rust/src/parser/event_parser/grammar/attributes.rs

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2018-01-07 19:46:10 +01:00
use super::*;
pub(super) fn inner_attributes(p: &mut Parser) {
many(p, |p| attribute(p, true))
}
pub(super) fn outer_attributes(_: &mut Parser) {
}
fn attribute(p: &mut Parser, inner: bool) -> bool {
let attr_start = inner && p.lookahead(&[POUND, EXCL, L_BRACK])
|| !inner && p.lookahead(&[POUND, L_BRACK]);
if !attr_start {
return false;
}
node(p, ATTR, |p| {
p.bump_n(if inner { 3 } else { 2 });
meta_item(p) && p.expect(R_BRACK);
});
true
}
fn meta_item(p: &mut Parser) -> bool {
node_if(p, IDENT, META_ITEM, |p| {
if p.eat(EQ) {
if !expressions::literal(p) {
p.error()
.message("expected literal")
.emit();
}
} else if p.eat(L_PAREN) {
comma_list(p, R_PAREN, meta_item_inner);
p.expect(R_PAREN);
}
})
}
fn meta_item_inner(p: &mut Parser) -> bool {
meta_item(p) || expressions::literal(p)
}