Enum aws_sdk_s3::types::QuoteFields
source · #[non_exhaustive]pub enum QuoteFields {
Always,
Asneeded,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against QuoteFields
, 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 quotefields = unimplemented!();
match quotefields {
QuoteFields::Always => { /* ... */ },
QuoteFields::Asneeded => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when quotefields
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant QuoteFields::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
QuoteFields::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 QuoteFields::NewFeature
is defined.
Specifically, when quotefields
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on QuoteFields::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
Always
Asneeded
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 QuoteFields
impl QuoteFields
source§impl QuoteFields
impl QuoteFields
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 QuoteFields
impl AsRef<str> for QuoteFields
source§impl Clone for QuoteFields
impl Clone for QuoteFields
source§fn clone(&self) -> QuoteFields
fn clone(&self) -> QuoteFields
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for QuoteFields
impl Debug for QuoteFields
source§impl Display for QuoteFields
impl Display for QuoteFields
source§impl From<&str> for QuoteFields
impl From<&str> for QuoteFields
source§impl FromStr for QuoteFields
impl FromStr for QuoteFields
source§impl Hash for QuoteFields
impl Hash for QuoteFields
source§impl Ord for QuoteFields
impl Ord for QuoteFields
source§fn cmp(&self, other: &QuoteFields) -> Ordering
fn cmp(&self, other: &QuoteFields) -> 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 QuoteFields
impl PartialEq for QuoteFields
source§impl PartialOrd for QuoteFields
impl PartialOrd for QuoteFields
impl Eq for QuoteFields
impl StructuralPartialEq for QuoteFields
Auto Trait Implementations§
impl Freeze for QuoteFields
impl RefUnwindSafe for QuoteFields
impl Send for QuoteFields
impl Sync for QuoteFields
impl Unpin for QuoteFields
impl UnwindSafe for QuoteFields
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<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)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.