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