"
  in x => y if x = 1
  then
    1
  else
    0
  end & 1 => y
}

puts greeting.call(1)

# Q3

# ?...?.?%??.:puts.:[]==="Hello world":%??
?...?.?%??.:puts.:[] ==="Hello world":%??