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