Trait CombineAttributeParser 

pub(crate) trait CombineAttributeParser: 'static {
    type Item;

    const PATH: &[Symbol];
    const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind;
    const STABILITY: AttributeStability;
    const ALLOWED_TARGETS: AllowedTargets<'_>;
    const TEMPLATE: AttributeTemplate;
    const SAFETY: AttributeSafety = AttributeSafety::Normal;

    // Required method
    fn extend(
        cx: &mut AcceptContext<'_, '_>,
        args: &ArgParser,
    ) -> impl IntoIterator<Item = Self::Item>;

    // Provided method
    fn finalize_check(_cx: &FinalizeContext<'_, '_>, _attr_span: Span) { ... }
}

Alternative to AttributeParser that automatically handles state management. If multiple attributes appear on an element, combines the values of each into a ThinVec. Combine<T> where T: CombineAttributeParser implements AttributeParser.

CombineAttributeParser can only convert a single kind of attribute, and cannot combine multiple attributes together like is necessary for #[stable()] and #[unstable()] for example.

Required Associated Constants

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

A function that converts individual items (of type Item) into the final attribute.

For example, individual representations from #[repr(...)] attributes into an AttributeKind::Repr(x), where x is a vec of these individual reprs.

const STABILITY: AttributeStability

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

The template this attribute parser should implement. Used for diagnostics.

Provided Associated Constants

const SAFETY: AttributeSafety = AttributeSafety::Normal

Required Associated Types

type Item

Required Methods

fn extend( cx: &mut AcceptContext<'_, '_>, args: &ArgParser, ) -> impl IntoIterator<Item = Self::Item>

Converts a single syntactical attribute to a number of elements of the semantic attribute, or AttributeKind

Provided Methods

fn finalize_check(_cx: &FinalizeContext<'_, '_>, _attr_span: Span)

Optional cross-attribute validation, run once during finalization after all attributes on the item have been parsed. Has access to the sibling attributes via FinalizeContext::all_attrs, so it can reject incompatible combinations. attr_span is the span of the first attribute that was encountered.

Defaults to a no-op.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl CombineAttributeParser for AllowInternalUnstableParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability

type Item = (Symbol, Span)

impl CombineAttributeParser for CrateTypeParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability = AttributeStability::Stable

type Item = CrateType

impl CombineAttributeParser for DebuggerVisualizerParser

const PATH: &[Symbol]

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability = AttributeStability::Stable

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

type Item = DebugVisualizer

impl CombineAttributeParser for FeatureParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind = AttributeKind::Feature

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability = AttributeStability::Stable

type Item = Ident

impl CombineAttributeParser for ForceTargetFeatureParser

const PATH: &[Symbol]

const SAFETY: AttributeSafety

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const TEMPLATE: AttributeTemplate

const ALLOWED_TARGETS: AllowedTargets<'_>

const STABILITY: AttributeStability

type Item = (Symbol, Span)

impl CombineAttributeParser for LinkParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind = AttributeKind::Link

const TEMPLATE: AttributeTemplate

const ALLOWED_TARGETS: AllowedTargets<'_>

const STABILITY: AttributeStability = AttributeStability::Stable

type Item = LinkEntry

impl CombineAttributeParser for RegisterToolParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability

type Item = Ident

impl CombineAttributeParser for ReprParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const TEMPLATE: AttributeTemplate

const ALLOWED_TARGETS: AllowedTargets<'_> = AllowedTargets::ManuallyChecked

const STABILITY: AttributeStability = AttributeStability::Stable

type Item = (ReprAttr, Span)

impl CombineAttributeParser for RustcAllowConstFnUnstableParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability

type Item = Symbol

impl CombineAttributeParser for RustcCleanParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const ALLOWED_TARGETS: AllowedTargets<'_>

const STABILITY: AttributeStability

const TEMPLATE: AttributeTemplate

type Item = RustcCleanAttribute

impl CombineAttributeParser for RustcDumpLayoutParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability

type Item = RustcDumpLayoutKind

impl CombineAttributeParser for RustcMirParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability

type Item = RustcMirKind

impl CombineAttributeParser for RustcThenThisWouldNeedParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability

type Item = Ident

impl CombineAttributeParser for TargetFeatureParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const TEMPLATE: AttributeTemplate

const ALLOWED_TARGETS: AllowedTargets<'_>

const STABILITY: AttributeStability = AttributeStability::Stable

type Item = (Symbol, Span)

impl CombineAttributeParser for UnstableFeatureBoundParser

const PATH: &[Symbol]

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

const STABILITY: AttributeStability

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

type Item = (Symbol, Span)

impl CombineAttributeParser for UnstableRemovedParser

const PATH: &[Symbol]

const ALLOWED_TARGETS: AllowedTargets<'_>

const TEMPLATE: AttributeTemplate

const STABILITY: AttributeStability

const CONVERT: fn(ThinVec<Self::Item>, Span) -> AttributeKind

type Item = UnstableRemovedFeature