Function _expect_deserialize_key 

pub(crate) fn _expect_deserialize_key<'a, K>(key: Result<Key<'a>>) -> Key<'a, K>
where
    K: Deserialize<'a>,

Deserializes a key and treats any input or codec error as fatal.

The returned key may borrow from the original raw bytes. Prefer the fallible helper when a caller can propagate decoding failure.

Panics

Panics if the input is an error or the key cannot be deserialized.