rust/src/parser/event_parser/grammar/items/mod.rs
2018-02-04 12:28:30 +03:00

179 lines
4.2 KiB
Rust

use super::*;
mod structs;
mod use_item;
mod consts;
pub(super) fn mod_contents(p: &mut Parser, stop_on_r_curly: bool) {
attributes::inner_attributes(p);
while !p.at(EOF) && !(stop_on_r_curly && p.at(R_CURLY)) {
item(p);
}
}
pub(super) const ITEM_FIRST: TokenSet = token_set![
EXTERN_KW, MOD_KW, USE_KW, STRUCT_KW, ENUM_KW, FN_KW, PUB_KW, POUND
];
fn item(p: &mut Parser) {
let item = p.start();
attributes::outer_attributes(p);
visibility(p);
let la = p.nth(1);
let item_kind = match p.current() {
USE_KW => {
use_item::use_item(p);
USE_ITEM
}
// test extern_crate
// extern crate foo;
EXTERN_KW if la == CRATE_KW => {
extern_crate_item(p);
EXTERN_CRATE_ITEM
}
EXTERN_KW => {
abi(p);
match p.current() {
// test extern_fn
// extern fn foo() {}
FN_KW => {
fn_item(p);
FN_ITEM
}
// test extern_block
// extern {}
L_CURLY => {
extern_block(p);
EXTERN_BLOCK
}
// test extern_struct
// extern struct Foo;
_ => {
item.abandon(p);
p.error().message("expected `fn` or `{`").emit();
return;
}
}
}
STATIC_KW => {
consts::static_item(p);
STATIC_ITEM
}
CONST_KW => match p.nth(1) {
// test const_fn
// const fn foo() {}
FN_KW => {
p.bump();
fn_item(p);
FN_ITEM
}
// test const_unsafe_fn
// const unsafe fn foo() {}
UNSAFE_KW if p.nth(2) == FN_KW => {
p.bump();
p.bump();
fn_item(p);
FN_ITEM
}
_ => {
consts::const_item(p);
CONST_ITEM
}
},
MOD_KW => {
mod_item(p);
MOD_ITEM
}
STRUCT_KW => {
structs::struct_item(p);
STRUCT_ITEM
}
ENUM_KW => {
structs::enum_item(p);
ENUM_ITEM
}
FN_KW => {
fn_item(p);
FN_ITEM
}
L_CURLY => {
item.abandon(p);
error_block(p, "expected item");
return;
}
err_token => {
item.abandon(p);
let message = if err_token == SEMI {
//TODO: if the item is incomplete, this message is misleading
"expected item, found `;`\n\
consider removing this semicolon"
} else {
"expected item"
};
p.err_and_bump(message);
return;
}
};
item.complete(p, item_kind);
}
fn extern_crate_item(p: &mut Parser) {
assert!(p.at(EXTERN_KW));
p.bump();
assert!(p.at(CRATE_KW));
p.bump();
p.expect(IDENT) && alias(p) && p.expect(SEMI);
}
fn extern_block(p: &mut Parser) {
assert!(p.at(L_CURLY));
p.bump();
p.expect(R_CURLY);
}
fn mod_item(p: &mut Parser) {
assert!(p.at(MOD_KW));
p.bump();
if p.expect(IDENT) && !p.eat(SEMI) {
if p.expect(L_CURLY) {
mod_contents(p, true);
p.expect(R_CURLY);
}
}
}
fn abi(p: &mut Parser) {
assert!(p.at(EXTERN_KW));
let abi = p.start();
p.bump();
match p.current() {
STRING | RAW_STRING => p.bump(),
_ => (),
}
abi.complete(p, ABI);
}
fn fn_item(p: &mut Parser) {
assert!(p.at(FN_KW));
p.bump();
p.expect(IDENT);
if p.at(L_PAREN) {
fn_value_parameters(p);
} else {
p.error().message("expected function arguments").emit();
}
if p.at(L_CURLY) {
p.expect(L_CURLY);
p.expect(R_CURLY);
}
fn fn_value_parameters(p: &mut Parser) {
assert!(p.at(L_PAREN));
p.bump();
p.expect(R_PAREN);
}
}