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