#[non_exhaustive]
pub enum DataDistributionType {
Fullyreplicated,
Shardedbys3Key,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against DataDistributionType
, 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 datadistributiontype = unimplemented!();
match datadistributiontype {
DataDistributionType::Fullyreplicated => { /* ... */ },
DataDistributionType::Shardedbys3Key => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when datadistributiontype
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant DataDistributionType::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
DataDistributionType::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 DataDistributionType::NewFeature
is defined.
Specifically, when datadistributiontype
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on DataDistributionType::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
Fullyreplicated
Shardedbys3Key
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for DataDistributionType
impl AsRef<str> for DataDistributionType
source§impl Clone for DataDistributionType
impl Clone for DataDistributionType
source§fn clone(&self) -> DataDistributionType
fn clone(&self) -> DataDistributionType
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for DataDistributionType
impl Debug for DataDistributionType
source§impl From<&str> for DataDistributionType
impl From<&str> for DataDistributionType
source§impl FromStr for DataDistributionType
impl FromStr for DataDistributionType
source§impl Hash for DataDistributionType
impl Hash for DataDistributionType
source§impl Ord for DataDistributionType
impl Ord for DataDistributionType
source§fn cmp(&self, other: &DataDistributionType) -> Ordering
fn cmp(&self, other: &DataDistributionType) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl PartialEq<DataDistributionType> for DataDistributionType
impl PartialEq<DataDistributionType> for DataDistributionType
source§fn eq(&self, other: &DataDistributionType) -> bool
fn eq(&self, other: &DataDistributionType) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<DataDistributionType> for DataDistributionType
impl PartialOrd<DataDistributionType> for DataDistributionType
source§fn partial_cmp(&self, other: &DataDistributionType) -> Option<Ordering>
fn partial_cmp(&self, other: &DataDistributionType) -> 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 DataDistributionType
impl StructuralEq for DataDistributionType
impl StructuralPartialEq for DataDistributionType
Auto Trait Implementations§
impl RefUnwindSafe for DataDistributionType
impl Send for DataDistributionType
impl Sync for DataDistributionType
impl Unpin for DataDistributionType
impl UnwindSafe for DataDistributionType
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.