#[non_exhaustive]pub enum UnauthorizedCode {
CredentialValidationFailed,
Unauthorized,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against UnauthorizedCode
, it is important to ensure
your code is forward-compatible. That is, if a match arm handles a case for a
feature that is supported by the service but has not been represented as an enum
variant in a current version of SDK, your code should continue to work when you
upgrade SDK to a future version in which the enum does include a variant for that
feature.
Here is an example of how you can make a match expression forward-compatible:
# let unauthorizedcode = unimplemented!();
match unauthorizedcode {
UnauthorizedCode::CredentialValidationFailed => { /* ... */ },
UnauthorizedCode::Unauthorized => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when unauthorizedcode
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant UnauthorizedCode::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
UnauthorizedCode::Unknown(UnknownVariantValue("NewFeature".to_owned()))
and calling as_str
on it yields "NewFeature"
.
This match expression is forward-compatible when executed with a newer
version of SDK where the variant UnauthorizedCode::NewFeature
is defined.
Specifically, when unauthorizedcode
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on UnauthorizedCode::NewFeature
also yielding "NewFeature"
.
Explicitly matching on the Unknown
variant should
be avoided for two reasons:
- The inner data
UnknownVariantValue
is opaque, and no further information can be extracted. - It might inadvertently shadow other intended match arms.
Variants (Non-exhaustive)§
This enum is marked as non-exhaustive
CredentialValidationFailed
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
Source§fn clone(&self) -> UnauthorizedCode
fn clone(&self) -> UnauthorizedCode
1.0.0 · Source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moreSource§fn cmp(&self, other: &UnauthorizedCode) -> Ordering
fn cmp(&self, other: &UnauthorizedCode) -> Ordering
1.21.0 · Source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
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impl<Q, K> Equivalent<K> for Q
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fn equivalent(&self, key: &K) -> bool
key
and return true
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Source§fn into_either(self, into_left: bool) -> Either<Self, Self>
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self
into a Left
variant of Either<Self, Self>
if into_left
is true
.
Converts self
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variant of Either<Self, Self>
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fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left(&self)
returns true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read more