Enum aws_sdk_ec2::types::HostTenancy
source · #[non_exhaustive]pub enum HostTenancy {
Dedicated,
Host,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against HostTenancy
, 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 hosttenancy = unimplemented!();
match hosttenancy {
HostTenancy::Dedicated => { /* ... */ },
HostTenancy::Host => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when hosttenancy
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant HostTenancy::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
HostTenancy::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 HostTenancy::NewFeature
is defined.
Specifically, when hosttenancy
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on HostTenancy::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
Dedicated
Host
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for HostTenancy
impl AsRef<str> for HostTenancy
source§impl Clone for HostTenancy
impl Clone for HostTenancy
source§fn clone(&self) -> HostTenancy
fn clone(&self) -> HostTenancy
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for HostTenancy
impl Debug for HostTenancy
source§impl From<&str> for HostTenancy
impl From<&str> for HostTenancy
source§impl FromStr for HostTenancy
impl FromStr for HostTenancy
source§impl Hash for HostTenancy
impl Hash for HostTenancy
source§impl Ord for HostTenancy
impl Ord for HostTenancy
source§fn cmp(&self, other: &HostTenancy) -> Ordering
fn cmp(&self, other: &HostTenancy) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq<HostTenancy> for HostTenancy
impl PartialEq<HostTenancy> for HostTenancy
source§fn eq(&self, other: &HostTenancy) -> bool
fn eq(&self, other: &HostTenancy) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<HostTenancy> for HostTenancy
impl PartialOrd<HostTenancy> for HostTenancy
source§fn partial_cmp(&self, other: &HostTenancy) -> Option<Ordering>
fn partial_cmp(&self, other: &HostTenancy) -> 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 HostTenancy
impl StructuralEq for HostTenancy
impl StructuralPartialEq for HostTenancy
Auto Trait Implementations§
impl RefUnwindSafe for HostTenancy
impl Send for HostTenancy
impl Sync for HostTenancy
impl Unpin for HostTenancy
impl UnwindSafe for HostTenancy
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.