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