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