Make Uint128 inner value private

[webmaster128]

[ethanfrey]

This will break a lot of code.

In particular, if I want to use Uint128 in a match, I cannot do:

match amount {
  Uint128::zero() => do_something(),
  _ => do_something_else(),
}

As you cannot use functions in the branches of match. Maybe this works with const fn? In any case, if you deprecate Uint128(0), please ensure there is a replacement for the above idiom (which I used twice today)

[webmaster128]

We have a getter method to get the inner value: a.u128() which can be used everywhere when you need the primary type. Then the code above becomes:

match amount.u128() {
  0 => do_something(),
  1..=234 => do_something_else(),
  _ => do_something_else_else(),
}

[ethanfrey]

Hmmm... I guess this works.