#[non_exhaustive]pub enum CustomizableMetricThreshold {
P90,
P95,
P995,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against CustomizableMetricThreshold
, 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 customizablemetricthreshold = unimplemented!();
match customizablemetricthreshold {
CustomizableMetricThreshold::P90 => { /* ... */ },
CustomizableMetricThreshold::P95 => { /* ... */ },
CustomizableMetricThreshold::P995 => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when customizablemetricthreshold
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant CustomizableMetricThreshold::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
CustomizableMetricThreshold::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 CustomizableMetricThreshold::NewFeature
is defined.
Specifically, when customizablemetricthreshold
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on CustomizableMetricThreshold::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
P90
P95
P995
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 CustomizableMetricThreshold
impl CustomizableMetricThreshold
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 CustomizableMetricThreshold
impl AsRef<str> for CustomizableMetricThreshold
source§impl Clone for CustomizableMetricThreshold
impl Clone for CustomizableMetricThreshold
source§fn clone(&self) -> CustomizableMetricThreshold
fn clone(&self) -> CustomizableMetricThreshold
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for CustomizableMetricThreshold
impl Debug for CustomizableMetricThreshold
source§impl From<&str> for CustomizableMetricThreshold
impl From<&str> for CustomizableMetricThreshold
source§impl Hash for CustomizableMetricThreshold
impl Hash for CustomizableMetricThreshold
source§impl Ord for CustomizableMetricThreshold
impl Ord for CustomizableMetricThreshold
source§fn cmp(&self, other: &CustomizableMetricThreshold) -> Ordering
fn cmp(&self, other: &CustomizableMetricThreshold) -> 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 CustomizableMetricThreshold
impl PartialEq for CustomizableMetricThreshold
source§fn eq(&self, other: &CustomizableMetricThreshold) -> bool
fn eq(&self, other: &CustomizableMetricThreshold) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for CustomizableMetricThreshold
impl PartialOrd for CustomizableMetricThreshold
source§fn partial_cmp(&self, other: &CustomizableMetricThreshold) -> Option<Ordering>
fn partial_cmp(&self, other: &CustomizableMetricThreshold) -> 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 CustomizableMetricThreshold
impl StructuralEq for CustomizableMetricThreshold
impl StructuralPartialEq for CustomizableMetricThreshold
Auto Trait Implementations§
impl RefUnwindSafe for CustomizableMetricThreshold
impl Send for CustomizableMetricThreshold
impl Sync for CustomizableMetricThreshold
impl Unpin for CustomizableMetricThreshold
impl UnwindSafe for CustomizableMetricThreshold
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
§impl<Q, K> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.