Let's say I have an array, each element of which is a 2-dimensional array 
of ints.

I want to sort with the first element in the 2D array taking precedence, 
but using the second as a tiebreaker.

So far, I haven't come up with a nice idiom that doesn't seem a bit kludgy:
What I tried was to do something like:
x.sort {|a,b| a[0]<=>b[0] || a[1]<=>b[1]}
but 0 is not false in Ruby so this doesn't work.

x.sort {|a,b| 2*(a[0]<=>b[0]) + (a[1]<=>b[1])}
works, but is non-intuitive and not pretty.

Does anyone have a nice clean rubyesque idiom for this?