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