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use super::parser::{Parser, TokenSet};
use SyntaxKind;
use syntax_kinds::*;
mod items;
mod attributes;
mod expressions;
mod types;
mod paths;
pub(crate) fn file(p: &mut Parser) {
let file = p.start();
p.eat(SHEBANG);
items::mod_contents(p, false);
file.complete(p, FILE);
}
fn visibility(p: &mut Parser) {
if p.at(PUB_KW) {
let vis = p.start();
p.bump();
if p.at(L_PAREN) {
match p.nth(1) {
CRATE_KW | SELF_KW | SUPER_KW => {
p.bump();
p.bump();
p.expect(R_PAREN);
}
IN_KW => {
p.bump();
p.bump();
paths::use_path(p);
p.expect(R_PAREN);
}
_ => (),
}
}
vis.complete(p, VISIBILITY);
}
}
fn alias(p: &mut Parser) -> bool {
if p.at(AS_KW) {
let alias = p.start();
p.bump();
p.expect(IDENT);
alias.complete(p, ALIAS);
}
true //FIXME: return false if three are errors
}
impl<'p> Parser<'p> {
fn at<L: Lookahead>(&self, l: L) -> bool {
l.is_ahead(self)
}
fn err_and_bump(&mut self, message: &str) {
let err = self.start();
self.error().message(message).emit();
self.bump();
err.complete(self, ERROR);
}
fn expect(&mut self, kind: SyntaxKind) -> bool {
if self.at(kind) {
self.bump();
true
} else {
self.error().message(format!("expected {:?}", kind)).emit();
false
}
}
fn eat(&mut self, kind: SyntaxKind) -> bool {
self.current() == kind && {
self.bump();
true
}
}
}
trait Lookahead: Copy {
fn is_ahead(self, p: &Parser) -> bool;
}
impl Lookahead for SyntaxKind {
fn is_ahead(self, p: &Parser) -> bool {
p.current() == self
}
}
impl Lookahead for [SyntaxKind; 2] {
fn is_ahead(self, p: &Parser) -> bool {
p.current() == self[0] && p.nth(1) == self[1]
}
}
impl Lookahead for [SyntaxKind; 3] {
fn is_ahead(self, p: &Parser) -> bool {
p.current() == self[0] && p.nth(1) == self[1] && p.nth(2) == self[2]
}
}
#[derive(Clone, Copy)]
struct AnyOf<'a>(&'a [SyntaxKind]);
impl<'a> Lookahead for AnyOf<'a> {
fn is_ahead(self, p: &Parser) -> bool {
let curr = p.current();
self.0.iter().any(|&k| k == curr)
}
}
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