#[non_exhaustive]pub enum StorageAccessLevel {
Private,
Protected,
Public,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against StorageAccessLevel, 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 storageaccesslevel = unimplemented!();
match storageaccesslevel {
StorageAccessLevel::Private => { /* ... */ },
StorageAccessLevel::Protected => { /* ... */ },
StorageAccessLevel::Public => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when storageaccesslevel represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant StorageAccessLevel::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
StorageAccessLevel::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 StorageAccessLevel::NewFeature is defined.
Specifically, when storageaccesslevel represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on StorageAccessLevel::NewFeature also yielding "NewFeature".
Explicitly matching on the Unknown variant should
be avoided for two reasons:
- The inner data
UnknownVariantValueis 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
Private
Protected
Public
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 StorageAccessLevel
impl StorageAccessLevel
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 StorageAccessLevel
impl AsRef<str> for StorageAccessLevel
source§impl Clone for StorageAccessLevel
impl Clone for StorageAccessLevel
source§fn clone(&self) -> StorageAccessLevel
fn clone(&self) -> StorageAccessLevel
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moresource§impl Debug for StorageAccessLevel
impl Debug for StorageAccessLevel
source§impl Display for StorageAccessLevel
impl Display for StorageAccessLevel
source§impl From<&str> for StorageAccessLevel
impl From<&str> for StorageAccessLevel
source§impl FromStr for StorageAccessLevel
impl FromStr for StorageAccessLevel
source§impl Hash for StorageAccessLevel
impl Hash for StorageAccessLevel
source§impl Ord for StorageAccessLevel
impl Ord for StorageAccessLevel
source§fn cmp(&self, other: &StorageAccessLevel) -> Ordering
fn cmp(&self, other: &StorageAccessLevel) -> 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 StorageAccessLevel
impl PartialEq for StorageAccessLevel
source§fn eq(&self, other: &StorageAccessLevel) -> bool
fn eq(&self, other: &StorageAccessLevel) -> bool
self and other values to be equal, and is used
by ==.source§impl PartialOrd for StorageAccessLevel
impl PartialOrd for StorageAccessLevel
source§fn partial_cmp(&self, other: &StorageAccessLevel) -> Option<Ordering>
fn partial_cmp(&self, other: &StorageAccessLevel) -> 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 StorageAccessLevel
impl StructuralPartialEq for StorageAccessLevel
Auto Trait Implementations§
impl Freeze for StorageAccessLevel
impl RefUnwindSafe for StorageAccessLevel
impl Send for StorageAccessLevel
impl Sync for StorageAccessLevel
impl Unpin for StorageAccessLevel
impl UnwindSafe for StorageAccessLevel
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.source§impl<T> Instrument for T
impl<T> Instrument for T
source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
source§impl<T> IntoEither for T
impl<T> IntoEither for T
source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left is true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read moresource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left(&self) returns true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read more