Operations with Ranges

range_operations.rb

class Range
  def end_at(x)
    Range.new(self.begin, x)
  end
  
  def start_at(x)
    Range.new(x, self.end)
  end
end

# Initial Range
range = 1..10

# New end
p range.end_at(100)
# => 1..100

# New start
p range.start_at(5)
# => 1..5