#[non_exhaustive]pub enum RetentionPeriod {
Show 17 variants
EighteenMonths,
EightYears,
FiveYears,
FourYears,
NineMonths,
NineYears,
OneYear,
Permanent,
SevenYears,
SixMonths,
SixYears,
TenYears,
ThirtyMonths,
ThreeMonths,
ThreeYears,
TwoYears,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against RetentionPeriod
, 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 retentionperiod = unimplemented!();
match retentionperiod {
RetentionPeriod::EighteenMonths => { /* ... */ },
RetentionPeriod::EightYears => { /* ... */ },
RetentionPeriod::FiveYears => { /* ... */ },
RetentionPeriod::FourYears => { /* ... */ },
RetentionPeriod::NineMonths => { /* ... */ },
RetentionPeriod::NineYears => { /* ... */ },
RetentionPeriod::OneYear => { /* ... */ },
RetentionPeriod::Permanent => { /* ... */ },
RetentionPeriod::SevenYears => { /* ... */ },
RetentionPeriod::SixMonths => { /* ... */ },
RetentionPeriod::SixYears => { /* ... */ },
RetentionPeriod::TenYears => { /* ... */ },
RetentionPeriod::ThirtyMonths => { /* ... */ },
RetentionPeriod::ThreeMonths => { /* ... */ },
RetentionPeriod::ThreeYears => { /* ... */ },
RetentionPeriod::TwoYears => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when retentionperiod
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant RetentionPeriod::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
RetentionPeriod::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 RetentionPeriod::NewFeature
is defined.
Specifically, when retentionperiod
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on RetentionPeriod::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
EighteenMonths
EightYears
FiveYears
FourYears
NineMonths
NineYears
OneYear
Permanent
SevenYears
SixMonths
SixYears
TenYears
ThirtyMonths
ThreeMonths
ThreeYears
TwoYears
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 RetentionPeriod
impl RetentionPeriod
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 RetentionPeriod
impl AsRef<str> for RetentionPeriod
source§impl Clone for RetentionPeriod
impl Clone for RetentionPeriod
source§fn clone(&self) -> RetentionPeriod
fn clone(&self) -> RetentionPeriod
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for RetentionPeriod
impl Debug for RetentionPeriod
source§impl Display for RetentionPeriod
impl Display for RetentionPeriod
source§impl From<&str> for RetentionPeriod
impl From<&str> for RetentionPeriod
source§impl FromStr for RetentionPeriod
impl FromStr for RetentionPeriod
source§impl Hash for RetentionPeriod
impl Hash for RetentionPeriod
source§impl Ord for RetentionPeriod
impl Ord for RetentionPeriod
source§fn cmp(&self, other: &RetentionPeriod) -> Ordering
fn cmp(&self, other: &RetentionPeriod) -> 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 RetentionPeriod
impl PartialEq for RetentionPeriod
source§fn eq(&self, other: &RetentionPeriod) -> bool
fn eq(&self, other: &RetentionPeriod) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for RetentionPeriod
impl PartialOrd for RetentionPeriod
source§fn partial_cmp(&self, other: &RetentionPeriod) -> Option<Ordering>
fn partial_cmp(&self, other: &RetentionPeriod) -> 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 RetentionPeriod
impl StructuralPartialEq for RetentionPeriod
Auto Trait Implementations§
impl Freeze for RetentionPeriod
impl RefUnwindSafe for RetentionPeriod
impl Send for RetentionPeriod
impl Sync for RetentionPeriod
impl Unpin for RetentionPeriod
impl UnwindSafe for RetentionPeriod
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