diff options
Diffstat (limited to 'src/librustc_ast/token.rs')
| -rw-r--r-- | src/librustc_ast/token.rs | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/src/librustc_ast/token.rs b/src/librustc_ast/token.rs index a5b9c2a95bb..89be3e6e212 100644 --- a/src/librustc_ast/token.rs +++ b/src/librustc_ast/token.rs @@ -182,6 +182,15 @@ fn ident_can_begin_type(name: Symbol, span: Span, is_raw: bool) -> bool { .contains(&name) } +/// A hack used to pass AST fragments to attribute and derive macros +/// as a single nonterminal token instead of a token stream. +/// FIXME: It needs to be removed, but there are some compatibility issues (see #73345). +#[derive(Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable_Generic)] +pub enum FlattenGroup { + Yes, + No, +} + #[derive(Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable_Generic)] pub enum TokenKind { /* Expression-operator symbols. */ @@ -236,7 +245,7 @@ pub enum TokenKind { /// treat regular and interpolated lifetime identifiers in the same way. Lifetime(Symbol), - Interpolated(Lrc<Nonterminal>), + Interpolated(Lrc<Nonterminal>, FlattenGroup), // Can be expanded into several tokens. /// A doc comment. @@ -343,7 +352,7 @@ impl Token { /// if they keep spans or perform edition checks. pub fn uninterpolated_span(&self) -> Span { match &self.kind { - Interpolated(nt) => nt.span(), + Interpolated(nt, _) => nt.span(), _ => self.span, } } @@ -382,7 +391,7 @@ impl Token { ModSep | // global path Lifetime(..) | // labeled loop Pound => true, // expression attributes - Interpolated(ref nt) => match **nt { + Interpolated(ref nt, _) => match **nt { NtLiteral(..) | NtExpr(..) | NtBlock(..) | @@ -408,7 +417,7 @@ impl Token { Lifetime(..) | // lifetime bound in trait object Lt | BinOp(Shl) | // associated path ModSep => true, // global path - Interpolated(ref nt) => match **nt { + Interpolated(ref nt, _) => match **nt { NtTy(..) | NtPath(..) => true, _ => false, }, @@ -420,7 +429,7 @@ impl Token { pub fn can_begin_const_arg(&self) -> bool { match self.kind { OpenDelim(Brace) => true, - Interpolated(ref nt) => match **nt { + Interpolated(ref nt, _) => match **nt { NtExpr(..) | NtBlock(..) | NtLiteral(..) => true, _ => false, }, @@ -455,7 +464,7 @@ impl Token { match self.uninterpolate().kind { Literal(..) | BinOp(Minus) => true, Ident(name, false) if name.is_bool_lit() => true, - Interpolated(ref nt) => match &**nt { + Interpolated(ref nt, _) => match &**nt { NtLiteral(_) => true, NtExpr(e) => match &e.kind { ast::ExprKind::Lit(_) => true, @@ -476,7 +485,7 @@ impl Token { // otherwise returns the original token. pub fn uninterpolate(&self) -> Cow<'_, Token> { match &self.kind { - Interpolated(nt) => match **nt { + Interpolated(nt, _) => match **nt { NtIdent(ident, is_raw) => { Cow::Owned(Token::new(Ident(ident.name, is_raw), ident.span)) } @@ -523,7 +532,7 @@ impl Token { /// Returns `true` if the token is an interpolated path. fn is_path(&self) -> bool { - if let Interpolated(ref nt) = self.kind { + if let Interpolated(ref nt, _) = self.kind { if let NtPath(..) = **nt { return true; } @@ -535,7 +544,7 @@ impl Token { /// That is, is this a pre-parsed expression dropped into the token stream /// (which happens while parsing the result of macro expansion)? pub fn is_whole_expr(&self) -> bool { - if let Interpolated(ref nt) = self.kind { + if let Interpolated(ref nt, _) = self.kind { if let NtExpr(_) | NtLiteral(_) | NtPath(_) | NtIdent(..) | NtBlock(_) = **nt { return true; } @@ -546,7 +555,7 @@ impl Token { // Is the token an interpolated block (`$b:block`)? pub fn is_whole_block(&self) -> bool { - if let Interpolated(ref nt) = self.kind { + if let Interpolated(ref nt, _) = self.kind { if let NtBlock(..) = **nt { return true; } @@ -724,7 +733,7 @@ impl Token { b == d && (a == c || a == kw::DollarCrate || c == kw::DollarCrate) } - (&Interpolated(_), &Interpolated(_)) => false, + (&Interpolated(..), &Interpolated(..)) => false, _ => panic!("forgot to add a token?"), } |