Enum aws_sdk_ec2::model::LaunchTemplateHttpTokensState

#[non_exhaustive]
pub enum LaunchTemplateHttpTokensState {
    Optional,
    Required,
    Unknown(UnknownVariantValue),
}

When writing a match expression against LaunchTemplateHttpTokensState, 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 launchtemplatehttptokensstate = unimplemented!();
match launchtemplatehttptokensstate {
    LaunchTemplateHttpTokensState::Optional => { /* ... */ },
    LaunchTemplateHttpTokensState::Required => { /* ... */ },
    other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
    _ => { /* ... */ },
}

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

Optional

Required

Unknown(UnknownVariantValue)

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

Implementations

impl LaunchTemplateHttpTokensState

pub fn as_str(&self) -> &str

Returns the &str value of the enum member.

Examples found in repository

src/model.rs (line 60358)

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

src/query_ser.rs (line 4498)

pub fn serialize_structure_crate_model_launch_template_instance_metadata_options_request(
    mut writer: aws_smithy_query::QueryValueWriter,
    input: &crate::model::LaunchTemplateInstanceMetadataOptionsRequest,
) -> Result<(), aws_smithy_http::operation::error::SerializationError> {
    #[allow(unused_mut)]
    let mut scope_1278 = writer.prefix("HttpTokens");
    if let Some(var_1279) = &input.http_tokens {
        scope_1278.string(var_1279.as_str());
    }
    #[allow(unused_mut)]
    let mut scope_1280 = writer.prefix("HttpPutResponseHopLimit");
    if let Some(var_1281) = &input.http_put_response_hop_limit {
        scope_1280.number(
            #[allow(clippy::useless_conversion)]
            aws_smithy_types::Number::NegInt((*var_1281).into()),
        );
    }
    #[allow(unused_mut)]
    let mut scope_1282 = writer.prefix("HttpEndpoint");
    if let Some(var_1283) = &input.http_endpoint {
        scope_1282.string(var_1283.as_str());
    }
    #[allow(unused_mut)]
    let mut scope_1284 = writer.prefix("HttpProtocolIpv6");
    if let Some(var_1285) = &input.http_protocol_ipv6 {
        scope_1284.string(var_1285.as_str());
    }
    #[allow(unused_mut)]
    let mut scope_1286 = writer.prefix("InstanceMetadataTags");
    if let Some(var_1287) = &input.instance_metadata_tags {
        scope_1286.string(var_1287.as_str());
    }
    Ok(())
}

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

Returns all the &str values of the enum members.

Trait Implementations

impl AsRef<str> for LaunchTemplateHttpTokensState

fn as_ref(&self) -> &str

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

impl Clone for LaunchTemplateHttpTokensState

fn clone(&self) -> LaunchTemplateHttpTokensState

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for LaunchTemplateHttpTokensState

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

Formats the value using the given formatter.

impl From<&str> for LaunchTemplateHttpTokensState

fn from(s: &str) -> Self

Converts to this type from the input type.

impl FromStr for LaunchTemplateHttpTokensState

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 LaunchTemplateHttpTokensState

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 LaunchTemplateHttpTokensState

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

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

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

impl StructuralEq for LaunchTemplateHttpTokensState

impl StructuralPartialEq for LaunchTemplateHttpTokensState