Enum aws_sdk_ec2::model::Affinity

#[non_exhaustive]
pub enum Affinity {
    Default,
    Host,
    Unknown(UnknownVariantValue),
}

When writing a match expression against Affinity, 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 affinity = unimplemented!();
match affinity {
    Affinity::Default => { /* ... */ },
    Affinity::Host => { /* ... */ },
    other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
    _ => { /* ... */ },
}

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

Default

Host

Unknown(UnknownVariantValue)

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

Implementations

impl Affinity

pub fn as_str(&self) -> &str

Returns the &str value of the enum member.

Examples found in repository

src/model.rs (line 46916)

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

src/operation_ser.rs (line 18088)

pub fn serialize_operation_crate_operation_modify_instance_placement(
    input: &crate::input::ModifyInstancePlacementInput,
) -> 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, "ModifyInstancePlacement", "2016-11-15");
    #[allow(unused_mut)]
    let mut scope_5082 = writer.prefix("Affinity");
    if let Some(var_5083) = &input.affinity {
        scope_5082.string(var_5083.as_str());
    }
    #[allow(unused_mut)]
    let mut scope_5084 = writer.prefix("GroupName");
    if let Some(var_5085) = &input.group_name {
        scope_5084.string(var_5085);
    }
    #[allow(unused_mut)]
    let mut scope_5086 = writer.prefix("HostId");
    if let Some(var_5087) = &input.host_id {
        scope_5086.string(var_5087);
    }
    #[allow(unused_mut)]
    let mut scope_5088 = writer.prefix("InstanceId");
    if let Some(var_5089) = &input.instance_id {
        scope_5088.string(var_5089);
    }
    #[allow(unused_mut)]
    let mut scope_5090 = writer.prefix("Tenancy");
    if let Some(var_5091) = &input.tenancy {
        scope_5090.string(var_5091.as_str());
    }
    #[allow(unused_mut)]
    let mut scope_5092 = writer.prefix("PartitionNumber");
    if let Some(var_5093) = &input.partition_number {
        scope_5092.number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_5093).into()),
        );
    }
    #[allow(unused_mut)]
    let mut scope_5094 = writer.prefix("HostResourceGroupArn");
    if let Some(var_5095) = &input.host_resource_group_arn {
        scope_5094.string(var_5095);
    }
    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 Affinity

fn as_ref(&self) -> &str

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

impl Clone for Affinity

fn clone(&self) -> Affinity

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Affinity

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

Formats the value using the given formatter.

impl From<&str> for Affinity

fn from(s: &str) -> Self

Converts to this type from the input type.

impl FromStr for Affinity

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 Affinity

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 Affinity

fn cmp(&self, other: &Affinity) -> 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<Affinity> for Affinity

fn eq(&self, other: &Affinity) -> 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<Affinity> for Affinity

fn partial_cmp(&self, other: &Affinity) -> 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 Affinity

impl StructuralEq for Affinity

impl StructuralPartialEq for Affinity