Struct Attribute

pub struct Attribute {
    pub kind: AttrKind,
    pub id: AttrId,
    pub style: AttrStyle,
    pub span: Span,
}

A syntax-level representation of an attribute.

Fields

kind: AttrKind

id: AttrId

style: AttrStyle

Denotes if the attribute decorates the following construct (outer) or the construct this attribute is contained within (inner).

span: Span

Implementations

impl Attribute

pub fn get_normal_item(&self) -> &AttrItem

pub fn unwrap_normal_item(self) -> AttrItem

pub 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.

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

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

pub fn name_or_empty(&self) -> Symbol

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

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

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

pub fn is_word(&self) -> bool

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

Returns a list of meta items if the attribute is delimited with parenthesis:

#[attr(a, b = "c")] // Returns `Some()`.
#[attr = ""] // Returns `None`.
#[attr] // Returns `None`.

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

Returns the string value in:

#[attribute = "value"]
              ^^^^^^^

It returns None in any other cases, including doc comments if they are not under the form #[doc = "..."].

It also returns None for:

#[attr("value")]

pub 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.

• ///doc returns Some(("doc", CommentKind::Line)).
• /** doc */ returns Some(("doc", CommentKind::Block)).
• #[doc = "doc"] returns Some(("doc", CommentKind::Line)).
• #[doc(...)] returns None.

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

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

• ///doc returns Some("doc").
• #[doc = "doc"] returns Some("doc").
• #[doc(...)] returns None.

pub fn may_have_doc_links(&self) -> bool

pub fn is_proc_macro_attr(&self) -> bool

pub fn meta(&self) -> Option<MetaItem>

Extracts the MetaItem from inside this Attribute.

pub fn meta_kind(&self) -> Option<MetaItemKind>

pub fn token_trees(&self) -> Vec<TokenTree>

Trait Implementations

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 HasAttrs for Attribute

const SUPPORTS_CUSTOM_INNER_ATTRS: bool = false

This is true if this HasAttrs might support ‘custom’ (proc-macro) inner attributes. Attributes like #![cfg] and #![cfg_attr] are not considered ‘custom’ attributes.

fn attrs(&self) -> &[Attribute]

fn visit_attrs(&mut self, _f: impl FnOnce(&mut AttrVec))

impl HasTokens for Attribute

fn tokens(&self) -> Option<&LazyAttrTokenStream>

fn tokens_mut(&mut self) -> Option<&mut Option<LazyAttrTokenStream>>

impl<AstCtx: HashStableContext> HashStable<AstCtx> for Attribute

fn hash_stable(&self, hcx: &mut AstCtx, 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