407 lines
12 KiB
Rust
407 lines
12 KiB
Rust
|
|
||
|
|
||
|
// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
|
||
|
// file at the top-level directory of this distribution and at
|
||
|
// http://rust-lang.org/COPYRIGHT.
|
||
|
//
|
||
|
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
|
||
|
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
|
||
|
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
|
||
|
// option. This file may not be copied, modified, or distributed
|
||
|
// except according to those terms.
|
||
|
|
||
|
pub use self::BinOpToken::*;
|
||
|
pub use self::Nonterminal::*;
|
||
|
pub use self::DelimToken::*;
|
||
|
pub use self::Lit::*;
|
||
|
pub use self::Token::*;
|
||
|
|
||
|
use ast::{self};
|
||
|
use ptr::P;
|
||
|
use symbol::keywords;
|
||
|
use tokenstream::TokenTree;
|
||
|
|
||
|
use std::fmt;
|
||
|
use std::rc::Rc;
|
||
|
|
||
|
#[derive(Clone, RustcEncodable, RustcDecodable, PartialEq, Eq, Hash, Debug, Copy)]
|
||
|
pub enum BinOpToken {
|
||
|
Plus,
|
||
|
Minus,
|
||
|
Star,
|
||
|
Slash,
|
||
|
Percent,
|
||
|
Caret,
|
||
|
And,
|
||
|
Or,
|
||
|
Shl,
|
||
|
Shr,
|
||
|
}
|
||
|
|
||
|
/// A delimiter token
|
||
|
#[derive(Clone, RustcEncodable, RustcDecodable, PartialEq, Eq, Hash, Debug, Copy)]
|
||
|
pub enum DelimToken {
|
||
|
/// A round parenthesis: `(` or `)`
|
||
|
Paren,
|
||
|
/// A square bracket: `[` or `]`
|
||
|
Bracket,
|
||
|
/// A curly brace: `{` or `}`
|
||
|
Brace,
|
||
|
/// An empty delimiter
|
||
|
NoDelim,
|
||
|
}
|
||
|
|
||
|
impl DelimToken {
|
||
|
pub fn len(self) -> usize {
|
||
|
if self == NoDelim { 0 } else { 1 }
|
||
|
}
|
||
|
|
||
|
pub fn is_empty(self) -> bool {
|
||
|
self == NoDelim
|
||
|
}
|
||
|
}
|
||
|
|
||
|
#[derive(Clone, RustcEncodable, RustcDecodable, PartialEq, Eq, Hash, Debug, Copy)]
|
||
|
pub enum Lit {
|
||
|
Byte(ast::Name),
|
||
|
Char(ast::Name),
|
||
|
Integer(ast::Name),
|
||
|
Float(ast::Name),
|
||
|
Str_(ast::Name),
|
||
|
StrRaw(ast::Name, usize), /* raw str delimited by n hash symbols */
|
||
|
ByteStr(ast::Name),
|
||
|
ByteStrRaw(ast::Name, usize), /* raw byte str delimited by n hash symbols */
|
||
|
}
|
||
|
|
||
|
impl Lit {
|
||
|
pub fn short_name(&self) -> &'static str {
|
||
|
match *self {
|
||
|
Byte(_) => "byte",
|
||
|
Char(_) => "char",
|
||
|
Integer(_) => "integer",
|
||
|
Float(_) => "float",
|
||
|
Str_(_) | StrRaw(..) => "string",
|
||
|
ByteStr(_) | ByteStrRaw(..) => "byte string"
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
fn ident_can_begin_expr(ident: ast::Ident) -> bool {
|
||
|
let ident_token: Token = Ident(ident);
|
||
|
|
||
|
!ident_token.is_any_keyword() ||
|
||
|
ident_token.is_path_segment_keyword() ||
|
||
|
[
|
||
|
keywords::Do.name(),
|
||
|
keywords::Box.name(),
|
||
|
keywords::Break.name(),
|
||
|
keywords::Continue.name(),
|
||
|
keywords::False.name(),
|
||
|
keywords::For.name(),
|
||
|
keywords::If.name(),
|
||
|
keywords::Loop.name(),
|
||
|
keywords::Match.name(),
|
||
|
keywords::Move.name(),
|
||
|
keywords::Return.name(),
|
||
|
keywords::True.name(),
|
||
|
keywords::Unsafe.name(),
|
||
|
keywords::While.name(),
|
||
|
].contains(&ident.name)
|
||
|
}
|
||
|
|
||
|
fn ident_can_begin_type(ident: ast::Ident) -> bool {
|
||
|
let ident_token: Token = Ident(ident);
|
||
|
|
||
|
!ident_token.is_any_keyword() ||
|
||
|
ident_token.is_path_segment_keyword() ||
|
||
|
[
|
||
|
keywords::For.name(),
|
||
|
keywords::Impl.name(),
|
||
|
keywords::Fn.name(),
|
||
|
keywords::Unsafe.name(),
|
||
|
keywords::Extern.name(),
|
||
|
keywords::Typeof.name(),
|
||
|
].contains(&ident.name)
|
||
|
}
|
||
|
|
||
|
#[derive(Clone, RustcEncodable, RustcDecodable, PartialEq, Eq, Hash, Debug)]
|
||
|
pub enum Token {
|
||
|
/* Expression-operator symbols. */
|
||
|
Eq,
|
||
|
Lt,
|
||
|
Le,
|
||
|
EqEq,
|
||
|
Ne,
|
||
|
Ge,
|
||
|
Gt,
|
||
|
AndAnd,
|
||
|
OrOr,
|
||
|
Not,
|
||
|
Tilde,
|
||
|
BinOp(BinOpToken),
|
||
|
BinOpEq(BinOpToken),
|
||
|
|
||
|
/* Structural symbols */
|
||
|
At,
|
||
|
Dot,
|
||
|
DotDot,
|
||
|
DotDotDot,
|
||
|
Comma,
|
||
|
Semi,
|
||
|
Colon,
|
||
|
ModSep,
|
||
|
RArrow,
|
||
|
LArrow,
|
||
|
FatArrow,
|
||
|
Pound,
|
||
|
Dollar,
|
||
|
Question,
|
||
|
/// An opening delimiter, eg. `{`
|
||
|
OpenDelim(DelimToken),
|
||
|
/// A closing delimiter, eg. `}`
|
||
|
CloseDelim(DelimToken),
|
||
|
|
||
|
/* Literals */
|
||
|
Literal(Lit, Option<ast::Name>),
|
||
|
|
||
|
/* Name components */
|
||
|
Ident(ast::Ident),
|
||
|
Underscore,
|
||
|
Lifetime(ast::Ident),
|
||
|
|
||
|
/* For interpolation */
|
||
|
Interpolated(Rc<Nonterminal>),
|
||
|
// Can be expanded into several tokens.
|
||
|
/// Doc comment
|
||
|
DocComment(ast::Name),
|
||
|
// In right-hand-sides of MBE macros:
|
||
|
/// A syntactic variable that will be filled in by macro expansion.
|
||
|
SubstNt(ast::Ident),
|
||
|
|
||
|
// Junk. These carry no data because we don't really care about the data
|
||
|
// they *would* carry, and don't really want to allocate a new ident for
|
||
|
// them. Instead, users could extract that from the associated span.
|
||
|
|
||
|
/// Whitespace
|
||
|
Whitespace,
|
||
|
/// Comment
|
||
|
Comment,
|
||
|
Shebang(ast::Name),
|
||
|
|
||
|
Eof,
|
||
|
}
|
||
|
|
||
|
impl Token {
|
||
|
/// Returns `true` if the token starts with '>'.
|
||
|
pub fn is_like_gt(&self) -> bool {
|
||
|
match *self {
|
||
|
BinOp(Shr) | BinOpEq(Shr) | Gt | Ge => true,
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token can appear at the start of an expression.
|
||
|
pub fn can_begin_expr(&self) -> bool {
|
||
|
match *self {
|
||
|
Ident(ident) => ident_can_begin_expr(ident), // value name or keyword
|
||
|
OpenDelim(..) | // 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
|
||
|
DotDot | DotDotDot | // range notation
|
||
|
Lt | BinOp(Shl) | // associated path
|
||
|
ModSep | // global path
|
||
|
Pound => true, // expression attributes
|
||
|
Interpolated(ref nt) => match **nt {
|
||
|
NtIdent(..) | NtExpr(..) | NtBlock(..) | NtPath(..) => true,
|
||
|
_ => false,
|
||
|
},
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token can appear at the start of a type.
|
||
|
pub fn can_begin_type(&self) -> bool {
|
||
|
match *self {
|
||
|
Ident(ident) => ident_can_begin_type(ident), // type name or keyword
|
||
|
OpenDelim(Paren) | // tuple
|
||
|
OpenDelim(Bracket) | // array
|
||
|
Underscore | // placeholder
|
||
|
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
|
||
|
ModSep => true, // global path
|
||
|
Interpolated(ref nt) => match **nt {
|
||
|
NtIdent(..) | NtTy(..) | NtPath(..) => true,
|
||
|
_ => false,
|
||
|
},
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is any literal
|
||
|
pub fn is_lit(&self) -> bool {
|
||
|
match *self {
|
||
|
Literal(..) => true,
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
pub fn ident(&self) -> Option<ast::Ident> {
|
||
|
match *self {
|
||
|
Ident(ident) => Some(ident),
|
||
|
Interpolated(ref nt) => match **nt {
|
||
|
NtIdent(ident) => Some(ident.node),
|
||
|
_ => 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 documentation comment.
|
||
|
pub fn is_doc_comment(&self) -> bool {
|
||
|
match *self {
|
||
|
DocComment(..) => true,
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is interpolated.
|
||
|
pub fn is_interpolated(&self) -> bool {
|
||
|
match *self {
|
||
|
Interpolated(..) => true,
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is an interpolated path.
|
||
|
pub fn is_path(&self) -> bool {
|
||
|
if let Interpolated(ref nt) = *self {
|
||
|
if let NtPath(..) = **nt {
|
||
|
return true;
|
||
|
}
|
||
|
}
|
||
|
false
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is a lifetime.
|
||
|
pub fn is_lifetime(&self) -> bool {
|
||
|
match *self {
|
||
|
Lifetime(..) => true,
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is either the `mut` or `const` keyword.
|
||
|
pub fn is_mutability(&self) -> bool {
|
||
|
self.is_keyword(keywords::Mut) ||
|
||
|
self.is_keyword(keywords::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_any_keyword()
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is a given keyword, `kw`.
|
||
|
pub fn is_keyword(&self, kw: keywords::Keyword) -> bool {
|
||
|
self.ident().map(|ident| ident.name == kw.name()).unwrap_or(false)
|
||
|
}
|
||
|
|
||
|
pub fn is_path_segment_keyword(&self) -> bool {
|
||
|
match self.ident() {
|
||
|
Some(id) => id.name == keywords::Super.name() ||
|
||
|
id.name == keywords::SelfValue.name() ||
|
||
|
id.name == keywords::SelfType.name(),
|
||
|
None => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is either a strict or reserved keyword.
|
||
|
pub fn is_any_keyword(&self) -> bool {
|
||
|
self.is_strict_keyword() || self.is_reserved_keyword()
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is a strict keyword.
|
||
|
pub fn is_strict_keyword(&self) -> bool {
|
||
|
match self.ident() {
|
||
|
Some(id) => id.name >= keywords::As.name() && id.name <= keywords::While.name(),
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// Returns `true` if the token is a keyword reserved for possible future use.
|
||
|
pub fn is_reserved_keyword(&self) -> bool {
|
||
|
match self.ident() {
|
||
|
Some(id) => id.name >= keywords::Abstract.name() && id.name <= keywords::Yield.name(),
|
||
|
_ => false,
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
#[derive(Clone, RustcEncodable, RustcDecodable, PartialEq, Eq, Hash)]
|
||
|
/// For interpolation during macro expansion.
|
||
|
pub enum Nonterminal {
|
||
|
NtItem(P<ast::Item>),
|
||
|
NtBlock(P<ast::Block>),
|
||
|
NtStmt(ast::Stmt),
|
||
|
NtPat(P<ast::Pat>),
|
||
|
NtExpr(P<ast::Expr>),
|
||
|
NtTy(P<ast::Ty>),
|
||
|
NtIdent(ast::SpannedIdent),
|
||
|
/// Stuff inside brackets for attributes
|
||
|
NtMeta(ast::MetaItem),
|
||
|
NtPath(ast::Path),
|
||
|
NtVis(ast::Visibility),
|
||
|
NtTT(TokenTree),
|
||
|
// These are not exposed to macros, but are used by quasiquote.
|
||
|
NtArm(ast::Arm),
|
||
|
NtImplItem(ast::ImplItem),
|
||
|
NtTraitItem(ast::TraitItem),
|
||
|
NtGenerics(ast::Generics),
|
||
|
NtWhereClause(ast::WhereClause),
|
||
|
NtArg(ast::Arg),
|
||
|
}
|
||
|
|
||
|
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(..)"),
|
||
|
NtMeta(..) => f.pad("NtMeta(..)"),
|
||
|
NtPath(..) => f.pad("NtPath(..)"),
|
||
|
NtTT(..) => f.pad("NtTT(..)"),
|
||
|
NtArm(..) => f.pad("NtArm(..)"),
|
||
|
NtImplItem(..) => f.pad("NtImplItem(..)"),
|
||
|
NtTraitItem(..) => f.pad("NtTraitItem(..)"),
|
||
|
NtGenerics(..) => f.pad("NtGenerics(..)"),
|
||
|
NtWhereClause(..) => f.pad("NtWhereClause(..)"),
|
||
|
NtArg(..) => f.pad("NtArg(..)"),
|
||
|
NtVis(..) => f.pad("NtVis(..)"),
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
|