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