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