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