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