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use super::*;
pub(super) fn type_param_list(p: &mut Parser) {
if !p.at(L_ANGLE) {
return;
}
let m = p.start();
p.bump();
while !p.at(EOF) && !p.at(R_ANGLE) {
match p.current() {
LIFETIME => lifetime_param(p),
IDENT => type_param(p),
_ => p.err_and_bump("expected type parameter"),
}
if !p.at(R_ANGLE) && !p.expect(COMMA) {
break;
}
}
p.expect(R_ANGLE);
m.complete(p, TYPE_PARAM_LIST);
fn lifetime_param(p: &mut Parser) {
assert!(p.at(LIFETIME));
let m = p.start();
p.bump();
if p.at(COLON) {
lifetime_bounds(p);
}
m.complete(p, LIFETIME_PARAM);
}
fn type_param(p: &mut Parser) {
assert!(p.at(IDENT));
let m = p.start();
name(p);
if p.at(COLON) {
bounds(p);
}
// test type_param_default
// struct S<T = i32>;
if p.at(EQ) {
p.bump();
types::type_(p)
}
m.complete(p, TYPE_PARAM);
}
}
// test type_param_bounds
// struct S<T: 'a + ?Sized + (Copy)>;
pub(super) fn bounds(p: &mut Parser) {
assert!(p.at(COLON));
p.bump();
bounds_without_colon(p);
}
fn lifetime_bounds(p: &mut Parser) {
assert!(p.at(COLON));
p.bump();
while p.at(LIFETIME) {
p.bump();
if !p.eat(PLUS) {
break;
}
}
}
pub(super) fn bounds_without_colon(p: &mut Parser) {
loop {
let has_paren = p.eat(L_PAREN);
p.eat(QUESTION);
if p.at(FOR_KW) {
//TODO
}
if p.at(LIFETIME) {
p.bump();
} else if paths::is_path_start(p) {
paths::type_path(p);
} else {
break;
}
if has_paren {
p.expect(R_PAREN);
}
if !p.eat(PLUS) {
break;
}
}
}
// test where_clause
// fn foo()
// where
// 'a: 'b + 'c,
// T: Clone + Copy + 'static,
// Iterator::Item: 'a,
// {}
pub(super) fn where_clause(p: &mut Parser) {
if !p.at(WHERE_KW) {
return;
}
let m = p.start();
p.bump();
loop {
if !(paths::is_path_start(p) || p.current() == LIFETIME) {
break
}
where_predicate(p);
if p.current() != L_CURLY && p.current() != SEMI {
p.expect(COMMA);
}
}
m.complete(p, WHERE_CLAUSE);
}
fn where_predicate(p: &mut Parser) {
let m = p.start();
if p.at(LIFETIME) {
p.eat(LIFETIME);
lifetime_bounds(p)
} else {
types::path_type(p);
bounds(p);
}
m.complete(p, WHERE_PRED);
}
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