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