Enum Attribute 

pub enum Attribute {
    Parsed(AttributeKind),
    Tool(Box<AttrItem>),
    DeriveHelper(Box<AttrItem>),
}

A high level representation of an attribute.

Not to be confused with ast::Attribute, which represents the syntax-level form of an attribute.

Variants

Parsed(AttributeKind)

A parsed built-in attribute.

Parsed attributes don’t generally have a span associated with them. This is because multiple syntax-level attributes can be represented into a single semantic attribute. For example, an item can have multiple repr attributes on it, which will coalesce into a single AttributeKind::Repr, and the stable, unstable, and rustc_allowed_through_unstable_modules all combine into a single AttributeKind::Stability attribute. Most Attribute variants do have a Span field, though, mostly for the purpose of generating diagnostics later in the compilation process.

Tool(Box<AttrItem>)

A tool attribute.

Tool attributes, with the exception of diagnostic attributes, are not converted into a parsed form.

DeriveHelper(Box<AttrItem>)

A derive helper attribute.

Derive helper attributes serve no use beyond macro expansion, but they are useful to consumers of rustdoc-json, so we keep them around. See https://github.com/rust-lang/rust/issues/157107 for context.

Implementations

impl Attribute

pub fn value_lit(&self) -> Option<&MetaItemLit>

pub fn is_prefix_attr_for_suggestions(&self) -> bool

Trait Implementations

impl AttributeExt for Attribute

fn name(&self) -> Option<Symbol>

For a single-segment attribute, returns its name; otherwise, returns None.

fn meta_item_list(&self) -> Option<ThinVec<MetaItemInner>>

Get the meta item list, #[attr(meta item list)]

fn value_str(&self) -> Option<Symbol>

Gets the value literal, as string, when using #[attr = value]

fn value_span(&self) -> Option<Span>

Gets the span of the value literal, as string, when using #[attr = value]

fn path_matches(&self, name: &[Symbol]) -> bool

Checks whether the path of this attribute matches the name.

fn is_doc_comment(&self) -> Option<Span>

Returns true if it is a sugared doc comment (/// or //! for example). So #[doc = "doc"] (which is a doc comment) and #[doc(...)] (which is not a doc comment) will return false.

fn is_word(&self) -> bool

Returns whether the attribute is a path, without any arguments.

fn symbol_path(&self) -> Option<SmallVec<[Symbol; 1]>>

Returns None for doc comments

fn path_span(&self) -> Option<Span>

fn doc_str(&self) -> Option<Symbol>

Returns the documentation if this is a doc comment or a sugared doc comment.

fn doc_str_and_fragment_kind(&self) -> Option<(Symbol, DocFragmentKind, Span)>

Returns the documentation and its kind if this is a doc comment or a sugared doc comment.

fn doc_resolution_scope(&self) -> Option<AttrStyle>

Returns outer or inner if this is a doc attribute or a sugared doc comment, otherwise None.

fn is_proc_macro_attr(&self) -> bool

Returns whether this attribute is any of the proc macro attributes. i.e. proc_macro, proc_macro_attribute or proc_macro_derive.

fn is_doc_keyword_or_attribute(&self) -> bool

Returns true is this attribute contains doc(keyword) or doc(attribute).

fn is_rustc_doc_primitive(&self) -> bool

Returns true if this is a #[rustc_doc_primitive] attribute.

fn has_name(&self, name: Symbol) -> bool

Returns true if the attribute’s first and only path segment is equal to the passed-in symbol.

fn has_any_name(&self, names: &[Symbol]) -> bool

Returns true if the attribute’s first and only path segment is any of the passed-in symbols.

fn path(&self) -> SmallVec<[Symbol; 1]>

impl Clone for Attribute

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Attribute

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

Formats the value using the given formatter.

impl<__D: SpanDecoder> Decodable<__D> for Attribute

fn decode(__decoder: &mut __D) -> Self

impl<__E: SpanEncoder> Encodable<__E> for Attribute

fn encode(&self, __encoder: &mut __E)

impl StableHash for Attribute

fn stable_hash<__Hcx: StableHashCtxt>( &self, __hcx: &mut __Hcx, __hasher: &mut StableHasher, )

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 40 bytes

Size for each variant:

• Parsed: 40 bytes
• Tool: 16 bytes
• DeriveHelper: 16 bytes