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