error[E0308]: mismatched types
   --> src/factoid.rs:105:18
    |
105 |             bs = bs.skip_while(|x| x == &b)
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^ expected struct `std::iter::Peekable`, found struct `std::iter::SkipWhile`
    |
    = note: expected type `std::iter::Peekable<_>`
               found type `std::iter::SkipWhile<std::iter::Peekable<_>, [closure@src/factoid.rs:105:32: 105:43 b:_]>`