Enum aws_sdk_elasticache::model::SourceType

#[non_exhaustive]
pub enum SourceType {
    CacheCluster,
    CacheParameterGroup,
    CacheSecurityGroup,
    CacheSubnetGroup,
    ReplicationGroup,
    User,
    UserGroup,
    Unknown(UnknownVariantValue),
}

When writing a match expression against SourceType, 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 sourcetype = unimplemented!();
match sourcetype {
    SourceType::CacheCluster => { /* ... */ },
    SourceType::CacheParameterGroup => { /* ... */ },
    SourceType::CacheSecurityGroup => { /* ... */ },
    SourceType::CacheSubnetGroup => { /* ... */ },
    SourceType::ReplicationGroup => { /* ... */ },
    SourceType::User => { /* ... */ },
    SourceType::UserGroup => { /* ... */ },
    other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
    _ => { /* ... */ },
}

The above code demonstrates that when sourcetype represents NewFeature, the execution path will lead to the second last match arm, even though the enum does not contain a variant SourceType::NewFeature in the current version of SDK. The reason is that the variable other, created by the @ operator, is bound to SourceType::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 SourceType::NewFeature is defined. Specifically, when sourcetype represents NewFeature, the execution path will hit the second last match arm as before by virtue of calling as_str on SourceType::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)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

CacheCluster

CacheParameterGroup

CacheSecurityGroup

CacheSubnetGroup

ReplicationGroup

User

UserGroup

Unknown(UnknownVariantValue)

Unknown contains new variants that have been added since this code was generated.

Implementations

impl SourceType

pub fn as_str(&self) -> &str

Returns the &str value of the enum member.

Examples found in repository

src/model.rs (line 11646)

    fn as_ref(&self) -> &str {
        self.as_str()
    }

src/operation_ser.rs (line 1442)

pub fn serialize_operation_crate_operation_describe_events(
    input: &crate::input::DescribeEventsInput,
) -> Result<aws_smithy_http::body::SdkBody, aws_smithy_http::operation::error::SerializationError> {
    let mut out = String::new();
    #[allow(unused_mut)]
    let mut writer = aws_smithy_query::QueryWriter::new(&mut out, "DescribeEvents", "2015-02-02");
    #[allow(unused_mut)]
    let mut scope_417 = writer.prefix("SourceIdentifier");
    if let Some(var_418) = &input.source_identifier {
        scope_417.string(var_418);
    }
    #[allow(unused_mut)]
    let mut scope_419 = writer.prefix("SourceType");
    if let Some(var_420) = &input.source_type {
        scope_419.string(var_420.as_str());
    }
    #[allow(unused_mut)]
    let mut scope_421 = writer.prefix("StartTime");
    if let Some(var_422) = &input.start_time {
        scope_421.date_time(var_422, aws_smithy_types::date_time::Format::DateTime)?;
    }
    #[allow(unused_mut)]
    let mut scope_423 = writer.prefix("EndTime");
    if let Some(var_424) = &input.end_time {
        scope_423.date_time(var_424, aws_smithy_types::date_time::Format::DateTime)?;
    }
    #[allow(unused_mut)]
    let mut scope_425 = writer.prefix("Duration");
    if let Some(var_426) = &input.duration {
        scope_425.number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_426).into()),
        );
    }
    #[allow(unused_mut)]
    let mut scope_427 = writer.prefix("MaxRecords");
    if let Some(var_428) = &input.max_records {
        scope_427.number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_428).into()),
        );
    }
    #[allow(unused_mut)]
    let mut scope_429 = writer.prefix("Marker");
    if let Some(var_430) = &input.marker {
        scope_429.string(var_430);
    }
    writer.finish();
    Ok(aws_smithy_http::body::SdkBody::from(out))
}

pub const fn values() -> &'static [&'static str]

Returns all the &str values of the enum members.

Trait Implementations

impl AsRef<str> for SourceType

fn as_ref(&self) -> &str

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for SourceType

fn clone(&self) -> SourceType

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SourceType

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<&str> for SourceType

fn from(s: &str) -> Self

Converts to this type from the input type.

impl FromStr for SourceType

type Err = Infallible

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl Hash for SourceType

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where
    H: Hasher,
    Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for SourceType

fn cmp(&self, other: &SourceType) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere
    Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl PartialEq<SourceType> for SourceType

fn eq(&self, other: &SourceType) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd<SourceType> for SourceType

fn partial_cmp(&self, other: &SourceType) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for SourceType

impl StructuralEq for SourceType

impl StructuralPartialEq for SourceType