Would be cool if this was possible. I know(ish) why it's hard to do.... But it would be cool :-)

meh.rb

def ok a ; puts "ok #{a} " ; end
ok 1                                    # => "ok 1"
def yo a ; puts "yo #{a}" ; end
yo 1                                    # => "yo 1"
ok(a), yo(b) = [1,2]                    # => exception!
a , b = [1,2]; ok(a) ; yo(b)             # => meh!

Interesting but how often would you use it?

hm, for example in Sinatra:

get '/lolz' do

  # something
  body(b), status(x) = return_body_and_status(some_data)

end

or some cool processing stuff like

[ a.reverse, b.downcase = ["ab", "AA"] ].reduce("") { |c,i| c + i } # => "baaa"

As long as it would be quite a nice feature, I think it would also mess with the code readability. At least from my pythonic point of view :). BTW, it doesn't work in Python, too.