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