=== LOL Lift ===

LOL has a special function `lift` that has the type of its argument:

  lift(0)       has type `0`

The `lift` function is commonly used inside quantifiers:

  all i : I { lift(i == i) }                  has type `un(1)`

Without the `lift` function, one can prove the type instead:

  all i : I { i == i }                        has type `un(I)`

Notice that the path index operator `~` does not need `lift`:

  all i : I { any p : (I ~= I) { p ~ i } }    has type `un(nu(1))`
