diff options
Diffstat (limited to 'compiler/rustc_ast/src/token.rs')
| -rw-r--r-- | compiler/rustc_ast/src/token.rs | 133 |
1 files changed, 16 insertions, 117 deletions
diff --git a/compiler/rustc_ast/src/token.rs b/compiler/rustc_ast/src/token.rs index d57a369eebf..055481f5d87 100644 --- a/compiler/rustc_ast/src/token.rs +++ b/compiler/rustc_ast/src/token.rs @@ -1,13 +1,10 @@ use std::borrow::Cow; use std::fmt; -use std::sync::Arc; pub use LitKind::*; -pub use Nonterminal::*; pub use NtExprKind::*; pub use NtPatKind::*; pub use TokenKind::*; -use rustc_data_structures::stable_hasher::{HashStable, StableHasher}; use rustc_macros::{Decodable, Encodable, HashStable_Generic}; use rustc_span::edition::Edition; use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span, kw, sym}; @@ -16,7 +13,6 @@ use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span, kw, sym}; use rustc_span::{Ident, Symbol}; use crate::ast; -use crate::ptr::P; use crate::util::case::Case; #[derive(Clone, Copy, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)] @@ -34,10 +30,6 @@ pub enum InvisibleOrigin { // Converted from `proc_macro::Delimiter` in // `proc_macro::Delimiter::to_internal`, i.e. returned by a proc macro. ProcMacro, - - // Converted from `TokenKind::Interpolated` in - // `TokenStream::flatten_token`. Treated similarly to `ProcMacro`. - FlattenToken, } impl PartialEq for InvisibleOrigin { @@ -134,9 +126,7 @@ impl Delimiter { match self { Delimiter::Parenthesis | Delimiter::Bracket | Delimiter::Brace => false, Delimiter::Invisible(InvisibleOrigin::MetaVar(_)) => false, - Delimiter::Invisible(InvisibleOrigin::FlattenToken | InvisibleOrigin::ProcMacro) => { - true - } + Delimiter::Invisible(InvisibleOrigin::ProcMacro) => true, } } @@ -337,9 +327,7 @@ impl From<IdentIsRaw> for bool { } } -// SAFETY: due to the `Clone` impl below, all fields of all variants other than -// `Interpolated` must impl `Copy`. -#[derive(PartialEq, Encodable, Decodable, Debug, HashStable_Generic)] +#[derive(Clone, Copy, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)] pub enum TokenKind { /* Expression-operator symbols. */ /// `=` @@ -468,21 +456,6 @@ pub enum TokenKind { /// the `lifetime` metavariable in the macro's RHS. NtLifetime(Ident, IdentIsRaw), - /// An embedded AST node, as produced by a macro. This only exists for - /// historical reasons. We'd like to get rid of it, for multiple reasons. - /// - It's conceptually very strange. Saying a token can contain an AST - /// node is like saying, in natural language, that a word can contain a - /// sentence. - /// - It requires special handling in a bunch of places in the parser. - /// - It prevents `Token` from implementing `Copy`. - /// It adds complexity and likely slows things down. Please don't add new - /// occurrences of this token kind! - /// - /// The span in the surrounding `Token` is that of the metavariable in the - /// macro's RHS. The span within the Nonterminal is that of the fragment - /// passed to the macro at the call site. - Interpolated(Arc<Nonterminal>), - /// A doc comment token. /// `Symbol` is the doc comment's data excluding its "quotes" (`///`, `/**`, etc) /// similarly to symbols in string literal tokens. @@ -492,20 +465,7 @@ pub enum TokenKind { Eof, } -impl Clone for TokenKind { - fn clone(&self) -> Self { - // `TokenKind` would impl `Copy` if it weren't for `Interpolated`. So - // for all other variants, this implementation of `clone` is just like - // a copy. This is faster than the `derive(Clone)` version which has a - // separate path for every variant. - match self { - Interpolated(nt) => Interpolated(Arc::clone(nt)), - _ => unsafe { std::ptr::read(self) }, - } - } -} - -#[derive(Clone, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)] +#[derive(Clone, Copy, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)] pub struct Token { pub kind: TokenKind, pub span: Span, @@ -600,7 +560,7 @@ impl Token { | FatArrow | Pound | Dollar | Question | SingleQuote => true, OpenDelim(..) | CloseDelim(..) | Literal(..) | DocComment(..) | Ident(..) - | NtIdent(..) | Lifetime(..) | NtLifetime(..) | Interpolated(..) | Eof => false, + | NtIdent(..) | Lifetime(..) | NtLifetime(..) | Eof => false, } } @@ -631,7 +591,6 @@ impl Token { PathSep | // global path Lifetime(..) | // labeled loop Pound => true, // expression attributes - Interpolated(ref nt) => matches!(&**nt, NtBlock(..)), OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar( MetaVarKind::Block | MetaVarKind::Expr { .. } | @@ -703,7 +662,6 @@ impl Token { match self.kind { OpenDelim(Delimiter::Brace) | Literal(..) | Minus => true, Ident(name, IdentIsRaw::No) if name.is_bool_lit() => true, - Interpolated(ref nt) => matches!(&**nt, NtBlock(..)), OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar( MetaVarKind::Expr { .. } | MetaVarKind::Block | MetaVarKind::Literal, ))) => true, @@ -831,31 +789,20 @@ impl Token { /// Is this a pre-parsed expression dropped into the token stream /// (which happens while parsing the result of macro expansion)? pub fn is_metavar_expr(&self) -> bool { - #[allow(irrefutable_let_patterns)] // FIXME: temporary - if let Interpolated(nt) = &self.kind - && let NtBlock(_) = &**nt - { - true - } else if matches!( + matches!( self.is_metavar_seq(), - Some(MetaVarKind::Expr { .. } | MetaVarKind::Literal | MetaVarKind::Path) - ) { - true - } else { - matches!(self.is_metavar_seq(), Some(MetaVarKind::Path)) - } + Some( + MetaVarKind::Expr { .. } + | MetaVarKind::Literal + | MetaVarKind::Path + | MetaVarKind::Block + ) + ) } - /// Is the token an interpolated block (`$b:block`)? - pub fn is_whole_block(&self) -> bool { - #[allow(irrefutable_let_patterns)] // FIXME: temporary - if let Interpolated(nt) = &self.kind - && let NtBlock(..) = &**nt - { - return true; - } - - false + /// Are we at a block from a metavar (`$b:block`)? + pub fn is_metavar_block(&self) -> bool { + matches!(self.is_metavar_seq(), Some(MetaVarKind::Block)) } /// Returns `true` if the token is either the `mut` or `const` keyword. @@ -1024,7 +971,7 @@ impl Token { | PercentEq | CaretEq | AndEq | OrEq | ShlEq | ShrEq | At | DotDotDot | DotDotEq | Comma | Semi | PathSep | RArrow | LArrow | FatArrow | Pound | Dollar | Question | OpenDelim(..) | CloseDelim(..) | Literal(..) | Ident(..) | NtIdent(..) - | Lifetime(..) | NtLifetime(..) | Interpolated(..) | DocComment(..) | Eof, + | Lifetime(..) | NtLifetime(..) | DocComment(..) | Eof, _, ) => { return None; @@ -1063,12 +1010,6 @@ pub enum NtExprKind { Expr2021 { inferred: bool }, } -#[derive(Clone, Encodable, Decodable)] -/// For interpolation during macro expansion. -pub enum Nonterminal { - NtBlock(P<ast::Block>), -} - #[derive(Debug, Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, HashStable_Generic)] pub enum NonterminalKind { Item, @@ -1152,47 +1093,6 @@ impl fmt::Display for NonterminalKind { } } -impl Nonterminal { - pub fn use_span(&self) -> Span { - match self { - NtBlock(block) => block.span, - } - } - - pub fn descr(&self) -> &'static str { - match self { - NtBlock(..) => "block", - } - } -} - -impl PartialEq for Nonterminal { - fn eq(&self, _rhs: &Self) -> bool { - // FIXME: Assume that all nonterminals are not equal, we can't compare them - // correctly based on data from AST. This will prevent them from matching each other - // in macros. The comparison will become possible only when each nonterminal has an - // attached token stream from which it was parsed. - false - } -} - -impl fmt::Debug for Nonterminal { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - match *self { - NtBlock(..) => f.pad("NtBlock(..)"), - } - } -} - -impl<CTX> HashStable<CTX> for Nonterminal -where - CTX: crate::HashStableContext, -{ - fn hash_stable(&self, _hcx: &mut CTX, _hasher: &mut StableHasher) { - panic!("interpolated tokens should not be present in the HIR") - } -} - // Some types are used a lot. Make sure they don't unintentionally get bigger. #[cfg(target_pointer_width = "64")] mod size_asserts { @@ -1202,7 +1102,6 @@ mod size_asserts { // tidy-alphabetical-start static_assert_size!(Lit, 12); static_assert_size!(LitKind, 2); - static_assert_size!(Nonterminal, 8); static_assert_size!(Token, 24); static_assert_size!(TokenKind, 16); // tidy-alphabetical-end |