1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! Functions dealing with attributes and meta items
15 pub use self::builtin::{
16 cfg_matches, contains_feature_attr, eval_condition, find_crate_name, find_deprecation,
17 find_repr_attrs, find_stability, find_unwind_attr, Deprecation, InlineAttr, IntType, ReprAttr,
18 RustcConstUnstable, RustcDeprecation, Stability, StabilityLevel, UnwindAttr,
20 pub use self::IntType::*;
21 pub use self::ReprAttr::*;
22 pub use self::StabilityLevel::*;
25 use ast::{AttrId, Attribute, Name, Ident, Path, PathSegment};
26 use ast::{MetaItem, MetaItemKind, NestedMetaItem, NestedMetaItemKind};
27 use ast::{Lit, LitKind, Expr, ExprKind, Item, Local, Stmt, StmtKind, GenericParam};
28 use codemap::{BytePos, Spanned, respan, dummy_spanned};
30 use parse::lexer::comments::{doc_comment_style, strip_doc_comment_decoration};
31 use parse::parser::Parser;
32 use parse::{self, ParseSess, PResult};
33 use parse::token::{self, Token};
36 use tokenstream::{TokenStream, TokenTree, Delimited};
42 pub fn mark_used(attr: &Attribute) {
43 debug!("Marking {:?} as used.", attr);
44 let AttrId(id) = attr.id;
45 GLOBALS.with(|globals| {
46 let mut slot = globals.used_attrs.lock();
47 let idx = (id / 64) as usize;
49 if slot.len() <= idx {
50 slot.resize(idx + 1, 0);
52 slot[idx] |= 1 << shift;
56 pub fn is_used(attr: &Attribute) -> bool {
57 let AttrId(id) = attr.id;
58 GLOBALS.with(|globals| {
59 let slot = globals.used_attrs.lock();
60 let idx = (id / 64) as usize;
62 slot.get(idx).map(|bits| bits & (1 << shift) != 0)
67 pub fn mark_known(attr: &Attribute) {
68 debug!("Marking {:?} as known.", attr);
69 let AttrId(id) = attr.id;
70 GLOBALS.with(|globals| {
71 let mut slot = globals.known_attrs.lock();
72 let idx = (id / 64) as usize;
74 if slot.len() <= idx {
75 slot.resize(idx + 1, 0);
77 slot[idx] |= 1 << shift;
81 pub fn is_known(attr: &Attribute) -> bool {
82 let AttrId(id) = attr.id;
83 GLOBALS.with(|globals| {
84 let slot = globals.known_attrs.lock();
85 let idx = (id / 64) as usize;
87 slot.get(idx).map(|bits| bits & (1 << shift) != 0)
92 const RUST_KNOWN_TOOL: &[&str] = &["clippy", "rustfmt"];
94 pub fn is_known_tool(attr: &Attribute) -> bool {
96 attr.path.segments.iter().next().expect("empty path in attribute").ident.name;
97 RUST_KNOWN_TOOL.contains(&tool_name.as_str().as_ref())
100 impl NestedMetaItem {
101 /// Returns the MetaItem if self is a NestedMetaItemKind::MetaItem.
102 pub fn meta_item(&self) -> Option<&MetaItem> {
104 NestedMetaItemKind::MetaItem(ref item) => Some(item),
109 /// Returns the Lit if self is a NestedMetaItemKind::Literal.
110 pub fn literal(&self) -> Option<&Lit> {
112 NestedMetaItemKind::Literal(ref lit) => Some(lit),
117 /// Returns the Span for `self`.
118 pub fn span(&self) -> Span {
122 /// Returns true if this list item is a MetaItem with a name of `name`.
123 pub fn check_name(&self, name: &str) -> bool {
124 self.meta_item().map_or(false, |meta_item| meta_item.check_name(name))
127 /// Returns the name of the meta item, e.g. `foo` in `#[foo]`,
128 /// `#[foo="bar"]` and `#[foo(bar)]`, if self is a MetaItem
129 pub fn name(&self) -> Option<Name> {
130 self.meta_item().and_then(|meta_item| Some(meta_item.name()))
133 /// Gets the string value if self is a MetaItem and the MetaItem is a
134 /// MetaItemKind::NameValue variant containing a string, otherwise None.
135 pub fn value_str(&self) -> Option<Symbol> {
136 self.meta_item().and_then(|meta_item| meta_item.value_str())
139 /// Returns a name and single literal value tuple of the MetaItem.
140 pub fn name_value_literal(&self) -> Option<(Name, &Lit)> {
141 self.meta_item().and_then(
142 |meta_item| meta_item.meta_item_list().and_then(
144 if meta_item_list.len() == 1 {
145 let nested_item = &meta_item_list[0];
146 if nested_item.is_literal() {
147 Some((meta_item.name(), nested_item.literal().unwrap()))
157 /// Returns a MetaItem if self is a MetaItem with Kind Word.
158 pub fn word(&self) -> Option<&MetaItem> {
159 self.meta_item().and_then(|meta_item| if meta_item.is_word() {
166 /// Gets a list of inner meta items from a list MetaItem type.
167 pub fn meta_item_list(&self) -> Option<&[NestedMetaItem]> {
168 self.meta_item().and_then(|meta_item| meta_item.meta_item_list())
171 /// Returns `true` if the variant is MetaItem.
172 pub fn is_meta_item(&self) -> bool {
173 self.meta_item().is_some()
176 /// Returns `true` if the variant is Literal.
177 pub fn is_literal(&self) -> bool {
178 self.literal().is_some()
181 /// Returns `true` if self is a MetaItem and the meta item is a word.
182 pub fn is_word(&self) -> bool {
183 self.word().is_some()
186 /// Returns `true` if self is a MetaItem and the meta item is a ValueString.
187 pub fn is_value_str(&self) -> bool {
188 self.value_str().is_some()
191 /// Returns `true` if self is a MetaItem and the meta item is a list.
192 pub fn is_meta_item_list(&self) -> bool {
193 self.meta_item_list().is_some()
197 fn name_from_path(path: &Path) -> Name {
198 path.segments.last().expect("empty path in attribute").ident.name
202 pub fn check_name(&self, name: &str) -> bool {
203 let matches = self.path == name;
210 /// Returns the **last** segment of the name of this attribute.
211 /// E.g. `foo` for `#[foo]`, `skip` for `#[rustfmt::skip]`.
212 pub fn name(&self) -> Name {
213 name_from_path(&self.path)
216 pub fn value_str(&self) -> Option<Symbol> {
217 self.meta().and_then(|meta| meta.value_str())
220 pub fn meta_item_list(&self) -> Option<Vec<NestedMetaItem>> {
222 Some(MetaItem { node: MetaItemKind::List(list), .. }) => Some(list),
227 pub fn is_word(&self) -> bool {
228 self.path.segments.len() == 1 && self.tokens.is_empty()
231 pub fn span(&self) -> Span {
235 pub fn is_meta_item_list(&self) -> bool {
236 self.meta_item_list().is_some()
239 /// Indicates if the attribute is a Value String.
240 pub fn is_value_str(&self) -> bool {
241 self.value_str().is_some()
244 pub fn is_scoped(&self) -> bool {
245 self.path.segments.len() > 1
250 pub fn name(&self) -> Name {
251 name_from_path(&self.ident)
254 pub fn value_str(&self) -> Option<Symbol> {
256 MetaItemKind::NameValue(ref v) => {
258 LitKind::Str(ref s, _) => Some(*s),
266 pub fn meta_item_list(&self) -> Option<&[NestedMetaItem]> {
268 MetaItemKind::List(ref l) => Some(&l[..]),
273 pub fn is_word(&self) -> bool {
275 MetaItemKind::Word => true,
280 pub fn span(&self) -> Span { self.span }
282 pub fn check_name(&self, name: &str) -> bool {
286 pub fn is_value_str(&self) -> bool {
287 self.value_str().is_some()
290 pub fn is_meta_item_list(&self) -> bool {
291 self.meta_item_list().is_some()
296 /// Extract the MetaItem from inside this Attribute.
297 pub fn meta(&self) -> Option<MetaItem> {
298 let mut tokens = self.tokens.trees().peekable();
300 ident: self.path.clone(),
301 node: if let Some(node) = MetaItemKind::from_tokens(&mut tokens) {
302 if tokens.peek().is_some() {
313 pub fn parse<'a, T, F>(&self, sess: &'a ParseSess, mut f: F) -> PResult<'a, T>
314 where F: FnMut(&mut Parser<'a>) -> PResult<'a, T>,
316 let mut parser = Parser::new(sess, self.tokens.clone(), None, false, false);
317 let result = f(&mut parser)?;
318 if parser.token != token::Eof {
319 parser.unexpected()?;
324 pub fn parse_list<'a, T, F>(&self, sess: &'a ParseSess, mut f: F) -> PResult<'a, Vec<T>>
325 where F: FnMut(&mut Parser<'a>) -> PResult<'a, T>,
327 if self.tokens.is_empty() {
328 return Ok(Vec::new());
330 self.parse(sess, |parser| {
331 parser.expect(&token::OpenDelim(token::Paren))?;
332 let mut list = Vec::new();
333 while !parser.eat(&token::CloseDelim(token::Paren)) {
334 list.push(f(parser)?);
335 if !parser.eat(&token::Comma) {
336 parser.expect(&token::CloseDelim(token::Paren))?;
344 pub fn parse_meta<'a>(&self, sess: &'a ParseSess) -> PResult<'a, MetaItem> {
346 ident: self.path.clone(),
347 node: self.parse(sess, |parser| parser.parse_meta_item_kind())?,
352 /// Convert self to a normal #[doc="foo"] comment, if it is a
353 /// comment like `///` or `/** */`. (Returns self unchanged for
354 /// non-sugared doc attributes.)
355 pub fn with_desugared_doc<T, F>(&self, f: F) -> T where
356 F: FnOnce(&Attribute) -> T,
358 if self.is_sugared_doc {
359 let comment = self.value_str().unwrap();
360 let meta = mk_name_value_item_str(
361 Ident::from_str("doc"),
362 dummy_spanned(Symbol::intern(&strip_doc_comment_decoration(&comment.as_str()))));
363 let mut attr = if self.style == ast::AttrStyle::Outer {
364 mk_attr_outer(self.span, self.id, meta)
366 mk_attr_inner(self.span, self.id, meta)
368 attr.is_sugared_doc = true;
378 pub fn mk_name_value_item_str(ident: Ident, value: Spanned<Symbol>) -> MetaItem {
379 let value = respan(value.span, LitKind::Str(value.node, ast::StrStyle::Cooked));
380 mk_name_value_item(ident.span.to(value.span), ident, value)
383 pub fn mk_name_value_item(span: Span, ident: Ident, value: ast::Lit) -> MetaItem {
384 MetaItem { ident: Path::from_ident(ident), span, node: MetaItemKind::NameValue(value) }
387 pub fn mk_list_item(span: Span, ident: Ident, items: Vec<NestedMetaItem>) -> MetaItem {
388 MetaItem { ident: Path::from_ident(ident), span, node: MetaItemKind::List(items) }
391 pub fn mk_word_item(ident: Ident) -> MetaItem {
392 MetaItem { ident: Path::from_ident(ident), span: ident.span, node: MetaItemKind::Word }
395 pub fn mk_nested_word_item(ident: Ident) -> NestedMetaItem {
396 respan(ident.span, NestedMetaItemKind::MetaItem(mk_word_item(ident)))
399 pub fn mk_attr_id() -> AttrId {
400 use std::sync::atomic::AtomicUsize;
401 use std::sync::atomic::Ordering;
403 static NEXT_ATTR_ID: AtomicUsize = AtomicUsize::new(0);
405 let id = NEXT_ATTR_ID.fetch_add(1, Ordering::SeqCst);
406 assert!(id != ::std::usize::MAX);
410 /// Returns an inner attribute with the given value.
411 pub fn mk_attr_inner(span: Span, id: AttrId, item: MetaItem) -> Attribute {
412 mk_spanned_attr_inner(span, id, item)
415 /// Returns an inner attribute with the given value and span.
416 pub fn mk_spanned_attr_inner(sp: Span, id: AttrId, item: MetaItem) -> Attribute {
419 style: ast::AttrStyle::Inner,
421 tokens: item.node.tokens(item.span),
422 is_sugared_doc: false,
427 /// Returns an outer attribute with the given value.
428 pub fn mk_attr_outer(span: Span, id: AttrId, item: MetaItem) -> Attribute {
429 mk_spanned_attr_outer(span, id, item)
432 /// Returns an outer attribute with the given value and span.
433 pub fn mk_spanned_attr_outer(sp: Span, id: AttrId, item: MetaItem) -> Attribute {
436 style: ast::AttrStyle::Outer,
438 tokens: item.node.tokens(item.span),
439 is_sugared_doc: false,
444 pub fn mk_sugared_doc_attr(id: AttrId, text: Symbol, span: Span) -> Attribute {
445 let style = doc_comment_style(&text.as_str());
446 let lit = respan(span, LitKind::Str(text, ast::StrStyle::Cooked));
450 path: Path::from_ident(Ident::from_str("doc").with_span_pos(span)),
451 tokens: MetaItemKind::NameValue(lit).tokens(span),
452 is_sugared_doc: true,
457 pub fn list_contains_name(items: &[NestedMetaItem], name: &str) -> bool {
458 items.iter().any(|item| {
459 item.check_name(name)
463 pub fn contains_name(attrs: &[Attribute], name: &str) -> bool {
464 attrs.iter().any(|item| {
465 item.check_name(name)
469 pub fn find_by_name<'a>(attrs: &'a [Attribute], name: &str) -> Option<&'a Attribute> {
470 attrs.iter().find(|attr| attr.check_name(name))
473 pub fn first_attr_value_str_by_name(attrs: &[Attribute], name: &str) -> Option<Symbol> {
475 .find(|at| at.check_name(name))
476 .and_then(|at| at.value_str())
480 fn tokens(&self) -> TokenStream {
481 let mut idents = vec![];
482 let mut last_pos = BytePos(0 as u32);
483 for (i, segment) in self.ident.segments.iter().enumerate() {
484 let is_first = i == 0;
486 let mod_sep_span = Span::new(last_pos,
487 segment.ident.span.lo(),
488 segment.ident.span.ctxt());
489 idents.push(TokenTree::Token(mod_sep_span, Token::ModSep).into());
491 idents.push(TokenTree::Token(segment.ident.span,
492 Token::from_ast_ident(segment.ident)).into());
493 last_pos = segment.ident.span.hi();
495 idents.push(self.node.tokens(self.span));
496 TokenStream::concat(idents)
499 fn from_tokens<I>(tokens: &mut iter::Peekable<I>) -> Option<MetaItem>
500 where I: Iterator<Item = TokenTree>,
502 // FIXME: Share code with `parse_path`.
503 let ident = match tokens.next() {
504 Some(TokenTree::Token(span, Token::Ident(ident, _))) => {
505 if let Some(TokenTree::Token(_, Token::ModSep)) = tokens.peek() {
506 let mut segments = vec![PathSegment::from_ident(ident.with_span_pos(span))];
509 if let Some(TokenTree::Token(span,
510 Token::Ident(ident, _))) = tokens.next() {
511 segments.push(PathSegment::from_ident(ident.with_span_pos(span)));
515 if let Some(TokenTree::Token(_, Token::ModSep)) = tokens.peek() {
521 let span = span.with_hi(segments.last().unwrap().ident.span.hi());
522 Path { span, segments }
524 Path::from_ident(ident.with_span_pos(span))
527 Some(TokenTree::Token(_, Token::Interpolated(ref nt))) => match nt.0 {
528 token::Nonterminal::NtIdent(ident, _) => Path::from_ident(ident),
529 token::Nonterminal::NtMeta(ref meta) => return Some(meta.clone()),
530 token::Nonterminal::NtPath(ref path) => path.clone(),
535 let list_closing_paren_pos = tokens.peek().map(|tt| tt.span().hi());
536 let node = MetaItemKind::from_tokens(tokens)?;
537 let hi = match node {
538 MetaItemKind::NameValue(ref lit) => lit.span.hi(),
539 MetaItemKind::List(..) => list_closing_paren_pos.unwrap_or(ident.span.hi()),
540 _ => ident.span.hi(),
542 let span = ident.span.with_hi(hi);
543 Some(MetaItem { ident, node, span })
548 pub fn tokens(&self, span: Span) -> TokenStream {
550 MetaItemKind::Word => TokenStream::empty(),
551 MetaItemKind::NameValue(ref lit) => {
552 TokenStream::concat(vec![TokenTree::Token(span, Token::Eq).into(), lit.tokens()])
554 MetaItemKind::List(ref list) => {
555 let mut tokens = Vec::new();
556 for (i, item) in list.iter().enumerate() {
558 tokens.push(TokenTree::Token(span, Token::Comma).into());
560 tokens.push(item.node.tokens());
562 TokenTree::Delimited(span, Delimited {
564 tts: TokenStream::concat(tokens).into(),
570 fn from_tokens<I>(tokens: &mut iter::Peekable<I>) -> Option<MetaItemKind>
571 where I: Iterator<Item = TokenTree>,
573 let delimited = match tokens.peek().cloned() {
574 Some(TokenTree::Token(_, token::Eq)) => {
576 return if let Some(TokenTree::Token(span, token)) = tokens.next() {
577 LitKind::from_token(token)
578 .map(|lit| MetaItemKind::NameValue(Spanned { node: lit, span: span }))
583 Some(TokenTree::Delimited(_, ref delimited)) if delimited.delim == token::Paren => {
587 _ => return Some(MetaItemKind::Word),
590 let mut tokens = delimited.into_trees().peekable();
591 let mut result = Vec::new();
592 while let Some(..) = tokens.peek() {
593 let item = NestedMetaItemKind::from_tokens(&mut tokens)?;
594 result.push(respan(item.span(), item));
595 match tokens.next() {
596 None | Some(TokenTree::Token(_, Token::Comma)) => {}
600 Some(MetaItemKind::List(result))
604 impl NestedMetaItemKind {
605 fn span(&self) -> Span {
607 NestedMetaItemKind::MetaItem(ref item) => item.span,
608 NestedMetaItemKind::Literal(ref lit) => lit.span,
612 fn tokens(&self) -> TokenStream {
614 NestedMetaItemKind::MetaItem(ref item) => item.tokens(),
615 NestedMetaItemKind::Literal(ref lit) => lit.tokens(),
619 fn from_tokens<I>(tokens: &mut iter::Peekable<I>) -> Option<NestedMetaItemKind>
620 where I: Iterator<Item = TokenTree>,
622 if let Some(TokenTree::Token(span, token)) = tokens.peek().cloned() {
623 if let Some(node) = LitKind::from_token(token) {
625 return Some(NestedMetaItemKind::Literal(respan(span, node)));
629 MetaItem::from_tokens(tokens).map(NestedMetaItemKind::MetaItem)
634 fn tokens(&self) -> TokenStream {
635 TokenTree::Token(self.span, self.node.token()).into()
640 fn token(&self) -> Token {
644 LitKind::Str(string, ast::StrStyle::Cooked) => {
645 let escaped = string.as_str().escape_default();
646 Token::Literal(token::Lit::Str_(Symbol::intern(&escaped)), None)
648 LitKind::Str(string, ast::StrStyle::Raw(n)) => {
649 Token::Literal(token::Lit::StrRaw(string, n), None)
651 LitKind::ByteStr(ref bytes) => {
652 let string = bytes.iter().cloned().flat_map(ascii::escape_default)
653 .map(Into::<char>::into).collect::<String>();
654 Token::Literal(token::Lit::ByteStr(Symbol::intern(&string)), None)
656 LitKind::Byte(byte) => {
657 let string: String = ascii::escape_default(byte).map(Into::<char>::into).collect();
658 Token::Literal(token::Lit::Byte(Symbol::intern(&string)), None)
660 LitKind::Char(ch) => {
661 let string: String = ch.escape_default().map(Into::<char>::into).collect();
662 Token::Literal(token::Lit::Char(Symbol::intern(&string)), None)
664 LitKind::Int(n, ty) => {
665 let suffix = match ty {
666 ast::LitIntType::Unsigned(ty) => Some(Symbol::intern(ty.ty_to_string())),
667 ast::LitIntType::Signed(ty) => Some(Symbol::intern(ty.ty_to_string())),
668 ast::LitIntType::Unsuffixed => None,
670 Token::Literal(token::Lit::Integer(Symbol::intern(&n.to_string())), suffix)
672 LitKind::Float(symbol, ty) => {
673 Token::Literal(token::Lit::Float(symbol), Some(Symbol::intern(ty.ty_to_string())))
675 LitKind::FloatUnsuffixed(symbol) => Token::Literal(token::Lit::Float(symbol), None),
676 LitKind::Bool(value) => Token::Ident(Ident::with_empty_ctxt(Symbol::intern(if value {
684 fn from_token(token: Token) -> Option<LitKind> {
686 Token::Ident(ident, false) if ident.name == "true" => Some(LitKind::Bool(true)),
687 Token::Ident(ident, false) if ident.name == "false" => Some(LitKind::Bool(false)),
688 Token::Interpolated(ref nt) => match nt.0 {
689 token::NtExpr(ref v) | token::NtLiteral(ref v) => match v.node {
690 ExprKind::Lit(ref lit) => Some(lit.node.clone()),
695 Token::Literal(lit, suf) => {
696 let (suffix_illegal, result) = parse::lit_token(lit, suf, None);
697 if suffix_illegal && suf.is_some() {
707 pub trait HasAttrs: Sized {
708 fn attrs(&self) -> &[ast::Attribute];
709 fn map_attrs<F: FnOnce(Vec<ast::Attribute>) -> Vec<ast::Attribute>>(self, f: F) -> Self;
712 impl<T: HasAttrs> HasAttrs for Spanned<T> {
713 fn attrs(&self) -> &[ast::Attribute] { self.node.attrs() }
714 fn map_attrs<F: FnOnce(Vec<ast::Attribute>) -> Vec<ast::Attribute>>(self, f: F) -> Self {
715 respan(self.span, self.node.map_attrs(f))
719 impl HasAttrs for Vec<Attribute> {
720 fn attrs(&self) -> &[Attribute] {
723 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(self, f: F) -> Self {
728 impl HasAttrs for ThinVec<Attribute> {
729 fn attrs(&self) -> &[Attribute] {
732 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(self, f: F) -> Self {
733 f(self.into()).into()
737 impl<T: HasAttrs + 'static> HasAttrs for P<T> {
738 fn attrs(&self) -> &[Attribute] {
741 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(self, f: F) -> Self {
742 self.map(|t| t.map_attrs(f))
746 impl HasAttrs for StmtKind {
747 fn attrs(&self) -> &[Attribute] {
749 StmtKind::Local(ref local) => local.attrs(),
750 StmtKind::Item(..) => &[],
751 StmtKind::Expr(ref expr) | StmtKind::Semi(ref expr) => expr.attrs(),
752 StmtKind::Mac(ref mac) => {
753 let (_, _, ref attrs) = **mac;
759 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(self, f: F) -> Self {
761 StmtKind::Local(local) => StmtKind::Local(local.map_attrs(f)),
762 StmtKind::Item(..) => self,
763 StmtKind::Expr(expr) => StmtKind::Expr(expr.map_attrs(f)),
764 StmtKind::Semi(expr) => StmtKind::Semi(expr.map_attrs(f)),
765 StmtKind::Mac(mac) => StmtKind::Mac(mac.map(|(mac, style, attrs)| {
766 (mac, style, attrs.map_attrs(f))
772 impl HasAttrs for Stmt {
773 fn attrs(&self) -> &[ast::Attribute] { self.node.attrs() }
774 fn map_attrs<F: FnOnce(Vec<ast::Attribute>) -> Vec<ast::Attribute>>(self, f: F) -> Self {
775 Stmt { id: self.id, node: self.node.map_attrs(f), span: self.span }
779 impl HasAttrs for GenericParam {
780 fn attrs(&self) -> &[ast::Attribute] {
784 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(mut self, f: F) -> Self {
785 self.attrs = self.attrs.map_attrs(f);
790 macro_rules! derive_has_attrs {
791 ($($ty:path),*) => { $(
792 impl HasAttrs for $ty {
793 fn attrs(&self) -> &[Attribute] {
797 fn map_attrs<F>(mut self, f: F) -> Self
798 where F: FnOnce(Vec<Attribute>) -> Vec<Attribute>,
800 self.attrs = self.attrs.map_attrs(f);
808 Item, Expr, Local, ast::ForeignItem, ast::StructField, ast::ImplItem, ast::TraitItem, ast::Arm,
809 ast::Field, ast::FieldPat, ast::Variant_