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