prefer static_map! over explicit unsafe in serde deserialisation #17
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Instead of going over all the entries and checking if they are initialised and then going over them again and unwrapping unsafely, we can just go over it once and report the error on first failure. The semantics should be exactly the same but we no longer have an explicit `unsafe` in here: it's moved behind the `static_map!` macro instead which can be considered more battle-hardened. If we're accepting unsafe then it might make more sense to do something like `[MaybeUninit<T>; L::LENGTH]` though something like the `Builder` is needed to make this ergonomic. Either way, I think the version in this commit at least hides the magic. PS: I checked if we can just replace `.unwrap_unchecked()` with `.unwrap()` but it seems that rustc is not able to notice that it will never fail so it generates panic code anyway.
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Instead of going over all the entries and checking if they are initialised and then going over them
again and unwrapping unsafely, we can just go over it once and report the error on first failure. The semantics should be exactly the same but we no
longer have an explicit
unsafein here: it'smoved behind the
static_map!macro instead which can be considered more battle-hardened.If we're accepting unsafe then it might make more
sense to do something like
[MaybeUninit<T>; L::LENGTH]though something like theBuilderis needed to make this ergonomic. Either way, I think the version in this commit at least hides themagic.
PS: I checked if we can just replace
.unwrap_unchecked()with.unwrap()but itseems that rustc is not able to notice that it
will never fail so it generates panic code anyway.