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