Enum aws_sdk_ec2::types::TokenState
source · #[non_exhaustive]pub enum TokenState {
Expired,
Valid,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against TokenState, 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 tokenstate = unimplemented!();
match tokenstate {
TokenState::Expired => { /* ... */ },
TokenState::Valid => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when tokenstate represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant TokenState::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
TokenState::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 TokenState::NewFeature is defined.
Specifically, when tokenstate represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on TokenState::NewFeature also yielding "NewFeature".
Explicitly matching on the Unknown variant should
be avoided for two reasons:
- The inner data
UnknownVariantValueis 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
Expired
Valid
Unknown(UnknownVariantValue)
Unknown. See the docs on this enum for the correct way to handle unknown variants.Unknown contains new variants that have been added since this code was generated.
Implementations§
source§impl TokenState
impl TokenState
source§impl TokenState
impl TokenState
sourcepub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
pub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
Parses the enum value while disallowing unknown variants.
Unknown variants will result in an error.
Trait Implementations§
source§impl AsRef<str> for TokenState
impl AsRef<str> for TokenState
source§impl Clone for TokenState
impl Clone for TokenState
source§fn clone(&self) -> TokenState
fn clone(&self) -> TokenState
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moresource§impl Debug for TokenState
impl Debug for TokenState
source§impl Display for TokenState
impl Display for TokenState
source§impl From<&str> for TokenState
impl From<&str> for TokenState
source§impl FromStr for TokenState
impl FromStr for TokenState
source§impl Hash for TokenState
impl Hash for TokenState
source§impl Ord for TokenState
impl Ord for TokenState
source§fn cmp(&self, other: &TokenState) -> Ordering
fn cmp(&self, other: &TokenState) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl PartialEq for TokenState
impl PartialEq for TokenState
source§impl PartialOrd for TokenState
impl PartialOrd for TokenState
impl Eq for TokenState
impl StructuralPartialEq for TokenState
Auto Trait Implementations§
impl Freeze for TokenState
impl RefUnwindSafe for TokenState
impl Send for TokenState
impl Sync for TokenState
impl Unpin for TokenState
impl UnwindSafe for TokenState
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit)source§impl<Q, K> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key and return true if they are equal.source§impl<T> Instrument for T
impl<T> Instrument for T
source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
source§impl<T> IntoEither for T
impl<T> IntoEither for T
source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left is true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read moresource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
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