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"];
93 const RUST_KNOWN_LINT_TOOL: &[&str] = &["clippy"];
95 pub fn is_known_tool(attr: &Attribute) -> bool {
97 attr.path.segments.iter().next().expect("empty path in attribute").ident.name;
98 RUST_KNOWN_TOOL.contains(&tool_name.as_str().as_ref())
101 pub fn is_known_lint_tool(m_item: Ident) -> bool {
102 RUST_KNOWN_LINT_TOOL.contains(&m_item.as_str().as_ref())
105 impl NestedMetaItem {
106 /// Returns the MetaItem if self is a NestedMetaItemKind::MetaItem.
107 pub fn meta_item(&self) -> Option<&MetaItem> {
109 NestedMetaItemKind::MetaItem(ref item) => Some(item),
114 /// Returns the Lit if self is a NestedMetaItemKind::Literal.
115 pub fn literal(&self) -> Option<&Lit> {
117 NestedMetaItemKind::Literal(ref lit) => Some(lit),
122 /// Returns the Span for `self`.
123 pub fn span(&self) -> Span {
127 /// Returns true if this list item is a MetaItem with a name of `name`.
128 pub fn check_name(&self, name: &str) -> bool {
129 self.meta_item().map_or(false, |meta_item| meta_item.check_name(name))
132 /// Returns the name of the meta item, e.g. `foo` in `#[foo]`,
133 /// `#[foo="bar"]` and `#[foo(bar)]`, if self is a MetaItem
134 pub fn name(&self) -> Option<Name> {
135 self.meta_item().and_then(|meta_item| Some(meta_item.name()))
138 /// Gets the string value if self is a MetaItem and the MetaItem is a
139 /// MetaItemKind::NameValue variant containing a string, otherwise None.
140 pub fn value_str(&self) -> Option<Symbol> {
141 self.meta_item().and_then(|meta_item| meta_item.value_str())
144 /// Returns a name and single literal value tuple of the MetaItem.
145 pub fn name_value_literal(&self) -> Option<(Name, &Lit)> {
146 self.meta_item().and_then(
147 |meta_item| meta_item.meta_item_list().and_then(
149 if meta_item_list.len() == 1 {
150 let nested_item = &meta_item_list[0];
151 if nested_item.is_literal() {
152 Some((meta_item.name(), nested_item.literal().unwrap()))
162 /// Returns a MetaItem if self is a MetaItem with Kind Word.
163 pub fn word(&self) -> Option<&MetaItem> {
164 self.meta_item().and_then(|meta_item| if meta_item.is_word() {
171 /// Gets a list of inner meta items from a list MetaItem type.
172 pub fn meta_item_list(&self) -> Option<&[NestedMetaItem]> {
173 self.meta_item().and_then(|meta_item| meta_item.meta_item_list())
176 /// Returns `true` if the variant is MetaItem.
177 pub fn is_meta_item(&self) -> bool {
178 self.meta_item().is_some()
181 /// Returns `true` if the variant is Literal.
182 pub fn is_literal(&self) -> bool {
183 self.literal().is_some()
186 /// Returns `true` if self is a MetaItem and the meta item is a word.
187 pub fn is_word(&self) -> bool {
188 self.word().is_some()
191 /// Returns `true` if self is a MetaItem and the meta item is a ValueString.
192 pub fn is_value_str(&self) -> bool {
193 self.value_str().is_some()
196 /// Returns `true` if self is a MetaItem and the meta item is a list.
197 pub fn is_meta_item_list(&self) -> bool {
198 self.meta_item_list().is_some()
202 fn name_from_path(path: &Path) -> Name {
203 path.segments.last().expect("empty path in attribute").ident.name
207 pub fn check_name(&self, name: &str) -> bool {
208 let matches = self.path == name;
215 /// Returns the **last** segment of the name of this attribute.
216 /// E.g. `foo` for `#[foo]`, `skip` for `#[rustfmt::skip]`.
217 pub fn name(&self) -> Name {
218 name_from_path(&self.path)
221 pub fn value_str(&self) -> Option<Symbol> {
222 self.meta().and_then(|meta| meta.value_str())
225 pub fn meta_item_list(&self) -> Option<Vec<NestedMetaItem>> {
227 Some(MetaItem { node: MetaItemKind::List(list), .. }) => Some(list),
232 pub fn is_word(&self) -> bool {
233 self.path.segments.len() == 1 && self.tokens.is_empty()
236 pub fn span(&self) -> Span {
240 pub fn is_meta_item_list(&self) -> bool {
241 self.meta_item_list().is_some()
244 /// Indicates if the attribute is a Value String.
245 pub fn is_value_str(&self) -> bool {
246 self.value_str().is_some()
249 pub fn is_scoped(&self) -> bool {
250 self.path.segments.len() > 1
255 pub fn name(&self) -> Name {
256 name_from_path(&self.ident)
259 pub fn value_str(&self) -> Option<Symbol> {
261 MetaItemKind::NameValue(ref v) => {
263 LitKind::Str(ref s, _) => Some(*s),
271 pub fn meta_item_list(&self) -> Option<&[NestedMetaItem]> {
273 MetaItemKind::List(ref l) => Some(&l[..]),
278 pub fn is_word(&self) -> bool {
280 MetaItemKind::Word => true,
285 pub fn span(&self) -> Span { self.span }
287 pub fn check_name(&self, name: &str) -> bool {
291 pub fn is_value_str(&self) -> bool {
292 self.value_str().is_some()
295 pub fn is_meta_item_list(&self) -> bool {
296 self.meta_item_list().is_some()
299 pub fn is_scoped(&self) -> Option<Ident> {
300 if self.ident.segments.len() > 1 {
301 Some(self.ident.segments[0].ident)
309 /// Extract the MetaItem from inside this Attribute.
310 pub fn meta(&self) -> Option<MetaItem> {
311 let mut tokens = self.tokens.trees().peekable();
313 ident: self.path.clone(),
314 node: if let Some(node) = MetaItemKind::from_tokens(&mut tokens) {
315 if tokens.peek().is_some() {
326 pub fn parse<'a, T, F>(&self, sess: &'a ParseSess, mut f: F) -> PResult<'a, T>
327 where F: FnMut(&mut Parser<'a>) -> PResult<'a, T>,
329 let mut parser = Parser::new(sess, self.tokens.clone(), None, false, false);
330 let result = f(&mut parser)?;
331 if parser.token != token::Eof {
332 parser.unexpected()?;
337 pub fn parse_list<'a, T, F>(&self, sess: &'a ParseSess, mut f: F) -> PResult<'a, Vec<T>>
338 where F: FnMut(&mut Parser<'a>) -> PResult<'a, T>,
340 if self.tokens.is_empty() {
341 return Ok(Vec::new());
343 self.parse(sess, |parser| {
344 parser.expect(&token::OpenDelim(token::Paren))?;
345 let mut list = Vec::new();
346 while !parser.eat(&token::CloseDelim(token::Paren)) {
347 list.push(f(parser)?);
348 if !parser.eat(&token::Comma) {
349 parser.expect(&token::CloseDelim(token::Paren))?;
357 pub fn parse_meta<'a>(&self, sess: &'a ParseSess) -> PResult<'a, MetaItem> {
359 ident: self.path.clone(),
360 node: self.parse(sess, |parser| parser.parse_meta_item_kind())?,
365 /// Convert self to a normal #[doc="foo"] comment, if it is a
366 /// comment like `///` or `/** */`. (Returns self unchanged for
367 /// non-sugared doc attributes.)
368 pub fn with_desugared_doc<T, F>(&self, f: F) -> T where
369 F: FnOnce(&Attribute) -> T,
371 if self.is_sugared_doc {
372 let comment = self.value_str().unwrap();
373 let meta = mk_name_value_item_str(
374 Ident::from_str("doc"),
375 dummy_spanned(Symbol::intern(&strip_doc_comment_decoration(&comment.as_str()))));
376 let mut attr = if self.style == ast::AttrStyle::Outer {
377 mk_attr_outer(self.span, self.id, meta)
379 mk_attr_inner(self.span, self.id, meta)
381 attr.is_sugared_doc = true;
391 pub fn mk_name_value_item_str(ident: Ident, value: Spanned<Symbol>) -> MetaItem {
392 let value = respan(value.span, LitKind::Str(value.node, ast::StrStyle::Cooked));
393 mk_name_value_item(ident.span.to(value.span), ident, value)
396 pub fn mk_name_value_item(span: Span, ident: Ident, value: ast::Lit) -> MetaItem {
397 MetaItem { ident: Path::from_ident(ident), span, node: MetaItemKind::NameValue(value) }
400 pub fn mk_list_item(span: Span, ident: Ident, items: Vec<NestedMetaItem>) -> MetaItem {
401 MetaItem { ident: Path::from_ident(ident), span, node: MetaItemKind::List(items) }
404 pub fn mk_word_item(ident: Ident) -> MetaItem {
405 MetaItem { ident: Path::from_ident(ident), span: ident.span, node: MetaItemKind::Word }
408 pub fn mk_nested_word_item(ident: Ident) -> NestedMetaItem {
409 respan(ident.span, NestedMetaItemKind::MetaItem(mk_word_item(ident)))
412 pub fn mk_attr_id() -> AttrId {
413 use std::sync::atomic::AtomicUsize;
414 use std::sync::atomic::Ordering;
416 static NEXT_ATTR_ID: AtomicUsize = AtomicUsize::new(0);
418 let id = NEXT_ATTR_ID.fetch_add(1, Ordering::SeqCst);
419 assert!(id != ::std::usize::MAX);
423 /// Returns an inner attribute with the given value.
424 pub fn mk_attr_inner(span: Span, id: AttrId, item: MetaItem) -> Attribute {
425 mk_spanned_attr_inner(span, id, item)
428 /// Returns an inner attribute with the given value and span.
429 pub fn mk_spanned_attr_inner(sp: Span, id: AttrId, item: MetaItem) -> Attribute {
432 style: ast::AttrStyle::Inner,
434 tokens: item.node.tokens(item.span),
435 is_sugared_doc: false,
440 /// Returns an outer attribute with the given value.
441 pub fn mk_attr_outer(span: Span, id: AttrId, item: MetaItem) -> Attribute {
442 mk_spanned_attr_outer(span, id, item)
445 /// Returns an outer attribute with the given value and span.
446 pub fn mk_spanned_attr_outer(sp: Span, id: AttrId, item: MetaItem) -> Attribute {
449 style: ast::AttrStyle::Outer,
451 tokens: item.node.tokens(item.span),
452 is_sugared_doc: false,
457 pub fn mk_sugared_doc_attr(id: AttrId, text: Symbol, span: Span) -> Attribute {
458 let style = doc_comment_style(&text.as_str());
459 let lit = respan(span, LitKind::Str(text, ast::StrStyle::Cooked));
463 path: Path::from_ident(Ident::from_str("doc").with_span_pos(span)),
464 tokens: MetaItemKind::NameValue(lit).tokens(span),
465 is_sugared_doc: true,
470 pub fn list_contains_name(items: &[NestedMetaItem], name: &str) -> bool {
471 items.iter().any(|item| {
472 item.check_name(name)
476 pub fn contains_name(attrs: &[Attribute], name: &str) -> bool {
477 attrs.iter().any(|item| {
478 item.check_name(name)
482 pub fn find_by_name<'a>(attrs: &'a [Attribute], name: &str) -> Option<&'a Attribute> {
483 attrs.iter().find(|attr| attr.check_name(name))
486 pub fn first_attr_value_str_by_name(attrs: &[Attribute], name: &str) -> Option<Symbol> {
488 .find(|at| at.check_name(name))
489 .and_then(|at| at.value_str())
493 fn tokens(&self) -> TokenStream {
494 let mut idents = vec![];
495 let mut last_pos = BytePos(0 as u32);
496 for (i, segment) in self.ident.segments.iter().enumerate() {
497 let is_first = i == 0;
499 let mod_sep_span = Span::new(last_pos,
500 segment.ident.span.lo(),
501 segment.ident.span.ctxt());
502 idents.push(TokenTree::Token(mod_sep_span, Token::ModSep).into());
504 idents.push(TokenTree::Token(segment.ident.span,
505 Token::from_ast_ident(segment.ident)).into());
506 last_pos = segment.ident.span.hi();
508 idents.push(self.node.tokens(self.span));
509 TokenStream::concat(idents)
512 fn from_tokens<I>(tokens: &mut iter::Peekable<I>) -> Option<MetaItem>
513 where I: Iterator<Item = TokenTree>,
515 // FIXME: Share code with `parse_path`.
516 let ident = match tokens.next() {
517 Some(TokenTree::Token(span, Token::Ident(ident, _))) => {
518 if let Some(TokenTree::Token(_, Token::ModSep)) = tokens.peek() {
519 let mut segments = vec![PathSegment::from_ident(ident.with_span_pos(span))];
522 if let Some(TokenTree::Token(span,
523 Token::Ident(ident, _))) = tokens.next() {
524 segments.push(PathSegment::from_ident(ident.with_span_pos(span)));
528 if let Some(TokenTree::Token(_, Token::ModSep)) = tokens.peek() {
534 let span = span.with_hi(segments.last().unwrap().ident.span.hi());
535 Path { span, segments }
537 Path::from_ident(ident.with_span_pos(span))
540 Some(TokenTree::Token(_, Token::Interpolated(ref nt))) => match nt.0 {
541 token::Nonterminal::NtIdent(ident, _) => Path::from_ident(ident),
542 token::Nonterminal::NtMeta(ref meta) => return Some(meta.clone()),
543 token::Nonterminal::NtPath(ref path) => path.clone(),
548 let list_closing_paren_pos = tokens.peek().map(|tt| tt.span().hi());
549 let node = MetaItemKind::from_tokens(tokens)?;
550 let hi = match node {
551 MetaItemKind::NameValue(ref lit) => lit.span.hi(),
552 MetaItemKind::List(..) => list_closing_paren_pos.unwrap_or(ident.span.hi()),
553 _ => ident.span.hi(),
555 let span = ident.span.with_hi(hi);
556 Some(MetaItem { ident, node, span })
561 pub fn tokens(&self, span: Span) -> TokenStream {
563 MetaItemKind::Word => TokenStream::empty(),
564 MetaItemKind::NameValue(ref lit) => {
565 TokenStream::concat(vec![TokenTree::Token(span, Token::Eq).into(), lit.tokens()])
567 MetaItemKind::List(ref list) => {
568 let mut tokens = Vec::new();
569 for (i, item) in list.iter().enumerate() {
571 tokens.push(TokenTree::Token(span, Token::Comma).into());
573 tokens.push(item.node.tokens());
575 TokenTree::Delimited(span, Delimited {
577 tts: TokenStream::concat(tokens).into(),
583 fn from_tokens<I>(tokens: &mut iter::Peekable<I>) -> Option<MetaItemKind>
584 where I: Iterator<Item = TokenTree>,
586 let delimited = match tokens.peek().cloned() {
587 Some(TokenTree::Token(_, token::Eq)) => {
589 return if let Some(TokenTree::Token(span, token)) = tokens.next() {
590 LitKind::from_token(token)
591 .map(|lit| MetaItemKind::NameValue(Spanned { node: lit, span: span }))
596 Some(TokenTree::Delimited(_, ref delimited)) if delimited.delim == token::Paren => {
600 _ => return Some(MetaItemKind::Word),
603 let mut tokens = delimited.into_trees().peekable();
604 let mut result = Vec::new();
605 while let Some(..) = tokens.peek() {
606 let item = NestedMetaItemKind::from_tokens(&mut tokens)?;
607 result.push(respan(item.span(), item));
608 match tokens.next() {
609 None | Some(TokenTree::Token(_, Token::Comma)) => {}
613 Some(MetaItemKind::List(result))
617 impl NestedMetaItemKind {
618 fn span(&self) -> Span {
620 NestedMetaItemKind::MetaItem(ref item) => item.span,
621 NestedMetaItemKind::Literal(ref lit) => lit.span,
625 fn tokens(&self) -> TokenStream {
627 NestedMetaItemKind::MetaItem(ref item) => item.tokens(),
628 NestedMetaItemKind::Literal(ref lit) => lit.tokens(),
632 fn from_tokens<I>(tokens: &mut iter::Peekable<I>) -> Option<NestedMetaItemKind>
633 where I: Iterator<Item = TokenTree>,
635 if let Some(TokenTree::Token(span, token)) = tokens.peek().cloned() {
636 if let Some(node) = LitKind::from_token(token) {
638 return Some(NestedMetaItemKind::Literal(respan(span, node)));
642 MetaItem::from_tokens(tokens).map(NestedMetaItemKind::MetaItem)
647 fn tokens(&self) -> TokenStream {
648 TokenTree::Token(self.span, self.node.token()).into()
653 fn token(&self) -> Token {
657 LitKind::Str(string, ast::StrStyle::Cooked) => {
658 let escaped = string.as_str().escape_default();
659 Token::Literal(token::Lit::Str_(Symbol::intern(&escaped)), None)
661 LitKind::Str(string, ast::StrStyle::Raw(n)) => {
662 Token::Literal(token::Lit::StrRaw(string, n), None)
664 LitKind::ByteStr(ref bytes) => {
665 let string = bytes.iter().cloned().flat_map(ascii::escape_default)
666 .map(Into::<char>::into).collect::<String>();
667 Token::Literal(token::Lit::ByteStr(Symbol::intern(&string)), None)
669 LitKind::Byte(byte) => {
670 let string: String = ascii::escape_default(byte).map(Into::<char>::into).collect();
671 Token::Literal(token::Lit::Byte(Symbol::intern(&string)), None)
673 LitKind::Char(ch) => {
674 let string: String = ch.escape_default().map(Into::<char>::into).collect();
675 Token::Literal(token::Lit::Char(Symbol::intern(&string)), None)
677 LitKind::Int(n, ty) => {
678 let suffix = match ty {
679 ast::LitIntType::Unsigned(ty) => Some(Symbol::intern(ty.ty_to_string())),
680 ast::LitIntType::Signed(ty) => Some(Symbol::intern(ty.ty_to_string())),
681 ast::LitIntType::Unsuffixed => None,
683 Token::Literal(token::Lit::Integer(Symbol::intern(&n.to_string())), suffix)
685 LitKind::Float(symbol, ty) => {
686 Token::Literal(token::Lit::Float(symbol), Some(Symbol::intern(ty.ty_to_string())))
688 LitKind::FloatUnsuffixed(symbol) => Token::Literal(token::Lit::Float(symbol), None),
689 LitKind::Bool(value) => Token::Ident(Ident::with_empty_ctxt(Symbol::intern(if value {
697 fn from_token(token: Token) -> Option<LitKind> {
699 Token::Ident(ident, false) if ident.name == "true" => Some(LitKind::Bool(true)),
700 Token::Ident(ident, false) if ident.name == "false" => Some(LitKind::Bool(false)),
701 Token::Interpolated(ref nt) => match nt.0 {
702 token::NtExpr(ref v) | token::NtLiteral(ref v) => match v.node {
703 ExprKind::Lit(ref lit) => Some(lit.node.clone()),
708 Token::Literal(lit, suf) => {
709 let (suffix_illegal, result) = parse::lit_token(lit, suf, None);
710 if suffix_illegal && suf.is_some() {
720 pub trait HasAttrs: Sized {
721 fn attrs(&self) -> &[ast::Attribute];
722 fn map_attrs<F: FnOnce(Vec<ast::Attribute>) -> Vec<ast::Attribute>>(self, f: F) -> Self;
725 impl<T: HasAttrs> HasAttrs for Spanned<T> {
726 fn attrs(&self) -> &[ast::Attribute] { self.node.attrs() }
727 fn map_attrs<F: FnOnce(Vec<ast::Attribute>) -> Vec<ast::Attribute>>(self, f: F) -> Self {
728 respan(self.span, self.node.map_attrs(f))
732 impl HasAttrs for Vec<Attribute> {
733 fn attrs(&self) -> &[Attribute] {
736 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(self, f: F) -> Self {
741 impl HasAttrs for ThinVec<Attribute> {
742 fn attrs(&self) -> &[Attribute] {
745 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(self, f: F) -> Self {
746 f(self.into()).into()
750 impl<T: HasAttrs + 'static> HasAttrs for P<T> {
751 fn attrs(&self) -> &[Attribute] {
754 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(self, f: F) -> Self {
755 self.map(|t| t.map_attrs(f))
759 impl HasAttrs for StmtKind {
760 fn attrs(&self) -> &[Attribute] {
762 StmtKind::Local(ref local) => local.attrs(),
763 StmtKind::Item(..) => &[],
764 StmtKind::Expr(ref expr) | StmtKind::Semi(ref expr) => expr.attrs(),
765 StmtKind::Mac(ref mac) => {
766 let (_, _, ref attrs) = **mac;
772 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(self, f: F) -> Self {
774 StmtKind::Local(local) => StmtKind::Local(local.map_attrs(f)),
775 StmtKind::Item(..) => self,
776 StmtKind::Expr(expr) => StmtKind::Expr(expr.map_attrs(f)),
777 StmtKind::Semi(expr) => StmtKind::Semi(expr.map_attrs(f)),
778 StmtKind::Mac(mac) => StmtKind::Mac(mac.map(|(mac, style, attrs)| {
779 (mac, style, attrs.map_attrs(f))
785 impl HasAttrs for Stmt {
786 fn attrs(&self) -> &[ast::Attribute] { self.node.attrs() }
787 fn map_attrs<F: FnOnce(Vec<ast::Attribute>) -> Vec<ast::Attribute>>(self, f: F) -> Self {
788 Stmt { id: self.id, node: self.node.map_attrs(f), span: self.span }
792 impl HasAttrs for GenericParam {
793 fn attrs(&self) -> &[ast::Attribute] {
797 fn map_attrs<F: FnOnce(Vec<Attribute>) -> Vec<Attribute>>(mut self, f: F) -> Self {
798 self.attrs = self.attrs.map_attrs(f);
803 macro_rules! derive_has_attrs {
804 ($($ty:path),*) => { $(
805 impl HasAttrs for $ty {
806 fn attrs(&self) -> &[Attribute] {
810 fn map_attrs<F>(mut self, f: F) -> Self
811 where F: FnOnce(Vec<Attribute>) -> Vec<Attribute>,
813 self.attrs = self.attrs.map_attrs(f);
821 Item, Expr, Local, ast::ForeignItem, ast::StructField, ast::ImplItem, ast::TraitItem, ast::Arm,
822 ast::Field, ast::FieldPat, ast::Variant_