Enum aws_sdk_glue::types::MetadataOperation
source · #[non_exhaustive]pub enum MetadataOperation {
Create,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against MetadataOperation, 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 metadataoperation = unimplemented!();
match metadataoperation {
MetadataOperation::Create => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when metadataoperation represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant MetadataOperation::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
MetadataOperation::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 MetadataOperation::NewFeature is defined.
Specifically, when metadataoperation represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on MetadataOperation::NewFeature also yielding "NewFeature".
Explicitly matching on the Unknown variant should
be avoided for two reasons:
- The inner data
UnknownVariantValueis 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
Create
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 MetadataOperation
impl MetadataOperation
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 MetadataOperation
impl AsRef<str> for MetadataOperation
source§impl Clone for MetadataOperation
impl Clone for MetadataOperation
source§fn clone(&self) -> MetadataOperation
fn clone(&self) -> MetadataOperation
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moresource§impl Debug for MetadataOperation
impl Debug for MetadataOperation
source§impl From<&str> for MetadataOperation
impl From<&str> for MetadataOperation
source§impl FromStr for MetadataOperation
impl FromStr for MetadataOperation
source§impl Hash for MetadataOperation
impl Hash for MetadataOperation
source§impl Ord for MetadataOperation
impl Ord for MetadataOperation
source§fn cmp(&self, other: &MetadataOperation) -> Ordering
fn cmp(&self, other: &MetadataOperation) -> 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 MetadataOperation
impl PartialEq for MetadataOperation
source§fn eq(&self, other: &MetadataOperation) -> bool
fn eq(&self, other: &MetadataOperation) -> bool
self and other values to be equal, and is used
by ==.source§impl PartialOrd for MetadataOperation
impl PartialOrd for MetadataOperation
source§fn partial_cmp(&self, other: &MetadataOperation) -> Option<Ordering>
fn partial_cmp(&self, other: &MetadataOperation) -> 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 MetadataOperation
impl StructuralEq for MetadataOperation
impl StructuralPartialEq for MetadataOperation
Auto Trait Implementations§
impl RefUnwindSafe for MetadataOperation
impl Send for MetadataOperation
impl Sync for MetadataOperation
impl Unpin for MetadataOperation
impl UnwindSafe for MetadataOperation
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
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key and return true if they are equal.