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