#[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
UnknownVariantValueis 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 contains new variants that have been added since this code was generated.
Implementations§
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
source§fn partial_cmp(&self, other: &NumericEqualityMatchOperator) -> Option<Ordering>
fn partial_cmp(&self, other: &NumericEqualityMatchOperator) -> 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 NumericEqualityMatchOperator
impl StructuralEq for NumericEqualityMatchOperator
impl StructuralPartialEq for NumericEqualityMatchOperator
Auto Trait Implementations§
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
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key and return true if they are equal.