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