I reviewed the changes in P2845R2 (Formatting of std::filesystem::path)
<https://wg21.link/p2845r2> and spotted what I think are a couple of
errors with the lone surrogate examples near the end of section 5,
"Proposal".

First, both examples are actually identical. I think one of them should
have {:?} as the replacement field.

Second, for the escaped example, it is stated that hexadecimal escapes
are produced, but the example output is presented as "\u{d800}"; I think
that should be "\x{d800}".

Tom.