Enum aws_sdk_wafv2::types::LabelMatchScope
source · #[non_exhaustive]pub enum LabelMatchScope {
Label,
Namespace,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against LabelMatchScope
, 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 labelmatchscope = unimplemented!();
match labelmatchscope {
LabelMatchScope::Label => { /* ... */ },
LabelMatchScope::Namespace => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when labelmatchscope
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant LabelMatchScope::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
LabelMatchScope::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 LabelMatchScope::NewFeature
is defined.
Specifically, when labelmatchscope
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on LabelMatchScope::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
Label
Namespace
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 LabelMatchScope
impl LabelMatchScope
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 LabelMatchScope
impl AsRef<str> for LabelMatchScope
source§impl Clone for LabelMatchScope
impl Clone for LabelMatchScope
source§fn clone(&self) -> LabelMatchScope
fn clone(&self) -> LabelMatchScope
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for LabelMatchScope
impl Debug for LabelMatchScope
source§impl Display for LabelMatchScope
impl Display for LabelMatchScope
source§impl From<&str> for LabelMatchScope
impl From<&str> for LabelMatchScope
source§impl FromStr for LabelMatchScope
impl FromStr for LabelMatchScope
source§impl Hash for LabelMatchScope
impl Hash for LabelMatchScope
source§impl Ord for LabelMatchScope
impl Ord for LabelMatchScope
source§fn cmp(&self, other: &LabelMatchScope) -> Ordering
fn cmp(&self, other: &LabelMatchScope) -> 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 LabelMatchScope
impl PartialEq for LabelMatchScope
source§fn eq(&self, other: &LabelMatchScope) -> bool
fn eq(&self, other: &LabelMatchScope) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for LabelMatchScope
impl PartialOrd for LabelMatchScope
source§fn partial_cmp(&self, other: &LabelMatchScope) -> Option<Ordering>
fn partial_cmp(&self, other: &LabelMatchScope) -> 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 LabelMatchScope
impl StructuralPartialEq for LabelMatchScope
Auto Trait Implementations§
impl Freeze for LabelMatchScope
impl RefUnwindSafe for LabelMatchScope
impl Send for LabelMatchScope
impl Sync for LabelMatchScope
impl Unpin for LabelMatchScope
impl UnwindSafe for LabelMatchScope
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