#[non_exhaustive]pub enum ValidateStateMachineDefinitionResultCode {
Fail,
Ok,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against ValidateStateMachineDefinitionResultCode, 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 validatestatemachinedefinitionresultcode = unimplemented!();
match validatestatemachinedefinitionresultcode {
ValidateStateMachineDefinitionResultCode::Fail => { /* ... */ },
ValidateStateMachineDefinitionResultCode::Ok => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when validatestatemachinedefinitionresultcode represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant ValidateStateMachineDefinitionResultCode::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
ValidateStateMachineDefinitionResultCode::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 ValidateStateMachineDefinitionResultCode::NewFeature is defined.
Specifically, when validatestatemachinedefinitionresultcode represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on ValidateStateMachineDefinitionResultCode::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
Fail
Ok
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 ValidateStateMachineDefinitionResultCode
impl ValidateStateMachineDefinitionResultCode
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 Clone for ValidateStateMachineDefinitionResultCode
impl Clone for ValidateStateMachineDefinitionResultCode
source§fn clone(&self) -> ValidateStateMachineDefinitionResultCode
fn clone(&self) -> ValidateStateMachineDefinitionResultCode
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moresource§impl Ord for ValidateStateMachineDefinitionResultCode
impl Ord for ValidateStateMachineDefinitionResultCode
source§fn cmp(&self, other: &ValidateStateMachineDefinitionResultCode) -> Ordering
fn cmp(&self, other: &ValidateStateMachineDefinitionResultCode) -> 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 ValidateStateMachineDefinitionResultCode
impl PartialEq for ValidateStateMachineDefinitionResultCode
source§fn eq(&self, other: &ValidateStateMachineDefinitionResultCode) -> bool
fn eq(&self, other: &ValidateStateMachineDefinitionResultCode) -> bool
self and other values to be equal, and is used
by ==.source§impl PartialOrd for ValidateStateMachineDefinitionResultCode
impl PartialOrd for ValidateStateMachineDefinitionResultCode
source§fn partial_cmp(
&self,
other: &ValidateStateMachineDefinitionResultCode
) -> Option<Ordering>
fn partial_cmp( &self, other: &ValidateStateMachineDefinitionResultCode ) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self and other) and is used by the <=
operator. Read moreimpl Eq for ValidateStateMachineDefinitionResultCode
impl StructuralPartialEq for ValidateStateMachineDefinitionResultCode
Auto Trait Implementations§
impl Freeze for ValidateStateMachineDefinitionResultCode
impl RefUnwindSafe for ValidateStateMachineDefinitionResultCode
impl Send for ValidateStateMachineDefinitionResultCode
impl Sync for ValidateStateMachineDefinitionResultCode
impl Unpin for ValidateStateMachineDefinitionResultCode
impl UnwindSafe for ValidateStateMachineDefinitionResultCode
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<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