Enum Attribute

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

Variants

Parsed(AttributeKind)

A parsed built-in attribute.

Each attribute has a span connected to it. However, you must be somewhat careful using it. That’s because sometimes we merge multiple attributes together, like when an item has multiple repr attributes. In this case the span might not be very useful.

Unparsed(Box<AttrItem>)

An attribute that could not be parsed, out of a token-like representation. This is the case for custom tool attributes.

Implementations

impl Attribute

pub fn get_normal_item(&self) -> &AttrItem

pub fn unwrap_normal_item(self) -> AttrItem

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

impl Attribute

pub fn id(&self) -> AttrId

pub fn name_or_empty(&self) -> Symbol

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

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

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

pub fn ident(&self) -> Option<Ident>

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

pub fn is_doc_comment(&self) -> bool

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

pub fn span(&self) -> Span

pub fn is_word(&self) -> bool

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

pub fn ident_path(&self) -> Option<SmallVec<[Ident; 1]>>

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

pub fn is_proc_macro_attr(&self) -> bool

pub fn doc_str_and_comment_kind(&self) -> Option<(Symbol, CommentKind)>

pub fn style(&self) -> AttrStyle

Trait Implementations

impl<'tcx> ArenaAllocatable<'tcx> for Attribute

fn allocate_on(self, arena: &'tcx Arena<'tcx>) -> &'tcx mut Self

fn allocate_from_iter( arena: &'tcx Arena<'tcx>, iter: impl IntoIterator<Item = Self>, ) -> &'tcx mut [Self]

impl AttributeExt for Attribute

fn ident(&self) -> Option<Ident>

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

fn id(&self) -> AttrId

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) -> bool

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 span(&self) -> Span

get the span of the entire attribute

fn is_word(&self) -> bool

fn ident_path(&self) -> Option<SmallVec<[Ident; 1]>>

Returns None for doc comments

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

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

fn doc_str_and_comment_kind(&self) -> Option<(Symbol, CommentKind)>

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

fn style(&self) -> AttrStyle

fn name_or_empty(&self) -> Symbol

For a single-segment attribute (i.e., #[attr] and not #[path::atrr]), return the name of the attribute, else return the empty identifier.

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

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

fn is_proc_macro_attr(&self) -> bool

impl Clone for Attribute

fn clone(&self) -> Attribute

Returns a copy 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<__CTX> HashStable<__CTX> for Attribute

where __CTX: HashStableContext,

fn hash_stable(&self, __hcx: &mut __CTX, __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: 32 bytes

Size for each variant:

• Parsed: 32 bytes
• Unparsed: 16 bytes