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|
use super::*;
mod consts;
mod structs;
mod traits;
mod use_item;
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("expected `fn` or `{`");
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
}
},
UNSAFE_KW => {
p.bump();
let la = p.nth(1);
match p.current() {
// test unsafe_trait
// unsafe trait T {}
TRAIT_KW => {
traits::trait_item(p);
TRAIT_ITEM
}
// test unsafe_auto_trait
// unsafe auto trait T {}
IDENT if p.at_contextual_kw("auto") && la == TRAIT_KW => {
p.bump_remap(AUTO_KW);
traits::trait_item(p);
TRAIT_ITEM
}
// test unsafe_impl
// unsafe impl Foo {}
IMPL_KW => {
traits::impl_item(p);
IMPL_ITEM
}
// test unsafe_default_impl
// unsafe default impl Foo {}
IDENT if p.at_contextual_kw("default") && la == IMPL_KW => {
p.bump_remap(DEFAULT_KW);
traits::impl_item(p);
IMPL_ITEM
}
// test unsafe_extern_fn
// unsafe extern "C" fn foo() {}
EXTERN_KW => {
abi(p);
if !p.at(FN_KW) {
item.abandon(p);
p.error("expected function");
return;
}
fn_item(p);
FN_ITEM
}
// test unsafe_fn
// unsafe fn foo() {}
FN_KW => {
fn_item(p);
FN_ITEM
}
t => {
item.abandon(p);
let message = "expected `trait`, `impl` or `fn`";
// test unsafe_block_in_mod
// fn foo(){} unsafe { } fn bar(){}
if t == L_CURLY {
error_block(p, message);
} else {
p.error(message);
}
return;
}
}
}
FN_KW => {
fn_item(p);
FN_ITEM
}
TYPE_KW => {
type_item(p);
TYPE_ITEM
}
MOD_KW => {
mod_item(p);
MOD_ITEM
}
STRUCT_KW => {
structs::struct_item(p);
STRUCT_ITEM
}
ENUM_KW => {
structs::enum_item(p);
ENUM_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();
name(p);
alias(p);
p.expect(SEMI);
}
fn extern_block(p: &mut Parser) {
assert!(p.at(L_CURLY));
p.bump();
p.expect(R_CURLY);
}
fn fn_item(p: &mut Parser) {
assert!(p.at(FN_KW));
p.bump();
name(p);
if p.at(L_PAREN) {
fn_value_parameters(p);
} else {
p.error("expected function arguments");
}
// test fn_item_ret_type
// fn foo() {}
// fn bar() -> () {}
fn_ret_type(p);
block(p);
// test block
// fn a() {}
// fn b() { let _ = 1; }
// fn c() { 1; 2; }
// fn d() { 1; 2 }
fn block(p: &mut Parser) {
if !p.at(L_CURLY) {
p.error("expected block");
}
let m = p.start();
p.bump();
while !p.at(EOF) && !p.at(R_CURLY) {
match p.current() {
LET_KW => let_stmt(p),
_ => {
let expr_stmt = p.start();
expressions::expr(p);
if p.eat(SEMI) {
expr_stmt.complete(p, EXPR_STMT);
if p.at(R_CURLY) {
break;
}
} else {
expr_stmt.abandon(p);
}
}
}
}
p.expect(R_CURLY);
m.complete(p, BLOCK);
}
fn let_stmt(p: &mut Parser) {
assert!(p.at(LET_KW));
let m = p.start();
p.bump();
patterns::pattern(p);
p.expect(EQ);
expressions::expr(p);
p.expect(SEMI);
m.complete(p, LET_STMT);
}
}
// test type_item
// type Foo = Bar;
fn type_item(p: &mut Parser) {
assert!(p.at(TYPE_KW));
p.bump();
name(p);
// test type_item_type_params
// type Result<T> = ();
type_params::list(p);
// test type_item_where_clause
// type Foo where Foo: Copy = ();
type_params::where_clause(p);
p.expect(EQ);
types::type_(p);
p.expect(SEMI);
}
fn mod_item(p: &mut Parser) {
assert!(p.at(MOD_KW));
p.bump();
name(p);
if !p.eat(SEMI) {
if p.expect(L_CURLY) {
mod_contents(p, true);
p.expect(R_CURLY);
}
}
}
|
