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