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