358a603f11
Instead of `ast::Lit`. Literal lowering now happens at two different times. Expression literals are lowered when HIR is crated. Attribute literals are lowered during parsing. This commit changes the language very slightly. Some programs that used to not compile now will compile. This is because some invalid literals that are removed by `cfg` or attribute macros will no longer trigger errors. See this comment for more details: https://github.com/rust-lang/rust/pull/102944#issuecomment-1277476773
943 lines
32 KiB
Rust
943 lines
32 KiB
Rust
pub use BinOpToken::*;
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pub use LitKind::*;
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pub use Nonterminal::*;
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pub use TokenKind::*;
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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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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::HashStable_Generic;
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use rustc_span::symbol::{kw, sym};
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use rustc_span::symbol::{Ident, Symbol};
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use rustc_span::{self, edition::Edition, Span, DUMMY_SP};
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use std::borrow::Cow;
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use std::fmt;
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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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/// 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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/// The `None` variant is also renamed to `Invisible` to be
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/// less confusing and better convey the semantics.
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#[derive(Copy, Clone, Debug, PartialEq, Eq)]
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#[derive(Encodable, Decodable, Hash, 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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/// `Ø ... Ø`
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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,
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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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Err,
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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_or_bool` 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, false) if name.is_bool_lit() => {
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Some(Lit::new(Bool, name, None))
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}
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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.clone())
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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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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 => panic!("literal token contains `Lit::Bool`"),
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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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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: bool) -> 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::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::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: bool) -> 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(Clone, PartialEq, Encodable, Decodable, Debug, HashStable_Generic)]
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pub enum TokenKind {
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/* Expression-operator symbols. */
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Eq,
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Lt,
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Le,
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EqEq,
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Ne,
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Ge,
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Gt,
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AndAnd,
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OrOr,
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Not,
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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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At,
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Dot,
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DotDot,
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DotDotDot,
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DotDotEq,
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Comma,
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Semi,
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Colon,
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ModSep,
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RArrow,
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LArrow,
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FatArrow,
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Pound,
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Dollar,
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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, /* is_raw */ bool),
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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),
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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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Interpolated(Lrc<Nonterminal>),
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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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Eof,
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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 {
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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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}
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// An approximation to proc-macro-style single-character operators used by rustc parser.
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// If the operator token can be broken into two tokens, the first of which is single-character,
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// then this function performs that operation, otherwise it returns `None`.
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pub fn break_two_token_op(&self) -> Option<(TokenKind, TokenKind)> {
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Some(match *self {
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Le => (Lt, Eq),
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EqEq => (Eq, Eq),
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Ne => (Not, Eq),
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Ge => (Gt, Eq),
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AndAnd => (BinOp(And), BinOp(And)),
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OrOr => (BinOp(Or), BinOp(Or)),
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BinOp(Shl) => (Lt, Lt),
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BinOp(Shr) => (Gt, Gt),
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BinOpEq(Plus) => (BinOp(Plus), Eq),
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BinOpEq(Minus) => (BinOp(Minus), Eq),
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BinOpEq(Star) => (BinOp(Star), Eq),
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BinOpEq(Slash) => (BinOp(Slash), Eq),
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BinOpEq(Percent) => (BinOp(Percent), Eq),
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BinOpEq(Caret) => (BinOp(Caret), Eq),
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BinOpEq(And) => (BinOp(And), Eq),
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BinOpEq(Or) => (BinOp(Or), Eq),
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BinOpEq(Shl) => (Lt, Le),
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BinOpEq(Shr) => (Gt, Ge),
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DotDot => (Dot, Dot),
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DotDotDot => (Dot, DotDot),
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ModSep => (Colon, Colon),
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RArrow => (BinOp(Minus), Gt),
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LArrow => (Lt, BinOp(Minus)),
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FatArrow => (Eq, Gt),
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_ => return None,
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})
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}
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/// Returns tokens that are likely to be typed accidentally instead of the current token.
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/// Enables better error recovery when the wrong token is found.
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pub fn similar_tokens(&self) -> Option<Vec<TokenKind>> {
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match *self {
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Comma => Some(vec![Dot, Lt, Semi]),
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Semi => Some(vec![Colon, Comma]),
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FatArrow => Some(vec![Eq, RArrow]),
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_ => None,
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}
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}
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pub fn should_end_const_arg(&self) -> bool {
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matches!(self, Gt | Ge | BinOp(Shr) | BinOpEq(Shr))
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}
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}
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impl Token {
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pub fn new(kind: TokenKind, span: Span) -> Self {
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Token { kind, span }
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}
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/// Some token that will be thrown away later.
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pub fn dummy() -> Self {
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Token::new(TokenKind::Question, DUMMY_SP)
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}
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/// Recovers a `Token` from an `Ident`. This creates a raw identifier if necessary.
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pub fn from_ast_ident(ident: Ident) -> Self {
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Token::new(Ident(ident.name, ident.is_raw_guess()), ident.span)
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}
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/// For interpolated tokens, returns a span of the fragment to which the interpolated
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/// token refers. For all other tokens this is just a regular span.
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/// It is particularly important to use this for identifiers and lifetimes
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/// for which spans affect name resolution and edition checks.
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/// Note that keywords are also identifiers, so they should use this
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/// if they keep spans or perform edition checks.
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pub fn uninterpolated_span(&self) -> Span {
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match &self.kind {
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Interpolated(nt) => nt.span(),
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_ => self.span,
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}
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}
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pub fn is_op(&self) -> bool {
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match self.kind {
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Eq | Lt | Le | EqEq | Ne | Ge | Gt | AndAnd | OrOr | Not | Tilde | BinOp(_)
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| BinOpEq(_) | At | Dot | DotDot | DotDotDot | DotDotEq | Comma | Semi | Colon
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| ModSep | RArrow | LArrow | FatArrow | Pound | Dollar | Question | SingleQuote => true,
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OpenDelim(..) | CloseDelim(..) | Literal(..) | DocComment(..) | Ident(..)
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| Lifetime(..) | Interpolated(..) | Eof => false,
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}
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}
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pub fn is_like_plus(&self) -> bool {
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matches!(self.kind, BinOp(Plus) | BinOpEq(Plus))
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}
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/// Returns `true` if the token can appear at the start of an expression.
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pub fn can_begin_expr(&self) -> bool {
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match self.uninterpolate().kind {
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Ident(name, is_raw) =>
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ident_can_begin_expr(name, self.span, is_raw), // value name or keyword
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OpenDelim(..) | // tuple, array or block
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Literal(..) | // literal
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Not | // operator not
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BinOp(Minus) | // unary minus
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BinOp(Star) | // dereference
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BinOp(Or) | OrOr | // closure
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BinOp(And) | // reference
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AndAnd | // double reference
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// DotDotDot is no longer supported, but we need some way to display the error
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DotDot | DotDotDot | DotDotEq | // range notation
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Lt | BinOp(Shl) | // associated path
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ModSep | // global path
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Lifetime(..) | // labeled loop
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Pound => true, // expression attributes
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Interpolated(ref nt) => matches!(**nt, NtLiteral(..) |
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NtExpr(..) |
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NtBlock(..) |
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NtPath(..)),
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_ => false,
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}
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}
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|
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/// Returns `true` if the token can appear at the start of an pattern.
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///
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/// Shamelessly borrowed from `can_begin_expr`, only used for diagnostics right now.
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pub fn can_begin_pattern(&self) -> bool {
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match self.uninterpolate().kind {
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Ident(name, is_raw) =>
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ident_can_begin_expr(name, self.span, is_raw), // value name or keyword
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| OpenDelim(Delimiter::Bracket | Delimiter::Parenthesis) // tuple or array
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| Literal(..) // literal
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| BinOp(Minus) // unary minus
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| BinOp(And) // reference
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| AndAnd // double reference
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// DotDotDot is no longer supported
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| DotDot | DotDotDot | DotDotEq // ranges
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| Lt | BinOp(Shl) // associated path
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| ModSep => true, // global path
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Interpolated(ref nt) => matches!(**nt, NtLiteral(..) |
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NtPat(..) |
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NtBlock(..) |
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NtPath(..)),
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_ => false,
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}
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}
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|
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/// Returns `true` if the token can appear at the start of a type.
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pub fn can_begin_type(&self) -> bool {
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match self.uninterpolate().kind {
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Ident(name, is_raw) =>
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ident_can_begin_type(name, self.span, is_raw), // type name or keyword
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OpenDelim(Delimiter::Parenthesis) | // tuple
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OpenDelim(Delimiter::Bracket) | // array
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Not | // never
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BinOp(Star) | // raw pointer
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BinOp(And) | // reference
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AndAnd | // double reference
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Question | // maybe bound in trait object
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Lifetime(..) | // lifetime bound in trait object
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Lt | BinOp(Shl) | // associated path
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ModSep => true, // global path
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Interpolated(ref nt) => matches!(**nt, NtTy(..) | NtPath(..)),
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_ => false,
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}
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}
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|
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/// Returns `true` if the token can appear at the start of a const param.
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|
pub fn can_begin_const_arg(&self) -> bool {
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match self.kind {
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OpenDelim(Delimiter::Brace) => true,
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Interpolated(ref nt) => matches!(**nt, NtExpr(..) | NtBlock(..) | NtLiteral(..)),
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_ => self.can_begin_literal_maybe_minus(),
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}
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}
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|
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/// Returns `true` if the token can appear at the start of a generic bound.
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|
pub fn can_begin_bound(&self) -> bool {
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self.is_path_start()
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|| self.is_lifetime()
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|| self.is_keyword(kw::For)
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|| self == &Question
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|| self == &OpenDelim(Delimiter::Parenthesis)
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}
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|
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/// Returns `true` if the token can appear at the start of an item.
|
|
pub fn can_begin_item(&self) -> bool {
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|
match self.kind {
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|
Ident(name, _) => [
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|
kw::Fn,
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|
kw::Use,
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|
kw::Struct,
|
|
kw::Enum,
|
|
kw::Pub,
|
|
kw::Trait,
|
|
kw::Extern,
|
|
kw::Impl,
|
|
kw::Unsafe,
|
|
kw::Const,
|
|
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, false) 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,
|
|
},
|
|
_ => 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 {
|
|
Interpolated(nt) => match **nt {
|
|
NtIdent(ident, is_raw) => {
|
|
Cow::Owned(Token::new(Ident(ident.name, is_raw), ident.span))
|
|
}
|
|
NtLifetime(ident) => Cow::Owned(Token::new(Lifetime(ident.name), ident.span)),
|
|
_ => Cow::Borrowed(self),
|
|
},
|
|
_ => Cow::Borrowed(self),
|
|
}
|
|
}
|
|
|
|
/// Returns an identifier if this token is an identifier.
|
|
#[inline]
|
|
pub fn ident(&self) -> Option<(Ident, /* is_raw */ bool)> {
|
|
// 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)),
|
|
Interpolated(nt) => match **nt {
|
|
NtIdent(ident, is_raw) => Some((ident, is_raw)),
|
|
_ => None,
|
|
},
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
/// Returns a lifetime identifier if this token is a lifetime.
|
|
#[inline]
|
|
pub fn lifetime(&self) -> Option<Ident> {
|
|
// We avoid using `Token::uninterpolate` here because it's slow.
|
|
match &self.kind {
|
|
&Lifetime(name) => Some(Ident::new(name, self.span)),
|
|
Interpolated(nt) => match **nt {
|
|
NtLifetime(ident) => Some(ident),
|
|
_ => None,
|
|
},
|
|
_ => 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().map_or(false, |(ident, _)| ident.name == name)
|
|
}
|
|
|
|
/// Returns `true` if the token is an interpolated path.
|
|
fn is_path(&self) -> bool {
|
|
if let Interpolated(ref nt) = self.kind && let NtPath(..) = **nt {
|
|
return true;
|
|
}
|
|
false
|
|
}
|
|
|
|
/// Would `maybe_whole_expr` in `parser.rs` return `Ok(..)`?
|
|
/// 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
|
|
&& 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(ref 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 == &ModSep
|
|
|| self.is_qpath_start()
|
|
|| self.is_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)
|
|
}
|
|
|
|
// 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 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, false)) => 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 => ModSep,
|
|
_ => return None,
|
|
},
|
|
SingleQuote => match joint.kind {
|
|
Ident(name, false) => Lifetime(Symbol::intern(&format!("'{}", name))),
|
|
_ => return None,
|
|
},
|
|
|
|
Le | EqEq | Ne | Ge | AndAnd | OrOr | Tilde | BinOpEq(..) | At | DotDotDot
|
|
| DotDotEq | Comma | Semi | ModSep | RArrow | LArrow | FatArrow | Pound | Dollar
|
|
| Question | OpenDelim(..) | CloseDelim(..) | Literal(..) | Ident(..)
|
|
| Lifetime(..) | 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(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>),
|
|
NtIdent(Ident, /* is_raw */ bool),
|
|
NtLifetime(Ident),
|
|
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, Encodable, Decodable)]
|
|
pub enum NonterminalKind {
|
|
Item,
|
|
Block,
|
|
Stmt,
|
|
PatParam {
|
|
/// Keep track of whether the user used `:pat_param` or `:pat` and we inferred it from the
|
|
/// edition of the span. This is used for diagnostics.
|
|
inferred: bool,
|
|
},
|
|
PatWithOr,
|
|
Expr,
|
|
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 => match edition() {
|
|
Edition::Edition2015 | Edition::Edition2018 => {
|
|
NonterminalKind::PatParam { inferred: true }
|
|
}
|
|
Edition::Edition2021 | Edition::Edition2024 => NonterminalKind::PatWithOr,
|
|
},
|
|
sym::pat_param => NonterminalKind::PatParam { inferred: false },
|
|
sym::expr => NonterminalKind::Expr,
|
|
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::PatParam { inferred: false } => sym::pat_param,
|
|
NonterminalKind::PatParam { inferred: true } | NonterminalKind::PatWithOr => sym::pat,
|
|
NonterminalKind::Expr => sym::expr,
|
|
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 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,
|
|
NtIdent(ident, _) | NtLifetime(ident) => ident.span,
|
|
NtMeta(attr_item) => attr_item.span(),
|
|
NtPath(path) => path.span,
|
|
NtVis(vis) => vis.span,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl PartialEq for Nonterminal {
|
|
fn eq(&self, rhs: &Self) -> bool {
|
|
match (self, rhs) {
|
|
(NtIdent(ident_lhs, is_raw_lhs), NtIdent(ident_rhs, is_raw_rhs)) => {
|
|
ident_lhs == ident_rhs && is_raw_lhs == is_raw_rhs
|
|
}
|
|
(NtLifetime(ident_lhs), NtLifetime(ident_rhs)) => ident_lhs == ident_rhs,
|
|
// FIXME: Assume that all "complex" nonterminal 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(..)"),
|
|
NtIdent(..) => f.pad("NtIdent(..)"),
|
|
NtLiteral(..) => f.pad("NtLiteral(..)"),
|
|
NtMeta(..) => f.pad("NtMeta(..)"),
|
|
NtPath(..) => f.pad("NtPath(..)"),
|
|
NtVis(..) => f.pad("NtVis(..)"),
|
|
NtLifetime(..) => f.pad("NtLifetime(..)"),
|
|
}
|
|
}
|
|
}
|
|
|
|
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(all(target_arch = "x86_64", target_pointer_width = "64"))]
|
|
mod size_asserts {
|
|
use super::*;
|
|
use rustc_data_structures::static_assert_size;
|
|
// 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
|
|
}
|