'with' keyword for Ruby, if that's your thing

with.rb

module Kernel
  def with(obj, &block)
    obj.instance_eval(&block)
  end
end

with 'Hi' do
  length # => 2
  upcase # => "HI"
  downcase # => "hi"
  foo = length
  foo + 2 # => 4
  Math.sin(1) # => 0.841470984807897
end