mirror of
https://github.com/rust-lang/rust.git
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1564318482
`rustc_symbol` is the source of truth for keywords. rustdoc has its own implicit definition of keywords, via the `is_doc_keyword`. It (presumably) intends to include all keywords, but it omits `yeet`. rustfmt has its own explicit list of Rust keywords. It also (presumably) intends to include all keywords, but it omits `await`, `builtin`, `gen`, `macro_rules`, `raw`, `reuse`, `safe`, and `yeet`. Also, it does linear searches through this list, which is inefficient. This commit fixes all of the above problems by introducing a new predicate `is_any_keyword` in rustc and using it in rustdoc and rustfmt. It documents that it's not the right predicate in most cases.
1241 lines
43 KiB
Rust
1241 lines
43 KiB
Rust
use std::borrow::Cow;
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use std::fmt;
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pub use BinOpToken::*;
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pub use LitKind::*;
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pub use Nonterminal::*;
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pub use NtExprKind::*;
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pub use NtPatKind::*;
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pub use TokenKind::*;
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use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
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use rustc_data_structures::sync::Lrc;
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use rustc_macros::{Decodable, Encodable, HashStable_Generic};
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use rustc_span::edition::Edition;
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use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span, kw, sym};
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#[allow(clippy::useless_attribute)] // FIXME: following use of `hidden_glob_reexports` incorrectly triggers `useless_attribute` lint.
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#[allow(hidden_glob_reexports)]
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use rustc_span::{Ident, Symbol};
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use crate::ast;
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use crate::ptr::P;
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use crate::util::case::Case;
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#[derive(Clone, Copy, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)]
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pub enum CommentKind {
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Line,
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Block,
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}
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#[derive(Clone, PartialEq, Encodable, Decodable, Hash, Debug, Copy)]
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#[derive(HashStable_Generic)]
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pub enum BinOpToken {
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Plus,
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Minus,
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Star,
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Slash,
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Percent,
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Caret,
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And,
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Or,
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Shl,
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Shr,
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}
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// This type must not implement `Hash` due to the unusual `PartialEq` impl below.
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#[derive(Copy, Clone, Debug, Encodable, Decodable, HashStable_Generic)]
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pub enum InvisibleOrigin {
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// From the expansion of a metavariable in a declarative macro.
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MetaVar(MetaVarKind),
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// Converted from `proc_macro::Delimiter` in
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// `proc_macro::Delimiter::to_internal`, i.e. returned by a proc macro.
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ProcMacro,
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// Converted from `TokenKind::Interpolated` in
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// `TokenStream::flatten_token`. Treated similarly to `ProcMacro`.
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FlattenToken,
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}
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impl PartialEq for InvisibleOrigin {
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#[inline]
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fn eq(&self, _other: &InvisibleOrigin) -> bool {
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// When we had AST-based nonterminals we couldn't compare them, and the
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// old `Nonterminal` type had an `eq` that always returned false,
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// resulting in this restriction:
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// https://doc.rust-lang.org/nightly/reference/macros-by-example.html#forwarding-a-matched-fragment
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// This `eq` emulates that behaviour. We could consider lifting this
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// restriction now but there are still cases involving invisible
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// delimiters that make it harder than it first appears.
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false
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}
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}
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/// Annoyingly similar to `NonterminalKind`, but the slight differences are important.
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#[derive(Debug, Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, HashStable_Generic)]
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pub enum MetaVarKind {
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Item,
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Block,
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Stmt,
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Pat(NtPatKind),
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Expr {
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kind: NtExprKind,
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// This field is needed for `Token::can_begin_literal_maybe_minus`.
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can_begin_literal_maybe_minus: bool,
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// This field is needed for `Token::can_begin_string_literal`.
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can_begin_string_literal: bool,
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},
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Ty,
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Ident,
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Lifetime,
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Literal,
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Meta,
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Path,
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Vis,
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TT,
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}
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impl fmt::Display for MetaVarKind {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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let sym = match self {
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MetaVarKind::Item => sym::item,
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MetaVarKind::Block => sym::block,
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MetaVarKind::Stmt => sym::stmt,
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MetaVarKind::Pat(PatParam { inferred: true } | PatWithOr) => sym::pat,
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MetaVarKind::Pat(PatParam { inferred: false }) => sym::pat_param,
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MetaVarKind::Expr { kind: Expr2021 { inferred: true } | Expr, .. } => sym::expr,
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MetaVarKind::Expr { kind: Expr2021 { inferred: false }, .. } => sym::expr_2021,
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MetaVarKind::Ty => sym::ty,
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MetaVarKind::Ident => sym::ident,
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MetaVarKind::Lifetime => sym::lifetime,
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MetaVarKind::Literal => sym::literal,
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MetaVarKind::Meta => sym::meta,
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MetaVarKind::Path => sym::path,
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MetaVarKind::Vis => sym::vis,
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MetaVarKind::TT => sym::tt,
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};
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write!(f, "{sym}")
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}
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}
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/// Describes how a sequence of token trees is delimited.
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/// Cannot use `proc_macro::Delimiter` directly because this
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/// structure should implement some additional traits.
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#[derive(Copy, Clone, Debug, PartialEq, Encodable, Decodable, HashStable_Generic)]
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pub enum Delimiter {
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/// `( ... )`
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Parenthesis,
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/// `{ ... }`
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Brace,
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/// `[ ... ]`
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Bracket,
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/// `∅ ... ∅`
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/// An invisible delimiter, that may, for example, appear around tokens coming from a
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/// "macro variable" `$var`. It is important to preserve operator priorities in cases like
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/// `$var * 3` where `$var` is `1 + 2`.
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/// Invisible delimiters might not survive roundtrip of a token stream through a string.
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Invisible(InvisibleOrigin),
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}
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impl Delimiter {
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// Should the parser skip these delimiters? Only happens for certain kinds
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// of invisible delimiters. Ideally this function will eventually disappear
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// and no invisible delimiters will be skipped.
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#[inline]
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pub fn skip(&self) -> bool {
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match self {
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Delimiter::Parenthesis | Delimiter::Bracket | Delimiter::Brace => false,
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Delimiter::Invisible(InvisibleOrigin::MetaVar(_)) => false,
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Delimiter::Invisible(InvisibleOrigin::FlattenToken | InvisibleOrigin::ProcMacro) => {
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true
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}
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}
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}
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// This exists because `InvisibleOrigin`s should be compared. It is only used for assertions.
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pub fn eq_ignoring_invisible_origin(&self, other: &Delimiter) -> bool {
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match (self, other) {
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(Delimiter::Parenthesis, Delimiter::Parenthesis) => true,
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(Delimiter::Brace, Delimiter::Brace) => true,
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(Delimiter::Bracket, Delimiter::Bracket) => true,
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(Delimiter::Invisible(_), Delimiter::Invisible(_)) => true,
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_ => false,
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}
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}
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}
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// Note that the suffix is *not* considered when deciding the `LitKind` in this
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// type. This means that float literals like `1f32` are classified by this type
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// as `Int`. Only upon conversion to `ast::LitKind` will such a literal be
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// given the `Float` kind.
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#[derive(Clone, Copy, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)]
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pub enum LitKind {
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Bool, // AST only, must never appear in a `Token`
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Byte,
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Char,
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Integer, // e.g. `1`, `1u8`, `1f32`
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Float, // e.g. `1.`, `1.0`, `1e3f32`
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Str,
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StrRaw(u8), // raw string delimited by `n` hash symbols
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ByteStr,
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ByteStrRaw(u8), // raw byte string delimited by `n` hash symbols
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CStr,
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CStrRaw(u8),
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Err(ErrorGuaranteed),
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}
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/// A literal token.
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#[derive(Clone, Copy, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)]
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pub struct Lit {
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pub kind: LitKind,
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pub symbol: Symbol,
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pub suffix: Option<Symbol>,
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}
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impl Lit {
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pub fn new(kind: LitKind, symbol: Symbol, suffix: Option<Symbol>) -> Lit {
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Lit { kind, symbol, suffix }
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}
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/// Returns `true` if this is semantically a float literal. This includes
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/// ones like `1f32` that have an `Integer` kind but a float suffix.
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pub fn is_semantic_float(&self) -> bool {
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match self.kind {
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LitKind::Float => true,
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LitKind::Integer => match self.suffix {
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Some(sym) => sym == sym::f32 || sym == sym::f64,
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None => false,
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},
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_ => false,
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}
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}
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/// Keep this in sync with `Token::can_begin_literal_maybe_minus` excluding unary negation.
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pub fn from_token(token: &Token) -> Option<Lit> {
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match token.uninterpolate().kind {
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Ident(name, IdentIsRaw::No) if name.is_bool_lit() => Some(Lit::new(Bool, name, None)),
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Literal(token_lit) => Some(token_lit),
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Interpolated(ref nt)
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if let NtExpr(expr) | NtLiteral(expr) = &**nt
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&& let ast::ExprKind::Lit(token_lit) = expr.kind =>
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{
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Some(token_lit)
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}
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_ => None,
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}
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}
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}
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impl fmt::Display for Lit {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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let Lit { kind, symbol, suffix } = *self;
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match kind {
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Byte => write!(f, "b'{symbol}'")?,
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Char => write!(f, "'{symbol}'")?,
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Str => write!(f, "\"{symbol}\"")?,
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StrRaw(n) => write!(
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f,
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"r{delim}\"{string}\"{delim}",
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delim = "#".repeat(n as usize),
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string = symbol
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)?,
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ByteStr => write!(f, "b\"{symbol}\"")?,
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ByteStrRaw(n) => write!(
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f,
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"br{delim}\"{string}\"{delim}",
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delim = "#".repeat(n as usize),
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string = symbol
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)?,
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CStr => write!(f, "c\"{symbol}\"")?,
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CStrRaw(n) => {
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write!(f, "cr{delim}\"{symbol}\"{delim}", delim = "#".repeat(n as usize))?
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}
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Integer | Float | Bool | Err(_) => write!(f, "{symbol}")?,
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}
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if let Some(suffix) = suffix {
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write!(f, "{suffix}")?;
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}
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Ok(())
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}
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}
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impl LitKind {
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/// An English article for the literal token kind.
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pub fn article(self) -> &'static str {
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match self {
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Integer | Err(_) => "an",
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_ => "a",
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}
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}
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pub fn descr(self) -> &'static str {
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match self {
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Bool => "boolean",
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Byte => "byte",
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Char => "char",
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Integer => "integer",
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Float => "float",
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Str | StrRaw(..) => "string",
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ByteStr | ByteStrRaw(..) => "byte string",
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CStr | CStrRaw(..) => "C string",
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Err(_) => "error",
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}
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}
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pub(crate) fn may_have_suffix(self) -> bool {
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matches!(self, Integer | Float | Err(_))
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}
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}
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pub fn ident_can_begin_expr(name: Symbol, span: Span, is_raw: IdentIsRaw) -> bool {
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let ident_token = Token::new(Ident(name, is_raw), span);
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!ident_token.is_reserved_ident()
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|| ident_token.is_path_segment_keyword()
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|| [
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kw::Async,
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kw::Do,
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kw::Box,
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kw::Break,
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kw::Const,
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kw::Continue,
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kw::False,
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kw::For,
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kw::Gen,
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kw::If,
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kw::Let,
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kw::Loop,
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kw::Match,
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kw::Move,
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kw::Return,
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kw::True,
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kw::Try,
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kw::Unsafe,
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kw::While,
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kw::Yield,
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kw::Safe,
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kw::Static,
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]
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.contains(&name)
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}
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fn ident_can_begin_type(name: Symbol, span: Span, is_raw: IdentIsRaw) -> bool {
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let ident_token = Token::new(Ident(name, is_raw), span);
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!ident_token.is_reserved_ident()
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|| ident_token.is_path_segment_keyword()
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|| [kw::Underscore, kw::For, kw::Impl, kw::Fn, kw::Unsafe, kw::Extern, kw::Typeof, kw::Dyn]
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.contains(&name)
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}
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#[derive(PartialEq, Encodable, Decodable, Debug, Copy, Clone, HashStable_Generic)]
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pub enum IdentIsRaw {
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No,
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Yes,
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}
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impl From<bool> for IdentIsRaw {
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fn from(b: bool) -> Self {
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if b { Self::Yes } else { Self::No }
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}
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}
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impl From<IdentIsRaw> for bool {
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fn from(is_raw: IdentIsRaw) -> bool {
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matches!(is_raw, IdentIsRaw::Yes)
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}
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}
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// SAFETY: due to the `Clone` impl below, all fields of all variants other than
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// `Interpolated` must impl `Copy`.
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#[derive(PartialEq, Encodable, Decodable, Debug, HashStable_Generic)]
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pub enum TokenKind {
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/* Expression-operator symbols. */
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/// `=`
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Eq,
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/// `<`
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Lt,
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/// `<=`
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Le,
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/// `==`
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EqEq,
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/// `!=`
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Ne,
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/// `>=`
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Ge,
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/// `>`
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Gt,
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/// `&&`
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AndAnd,
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/// `||`
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OrOr,
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/// `!`
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Not,
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/// `~`
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Tilde,
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BinOp(BinOpToken),
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BinOpEq(BinOpToken),
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/* Structural symbols */
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/// `@`
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At,
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/// `.`
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Dot,
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/// `..`
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DotDot,
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/// `...`
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DotDotDot,
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/// `..=`
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DotDotEq,
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/// `,`
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Comma,
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/// `;`
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Semi,
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/// `:`
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Colon,
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/// `::`
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PathSep,
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/// `->`
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RArrow,
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/// `<-`
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LArrow,
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/// `=>`
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FatArrow,
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/// `#`
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Pound,
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/// `$`
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Dollar,
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/// `?`
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Question,
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/// Used by proc macros for representing lifetimes, not generated by lexer right now.
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SingleQuote,
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/// An opening delimiter (e.g., `{`).
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OpenDelim(Delimiter),
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/// A closing delimiter (e.g., `}`).
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CloseDelim(Delimiter),
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/* Literals */
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Literal(Lit),
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/// Identifier token.
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/// Do not forget about `NtIdent` when you want to match on identifiers.
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/// It's recommended to use `Token::(ident,uninterpolate,uninterpolated_span)` to
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/// treat regular and interpolated identifiers in the same way.
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Ident(Symbol, IdentIsRaw),
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/// This identifier (and its span) is the identifier passed to the
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/// declarative macro. The span in the surrounding `Token` is the span of
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/// the `ident` metavariable in the macro's RHS.
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NtIdent(Ident, IdentIsRaw),
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/// Lifetime identifier token.
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/// Do not forget about `NtLifetime` when you want to match on lifetime identifiers.
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/// It's recommended to use `Token::(lifetime,uninterpolate,uninterpolated_span)` to
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/// treat regular and interpolated lifetime identifiers in the same way.
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Lifetime(Symbol, IdentIsRaw),
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/// This identifier (and its span) is the lifetime passed to the
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/// declarative macro. The span in the surrounding `Token` is the span of
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/// the `lifetime` metavariable in the macro's RHS.
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NtLifetime(Ident, IdentIsRaw),
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/// An embedded AST node, as produced by a macro. This only exists for
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/// historical reasons. We'd like to get rid of it, for multiple reasons.
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/// - It's conceptually very strange. Saying a token can contain an AST
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/// node is like saying, in natural language, that a word can contain a
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/// sentence.
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/// - It requires special handling in a bunch of places in the parser.
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/// - It prevents `Token` from implementing `Copy`.
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/// It adds complexity and likely slows things down. Please don't add new
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/// occurrences of this token kind!
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///
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/// The span in the surrounding `Token` is that of the metavariable in the
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/// macro's RHS. The span within the Nonterminal is that of the fragment
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/// passed to the macro at the call site.
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Interpolated(Lrc<Nonterminal>),
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|
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/// A doc comment token.
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/// `Symbol` is the doc comment's data excluding its "quotes" (`///`, `/**`, etc)
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|
/// similarly to symbols in string literal tokens.
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|
DocComment(CommentKind, ast::AttrStyle, Symbol),
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|
|
/// End Of File
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|
Eof,
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|
}
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|
|
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impl Clone for TokenKind {
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|
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
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|
// a copy. This is faster than the `derive(Clone)` version which has a
|
|
// separate path for every variant.
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|
match self {
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|
Interpolated(nt) => Interpolated(Lrc::clone(nt)),
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|
_ => unsafe { std::ptr::read(self) },
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}
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}
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}
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|
|
#[derive(Clone, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)]
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|
pub struct Token {
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|
pub kind: TokenKind,
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|
pub span: Span,
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}
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|
|
|
impl TokenKind {
|
|
pub fn lit(kind: LitKind, symbol: Symbol, suffix: Option<Symbol>) -> TokenKind {
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Literal(Lit::new(kind, symbol, suffix))
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}
|
|
|
|
/// An approximation to proc-macro-style single-character operators used by
|
|
/// rustc parser. If the operator token can be broken into two tokens, the
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|
/// first of which has `n` (1 or 2) chars, then this function performs that
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|
/// operation, otherwise it returns `None`.
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|
pub fn break_two_token_op(&self, n: u32) -> Option<(TokenKind, TokenKind)> {
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|
assert!(n == 1 || n == 2);
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|
Some(match (self, n) {
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|
(Le, 1) => (Lt, Eq),
|
|
(EqEq, 1) => (Eq, Eq),
|
|
(Ne, 1) => (Not, Eq),
|
|
(Ge, 1) => (Gt, Eq),
|
|
(AndAnd, 1) => (BinOp(And), BinOp(And)),
|
|
(OrOr, 1) => (BinOp(Or), BinOp(Or)),
|
|
(BinOp(Shl), 1) => (Lt, Lt),
|
|
(BinOp(Shr), 1) => (Gt, Gt),
|
|
(BinOpEq(Plus), 1) => (BinOp(Plus), Eq),
|
|
(BinOpEq(Minus), 1) => (BinOp(Minus), Eq),
|
|
(BinOpEq(Star), 1) => (BinOp(Star), Eq),
|
|
(BinOpEq(Slash), 1) => (BinOp(Slash), Eq),
|
|
(BinOpEq(Percent), 1) => (BinOp(Percent), Eq),
|
|
(BinOpEq(Caret), 1) => (BinOp(Caret), Eq),
|
|
(BinOpEq(And), 1) => (BinOp(And), Eq),
|
|
(BinOpEq(Or), 1) => (BinOp(Or), Eq),
|
|
(BinOpEq(Shl), 1) => (Lt, Le), // `<` + `<=`
|
|
(BinOpEq(Shl), 2) => (BinOp(Shl), Eq), // `<<` + `=`
|
|
(BinOpEq(Shr), 1) => (Gt, Ge), // `>` + `>=`
|
|
(BinOpEq(Shr), 2) => (BinOp(Shr), Eq), // `>>` + `=`
|
|
(DotDot, 1) => (Dot, Dot),
|
|
(DotDotDot, 1) => (Dot, DotDot), // `.` + `..`
|
|
(DotDotDot, 2) => (DotDot, Dot), // `..` + `.`
|
|
(DotDotEq, 2) => (DotDot, Eq),
|
|
(PathSep, 1) => (Colon, Colon),
|
|
(RArrow, 1) => (BinOp(Minus), Gt),
|
|
(LArrow, 1) => (Lt, BinOp(Minus)),
|
|
(FatArrow, 1) => (Eq, Gt),
|
|
_ => return None,
|
|
})
|
|
}
|
|
|
|
/// Returns tokens that are likely to be typed accidentally instead of the current token.
|
|
/// Enables better error recovery when the wrong token is found.
|
|
pub fn similar_tokens(&self) -> Option<Vec<TokenKind>> {
|
|
match *self {
|
|
Comma => Some(vec![Dot, Lt, Semi]),
|
|
Semi => Some(vec![Colon, Comma]),
|
|
Colon => Some(vec![Semi]),
|
|
FatArrow => Some(vec![Eq, RArrow, Ge, Gt]),
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
pub fn should_end_const_arg(&self) -> bool {
|
|
matches!(self, Gt | Ge | BinOp(Shr) | BinOpEq(Shr))
|
|
}
|
|
}
|
|
|
|
impl Token {
|
|
pub fn new(kind: TokenKind, span: Span) -> Self {
|
|
Token { kind, span }
|
|
}
|
|
|
|
/// Some token that will be thrown away later.
|
|
pub fn dummy() -> Self {
|
|
Token::new(TokenKind::Question, DUMMY_SP)
|
|
}
|
|
|
|
/// Recovers a `Token` from an `Ident`. This creates a raw identifier if necessary.
|
|
pub fn from_ast_ident(ident: Ident) -> Self {
|
|
Token::new(Ident(ident.name, ident.is_raw_guess().into()), ident.span)
|
|
}
|
|
|
|
/// For interpolated tokens, returns a span of the fragment to which the interpolated
|
|
/// token refers. For all other tokens this is just a regular span.
|
|
/// It is particularly important to use this for identifiers and lifetimes
|
|
/// for which spans affect name resolution and edition checks.
|
|
/// Note that keywords are also identifiers, so they should use this
|
|
/// if they keep spans or perform edition checks.
|
|
pub fn uninterpolated_span(&self) -> Span {
|
|
match self.kind {
|
|
NtIdent(ident, _) | NtLifetime(ident, _) => ident.span,
|
|
Interpolated(ref nt) => nt.use_span(),
|
|
_ => self.span,
|
|
}
|
|
}
|
|
|
|
pub fn is_range_separator(&self) -> bool {
|
|
[DotDot, DotDotDot, DotDotEq].contains(&self.kind)
|
|
}
|
|
|
|
pub fn is_punct(&self) -> bool {
|
|
match self.kind {
|
|
Eq | Lt | Le | EqEq | Ne | Ge | Gt | AndAnd | OrOr | Not | Tilde | BinOp(_)
|
|
| BinOpEq(_) | At | Dot | DotDot | DotDotDot | DotDotEq | Comma | Semi | Colon
|
|
| PathSep | RArrow | LArrow | FatArrow | Pound | Dollar | Question | SingleQuote => {
|
|
true
|
|
}
|
|
|
|
OpenDelim(..) | CloseDelim(..) | Literal(..) | DocComment(..) | Ident(..)
|
|
| NtIdent(..) | Lifetime(..) | NtLifetime(..) | Interpolated(..) | Eof => false,
|
|
}
|
|
}
|
|
|
|
pub fn is_like_plus(&self) -> bool {
|
|
matches!(self.kind, BinOp(Plus) | BinOpEq(Plus))
|
|
}
|
|
|
|
/// Returns `true` if the token can appear at the start of an expression.
|
|
///
|
|
/// **NB**: Take care when modifying this function, since it will change
|
|
/// the stable set of tokens that are allowed to match an expr nonterminal.
|
|
pub fn can_begin_expr(&self) -> bool {
|
|
use Delimiter::*;
|
|
match self.uninterpolate().kind {
|
|
Ident(name, is_raw) =>
|
|
ident_can_begin_expr(name, self.span, is_raw), // value name or keyword
|
|
OpenDelim(Parenthesis | Brace | Bracket) | // tuple, array or block
|
|
Literal(..) | // literal
|
|
Not | // operator not
|
|
BinOp(Minus) | // unary minus
|
|
BinOp(Star) | // dereference
|
|
BinOp(Or) | OrOr | // closure
|
|
BinOp(And) | // reference
|
|
AndAnd | // double reference
|
|
// DotDotDot is no longer supported, but we need some way to display the error
|
|
DotDot | DotDotDot | DotDotEq | // range notation
|
|
Lt | BinOp(Shl) | // associated path
|
|
PathSep | // global path
|
|
Lifetime(..) | // labeled loop
|
|
Pound => true, // expression attributes
|
|
Interpolated(ref nt) =>
|
|
matches!(&**nt,
|
|
NtBlock(..) |
|
|
NtExpr(..) |
|
|
NtLiteral(..) |
|
|
NtPath(..)
|
|
),
|
|
OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(
|
|
MetaVarKind::Block |
|
|
MetaVarKind::Expr { .. } |
|
|
MetaVarKind::Literal |
|
|
MetaVarKind::Path
|
|
))) => true,
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
/// Returns `true` if the token can appear at the start of a pattern.
|
|
///
|
|
/// Shamelessly borrowed from `can_begin_expr`, only used for diagnostics right now.
|
|
pub fn can_begin_pattern(&self, pat_kind: NtPatKind) -> bool {
|
|
match &self.uninterpolate().kind {
|
|
// box, ref, mut, and other identifiers (can stricten)
|
|
Ident(..) | NtIdent(..) |
|
|
OpenDelim(Delimiter::Parenthesis) | // tuple pattern
|
|
OpenDelim(Delimiter::Bracket) | // slice pattern
|
|
BinOp(And) | // reference
|
|
BinOp(Minus) | // negative literal
|
|
AndAnd | // double reference
|
|
Literal(_) | // literal
|
|
DotDot | // range pattern (future compat)
|
|
DotDotDot | // range pattern (future compat)
|
|
PathSep | // path
|
|
Lt | // path (UFCS constant)
|
|
BinOp(Shl) => true, // path (double UFCS)
|
|
// leading vert `|` or-pattern
|
|
BinOp(Or) => matches!(pat_kind, PatWithOr),
|
|
Interpolated(nt) =>
|
|
matches!(&**nt,
|
|
| NtExpr(..)
|
|
| NtLiteral(..)
|
|
| NtMeta(..)
|
|
| NtPat(..)
|
|
| NtPath(..)
|
|
| NtTy(..)
|
|
),
|
|
OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(
|
|
MetaVarKind::Expr { .. } |
|
|
MetaVarKind::Literal |
|
|
MetaVarKind::Meta |
|
|
MetaVarKind::Pat(_) |
|
|
MetaVarKind::Path |
|
|
MetaVarKind::Ty
|
|
))) => true,
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
/// Returns `true` if the token can appear at the start of a type.
|
|
pub fn can_begin_type(&self) -> bool {
|
|
match self.uninterpolate().kind {
|
|
Ident(name, is_raw) =>
|
|
ident_can_begin_type(name, self.span, is_raw), // type name or keyword
|
|
OpenDelim(Delimiter::Parenthesis) | // tuple
|
|
OpenDelim(Delimiter::Bracket) | // array
|
|
Not | // never
|
|
BinOp(Star) | // raw pointer
|
|
BinOp(And) | // reference
|
|
AndAnd | // double reference
|
|
Question | // maybe bound in trait object
|
|
Lifetime(..) | // lifetime bound in trait object
|
|
Lt | BinOp(Shl) | // associated path
|
|
PathSep => true, // global path
|
|
Interpolated(ref nt) => matches!(&**nt, NtTy(..) | NtPath(..)),
|
|
OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(
|
|
MetaVarKind::Ty |
|
|
MetaVarKind::Path
|
|
))) => true,
|
|
// For anonymous structs or unions, which only appear in specific positions
|
|
// (type of struct fields or union fields), we don't consider them as regular types
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
/// Returns `true` if the token can appear at the start of a const param.
|
|
pub fn can_begin_const_arg(&self) -> bool {
|
|
match self.kind {
|
|
OpenDelim(Delimiter::Brace) | Literal(..) | BinOp(Minus) => true,
|
|
Ident(name, IdentIsRaw::No) if name.is_bool_lit() => true,
|
|
Interpolated(ref nt) => matches!(&**nt, NtExpr(..) | NtBlock(..) | NtLiteral(..)),
|
|
OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(
|
|
MetaVarKind::Expr { .. } | MetaVarKind::Block | MetaVarKind::Literal,
|
|
))) => true,
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
/// Returns `true` if the token can appear at the start of an item.
|
|
pub fn can_begin_item(&self) -> bool {
|
|
match self.kind {
|
|
Ident(name, _) => [
|
|
kw::Fn,
|
|
kw::Use,
|
|
kw::Struct,
|
|
kw::Enum,
|
|
kw::Pub,
|
|
kw::Trait,
|
|
kw::Extern,
|
|
kw::Impl,
|
|
kw::Unsafe,
|
|
kw::Const,
|
|
kw::Safe,
|
|
kw::Static,
|
|
kw::Union,
|
|
kw::Macro,
|
|
kw::Mod,
|
|
kw::Type,
|
|
]
|
|
.contains(&name),
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
/// Returns `true` if the token is any literal.
|
|
pub fn is_lit(&self) -> bool {
|
|
matches!(self.kind, Literal(..))
|
|
}
|
|
|
|
/// Returns `true` if the token is any literal, a minus (which can prefix a literal,
|
|
/// for example a '-42', or one of the boolean idents).
|
|
///
|
|
/// In other words, would this token be a valid start of `parse_literal_maybe_minus`?
|
|
///
|
|
/// Keep this in sync with and `Lit::from_token`, excluding unary negation.
|
|
pub fn can_begin_literal_maybe_minus(&self) -> bool {
|
|
match self.uninterpolate().kind {
|
|
Literal(..) | BinOp(Minus) => true,
|
|
Ident(name, IdentIsRaw::No) if name.is_bool_lit() => true,
|
|
Interpolated(ref nt) => match &**nt {
|
|
NtLiteral(_) => true,
|
|
NtExpr(e) => match &e.kind {
|
|
ast::ExprKind::Lit(_) => true,
|
|
ast::ExprKind::Unary(ast::UnOp::Neg, e) => {
|
|
matches!(&e.kind, ast::ExprKind::Lit(_))
|
|
}
|
|
_ => false,
|
|
},
|
|
_ => false,
|
|
},
|
|
OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(mv_kind))) => match mv_kind {
|
|
MetaVarKind::Literal => true,
|
|
MetaVarKind::Expr { can_begin_literal_maybe_minus, .. } => {
|
|
can_begin_literal_maybe_minus
|
|
}
|
|
_ => false,
|
|
},
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
pub fn can_begin_string_literal(&self) -> bool {
|
|
match self.uninterpolate().kind {
|
|
Literal(..) => true,
|
|
Interpolated(ref nt) => match &**nt {
|
|
NtLiteral(_) => true,
|
|
NtExpr(e) => match &e.kind {
|
|
ast::ExprKind::Lit(_) => true,
|
|
_ => false,
|
|
},
|
|
_ => false,
|
|
},
|
|
OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(mv_kind))) => match mv_kind {
|
|
MetaVarKind::Literal => true,
|
|
MetaVarKind::Expr { can_begin_string_literal, .. } => can_begin_string_literal,
|
|
_ => false,
|
|
},
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
/// A convenience function for matching on identifiers during parsing.
|
|
/// Turns interpolated identifier (`$i: ident`) or lifetime (`$l: lifetime`) token
|
|
/// into the regular identifier or lifetime token it refers to,
|
|
/// otherwise returns the original token.
|
|
pub fn uninterpolate(&self) -> Cow<'_, Token> {
|
|
match self.kind {
|
|
NtIdent(ident, is_raw) => Cow::Owned(Token::new(Ident(ident.name, is_raw), ident.span)),
|
|
NtLifetime(ident, is_raw) => {
|
|
Cow::Owned(Token::new(Lifetime(ident.name, is_raw), ident.span))
|
|
}
|
|
_ => Cow::Borrowed(self),
|
|
}
|
|
}
|
|
|
|
/// Returns an identifier if this token is an identifier.
|
|
#[inline]
|
|
pub fn ident(&self) -> Option<(Ident, IdentIsRaw)> {
|
|
// We avoid using `Token::uninterpolate` here because it's slow.
|
|
match self.kind {
|
|
Ident(name, is_raw) => Some((Ident::new(name, self.span), is_raw)),
|
|
NtIdent(ident, is_raw) => Some((ident, is_raw)),
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
/// Returns a lifetime identifier if this token is a lifetime.
|
|
#[inline]
|
|
pub fn lifetime(&self) -> Option<(Ident, IdentIsRaw)> {
|
|
// We avoid using `Token::uninterpolate` here because it's slow.
|
|
match self.kind {
|
|
Lifetime(name, is_raw) => Some((Ident::new(name, self.span), is_raw)),
|
|
NtLifetime(ident, is_raw) => Some((ident, is_raw)),
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
/// Returns `true` if the token is an identifier.
|
|
pub fn is_ident(&self) -> bool {
|
|
self.ident().is_some()
|
|
}
|
|
|
|
/// Returns `true` if the token is a lifetime.
|
|
pub fn is_lifetime(&self) -> bool {
|
|
self.lifetime().is_some()
|
|
}
|
|
|
|
/// Returns `true` if the token is an identifier whose name is the given
|
|
/// string slice.
|
|
pub fn is_ident_named(&self, name: Symbol) -> bool {
|
|
self.ident().is_some_and(|(ident, _)| ident.name == name)
|
|
}
|
|
|
|
/// Returns `true` if the token is an interpolated path.
|
|
fn is_whole_path(&self) -> bool {
|
|
if let Interpolated(nt) = &self.kind
|
|
&& let NtPath(..) = &**nt
|
|
{
|
|
return true;
|
|
}
|
|
|
|
false
|
|
}
|
|
|
|
/// 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(nt) = &self.kind
|
|
&& let NtExpr(_) | NtLiteral(_) | NtPath(_) | NtBlock(_) = &**nt
|
|
{
|
|
return true;
|
|
}
|
|
|
|
false
|
|
}
|
|
|
|
/// Is the token an interpolated block (`$b:block`)?
|
|
pub fn is_whole_block(&self) -> bool {
|
|
if let Interpolated(nt) = &self.kind
|
|
&& let NtBlock(..) = &**nt
|
|
{
|
|
return true;
|
|
}
|
|
|
|
false
|
|
}
|
|
|
|
/// Returns `true` if the token is either the `mut` or `const` keyword.
|
|
pub fn is_mutability(&self) -> bool {
|
|
self.is_keyword(kw::Mut) || self.is_keyword(kw::Const)
|
|
}
|
|
|
|
pub fn is_qpath_start(&self) -> bool {
|
|
self == &Lt || self == &BinOp(Shl)
|
|
}
|
|
|
|
pub fn is_path_start(&self) -> bool {
|
|
self == &PathSep
|
|
|| self.is_qpath_start()
|
|
|| self.is_whole_path()
|
|
|| self.is_path_segment_keyword()
|
|
|| self.is_ident() && !self.is_reserved_ident()
|
|
}
|
|
|
|
/// Returns `true` if the token is a given keyword, `kw`.
|
|
pub fn is_keyword(&self, kw: Symbol) -> bool {
|
|
self.is_non_raw_ident_where(|id| id.name == kw)
|
|
}
|
|
|
|
/// Returns `true` if the token is a given keyword, `kw` or if `case` is `Insensitive` and this
|
|
/// token is an identifier equal to `kw` ignoring the case.
|
|
pub fn is_keyword_case(&self, kw: Symbol, case: Case) -> bool {
|
|
self.is_keyword(kw)
|
|
|| (case == Case::Insensitive
|
|
&& self.is_non_raw_ident_where(|id| {
|
|
id.name.as_str().to_lowercase() == kw.as_str().to_lowercase()
|
|
}))
|
|
}
|
|
|
|
pub fn is_path_segment_keyword(&self) -> bool {
|
|
self.is_non_raw_ident_where(Ident::is_path_segment_keyword)
|
|
}
|
|
|
|
/// Don't use this unless you're doing something very loose and heuristic-y.
|
|
pub fn is_any_keyword(&self) -> bool {
|
|
self.is_non_raw_ident_where(Ident::is_any_keyword)
|
|
}
|
|
|
|
/// Returns true for reserved identifiers used internally for elided lifetimes,
|
|
/// unnamed method parameters, crate root module, error recovery etc.
|
|
pub fn is_special_ident(&self) -> bool {
|
|
self.is_non_raw_ident_where(Ident::is_special)
|
|
}
|
|
|
|
/// Returns `true` if the token is a keyword used in the language.
|
|
pub fn is_used_keyword(&self) -> bool {
|
|
self.is_non_raw_ident_where(Ident::is_used_keyword)
|
|
}
|
|
|
|
/// Returns `true` if the token is a keyword reserved for possible future use.
|
|
pub fn is_unused_keyword(&self) -> bool {
|
|
self.is_non_raw_ident_where(Ident::is_unused_keyword)
|
|
}
|
|
|
|
/// Returns `true` if the token is either a special identifier or a keyword.
|
|
pub fn is_reserved_ident(&self) -> bool {
|
|
self.is_non_raw_ident_where(Ident::is_reserved)
|
|
}
|
|
|
|
/// Returns `true` if the token is the identifier `true` or `false`.
|
|
pub fn is_bool_lit(&self) -> bool {
|
|
self.is_non_raw_ident_where(|id| id.name.is_bool_lit())
|
|
}
|
|
|
|
pub fn is_numeric_lit(&self) -> bool {
|
|
matches!(
|
|
self.kind,
|
|
Literal(Lit { kind: LitKind::Integer, .. }) | Literal(Lit { kind: LitKind::Float, .. })
|
|
)
|
|
}
|
|
|
|
/// Returns `true` if the token is the integer literal.
|
|
pub fn is_integer_lit(&self) -> bool {
|
|
matches!(self.kind, Literal(Lit { kind: LitKind::Integer, .. }))
|
|
}
|
|
|
|
/// Returns `true` if the token is a non-raw identifier for which `pred` holds.
|
|
pub fn is_non_raw_ident_where(&self, pred: impl FnOnce(Ident) -> bool) -> bool {
|
|
match self.ident() {
|
|
Some((id, IdentIsRaw::No)) => pred(id),
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
pub fn glue(&self, joint: &Token) -> Option<Token> {
|
|
let kind = match self.kind {
|
|
Eq => match joint.kind {
|
|
Eq => EqEq,
|
|
Gt => FatArrow,
|
|
_ => return None,
|
|
},
|
|
Lt => match joint.kind {
|
|
Eq => Le,
|
|
Lt => BinOp(Shl),
|
|
Le => BinOpEq(Shl),
|
|
BinOp(Minus) => LArrow,
|
|
_ => return None,
|
|
},
|
|
Gt => match joint.kind {
|
|
Eq => Ge,
|
|
Gt => BinOp(Shr),
|
|
Ge => BinOpEq(Shr),
|
|
_ => return None,
|
|
},
|
|
Not => match joint.kind {
|
|
Eq => Ne,
|
|
_ => return None,
|
|
},
|
|
BinOp(op) => match joint.kind {
|
|
Eq => BinOpEq(op),
|
|
BinOp(And) if op == And => AndAnd,
|
|
BinOp(Or) if op == Or => OrOr,
|
|
Gt if op == Minus => RArrow,
|
|
_ => return None,
|
|
},
|
|
Dot => match joint.kind {
|
|
Dot => DotDot,
|
|
DotDot => DotDotDot,
|
|
_ => return None,
|
|
},
|
|
DotDot => match joint.kind {
|
|
Dot => DotDotDot,
|
|
Eq => DotDotEq,
|
|
_ => return None,
|
|
},
|
|
Colon => match joint.kind {
|
|
Colon => PathSep,
|
|
_ => return None,
|
|
},
|
|
SingleQuote => match joint.kind {
|
|
Ident(name, is_raw) => Lifetime(Symbol::intern(&format!("'{name}")), is_raw),
|
|
_ => return None,
|
|
},
|
|
|
|
Le | EqEq | Ne | Ge | AndAnd | OrOr | Tilde | BinOpEq(..) | At | DotDotDot
|
|
| DotDotEq | Comma | Semi | PathSep | RArrow | LArrow | FatArrow | Pound | Dollar
|
|
| Question | OpenDelim(..) | CloseDelim(..) | Literal(..) | Ident(..) | NtIdent(..)
|
|
| Lifetime(..) | NtLifetime(..) | Interpolated(..) | DocComment(..) | Eof => {
|
|
return None;
|
|
}
|
|
};
|
|
|
|
Some(Token::new(kind, self.span.to(joint.span)))
|
|
}
|
|
}
|
|
|
|
impl PartialEq<TokenKind> for Token {
|
|
#[inline]
|
|
fn eq(&self, rhs: &TokenKind) -> bool {
|
|
self.kind == *rhs
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, HashStable_Generic)]
|
|
pub enum NtPatKind {
|
|
// Matches or-patterns. Was written using `pat` in edition 2021 or later.
|
|
PatWithOr,
|
|
// Doesn't match or-patterns.
|
|
// - `inferred`: was written using `pat` in edition 2015 or 2018.
|
|
// - `!inferred`: was written using `pat_param`.
|
|
PatParam { inferred: bool },
|
|
}
|
|
|
|
#[derive(Debug, Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, HashStable_Generic)]
|
|
pub enum NtExprKind {
|
|
// Matches expressions using the post-edition 2024. Was written using
|
|
// `expr` in edition 2024 or later.
|
|
Expr,
|
|
// Matches expressions using the pre-edition 2024 rules.
|
|
// - `inferred`: was written using `expr` in edition 2021 or earlier.
|
|
// - `!inferred`: was written using `expr_2021`.
|
|
Expr2021 { inferred: bool },
|
|
}
|
|
|
|
#[derive(Clone, Encodable, Decodable)]
|
|
/// For interpolation during macro expansion.
|
|
pub enum Nonterminal {
|
|
NtItem(P<ast::Item>),
|
|
NtBlock(P<ast::Block>),
|
|
NtStmt(P<ast::Stmt>),
|
|
NtPat(P<ast::Pat>),
|
|
NtExpr(P<ast::Expr>),
|
|
NtTy(P<ast::Ty>),
|
|
NtLiteral(P<ast::Expr>),
|
|
/// Stuff inside brackets for attributes
|
|
NtMeta(P<ast::AttrItem>),
|
|
NtPath(P<ast::Path>),
|
|
NtVis(P<ast::Visibility>),
|
|
}
|
|
|
|
#[derive(Debug, Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, HashStable_Generic)]
|
|
pub enum NonterminalKind {
|
|
Item,
|
|
Block,
|
|
Stmt,
|
|
Pat(NtPatKind),
|
|
Expr(NtExprKind),
|
|
Ty,
|
|
Ident,
|
|
Lifetime,
|
|
Literal,
|
|
Meta,
|
|
Path,
|
|
Vis,
|
|
TT,
|
|
}
|
|
|
|
impl NonterminalKind {
|
|
/// The `edition` closure is used to get the edition for the given symbol. Doing
|
|
/// `span.edition()` is expensive, so we do it lazily.
|
|
pub fn from_symbol(
|
|
symbol: Symbol,
|
|
edition: impl FnOnce() -> Edition,
|
|
) -> Option<NonterminalKind> {
|
|
Some(match symbol {
|
|
sym::item => NonterminalKind::Item,
|
|
sym::block => NonterminalKind::Block,
|
|
sym::stmt => NonterminalKind::Stmt,
|
|
sym::pat => {
|
|
if edition().at_least_rust_2021() {
|
|
NonterminalKind::Pat(PatWithOr)
|
|
} else {
|
|
NonterminalKind::Pat(PatParam { inferred: true })
|
|
}
|
|
}
|
|
sym::pat_param => NonterminalKind::Pat(PatParam { inferred: false }),
|
|
sym::expr => {
|
|
if edition().at_least_rust_2024() {
|
|
NonterminalKind::Expr(Expr)
|
|
} else {
|
|
NonterminalKind::Expr(Expr2021 { inferred: true })
|
|
}
|
|
}
|
|
sym::expr_2021 => NonterminalKind::Expr(Expr2021 { inferred: false }),
|
|
sym::ty => NonterminalKind::Ty,
|
|
sym::ident => NonterminalKind::Ident,
|
|
sym::lifetime => NonterminalKind::Lifetime,
|
|
sym::literal => NonterminalKind::Literal,
|
|
sym::meta => NonterminalKind::Meta,
|
|
sym::path => NonterminalKind::Path,
|
|
sym::vis => NonterminalKind::Vis,
|
|
sym::tt => NonterminalKind::TT,
|
|
_ => return None,
|
|
})
|
|
}
|
|
|
|
fn symbol(self) -> Symbol {
|
|
match self {
|
|
NonterminalKind::Item => sym::item,
|
|
NonterminalKind::Block => sym::block,
|
|
NonterminalKind::Stmt => sym::stmt,
|
|
NonterminalKind::Pat(PatParam { inferred: true } | PatWithOr) => sym::pat,
|
|
NonterminalKind::Pat(PatParam { inferred: false }) => sym::pat_param,
|
|
NonterminalKind::Expr(Expr2021 { inferred: true } | Expr) => sym::expr,
|
|
NonterminalKind::Expr(Expr2021 { inferred: false }) => sym::expr_2021,
|
|
NonterminalKind::Ty => sym::ty,
|
|
NonterminalKind::Ident => sym::ident,
|
|
NonterminalKind::Lifetime => sym::lifetime,
|
|
NonterminalKind::Literal => sym::literal,
|
|
NonterminalKind::Meta => sym::meta,
|
|
NonterminalKind::Path => sym::path,
|
|
NonterminalKind::Vis => sym::vis,
|
|
NonterminalKind::TT => sym::tt,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl fmt::Display for NonterminalKind {
|
|
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
|
write!(f, "{}", self.symbol())
|
|
}
|
|
}
|
|
|
|
impl Nonterminal {
|
|
pub fn use_span(&self) -> Span {
|
|
match self {
|
|
NtItem(item) => item.span,
|
|
NtBlock(block) => block.span,
|
|
NtStmt(stmt) => stmt.span,
|
|
NtPat(pat) => pat.span,
|
|
NtExpr(expr) | NtLiteral(expr) => expr.span,
|
|
NtTy(ty) => ty.span,
|
|
NtMeta(attr_item) => attr_item.span(),
|
|
NtPath(path) => path.span,
|
|
NtVis(vis) => vis.span,
|
|
}
|
|
}
|
|
|
|
pub fn descr(&self) -> &'static str {
|
|
match self {
|
|
NtItem(..) => "item",
|
|
NtBlock(..) => "block",
|
|
NtStmt(..) => "statement",
|
|
NtPat(..) => "pattern",
|
|
NtExpr(..) => "expression",
|
|
NtLiteral(..) => "literal",
|
|
NtTy(..) => "type",
|
|
NtMeta(..) => "attribute",
|
|
NtPath(..) => "path",
|
|
NtVis(..) => "visibility",
|
|
}
|
|
}
|
|
}
|
|
|
|
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 {
|
|
NtItem(..) => f.pad("NtItem(..)"),
|
|
NtBlock(..) => f.pad("NtBlock(..)"),
|
|
NtStmt(..) => f.pad("NtStmt(..)"),
|
|
NtPat(..) => f.pad("NtPat(..)"),
|
|
NtExpr(..) => f.pad("NtExpr(..)"),
|
|
NtTy(..) => f.pad("NtTy(..)"),
|
|
NtLiteral(..) => f.pad("NtLiteral(..)"),
|
|
NtMeta(..) => f.pad("NtMeta(..)"),
|
|
NtPath(..) => f.pad("NtPath(..)"),
|
|
NtVis(..) => f.pad("NtVis(..)"),
|
|
}
|
|
}
|
|
}
|
|
|
|
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 {
|
|
use rustc_data_structures::static_assert_size;
|
|
|
|
use super::*;
|
|
// tidy-alphabetical-start
|
|
static_assert_size!(Lit, 12);
|
|
static_assert_size!(LitKind, 2);
|
|
static_assert_size!(Nonterminal, 16);
|
|
static_assert_size!(Token, 24);
|
|
static_assert_size!(TokenKind, 16);
|
|
// tidy-alphabetical-end
|
|
}
|