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use super::*;
// test expr_literals
// fn foo() {
// let _ = true;
// let _ = false;
// let _ = 1;
// let _ = 2.0;
// let _ = b'a';
// let _ = 'b';
// let _ = "c";
// let _ = r"d";
// let _ = b"e";
// let _ = br"f";
// }
pub(super) fn literal(p: &mut Parser) -> Option<CompletedMarker> {
match p.current() {
TRUE_KW | FALSE_KW | INT_NUMBER | FLOAT_NUMBER | BYTE | CHAR | STRING | RAW_STRING
| BYTE_STRING | RAW_BYTE_STRING => {
let m = p.start();
p.bump();
Some(m.complete(p, LITERAL))
}
_ => None,
}
}
pub(super) fn expr(p: &mut Parser) {
let mut lhs = atom_expr(p);
while let Some(m) = lhs {
match p.current() {
L_PAREN => lhs = Some(call_expr(p, m)),
_ => break,
}
}
}
fn atom_expr(p: &mut Parser) -> Option<CompletedMarker> {
match literal(p) {
Some(m) => return Some(m),
None => (),
}
if paths::is_path_start(p) {
return Some(path_expr(p));
}
match p.current() {
L_PAREN => Some(tuple_expr(p)),
_ => {
p.error("expected expression");
None
}
}
}
fn tuple_expr(p: &mut Parser) -> CompletedMarker {
assert!(p.at(L_PAREN));
let m = p.start();
p.expect(L_PAREN);
p.expect(R_PAREN);
m.complete(p, TUPLE_EXPR)
}
// test call_expr
// fn foo() {
// let _ = f();
// let _ = f()(1)(1, 2,);
// }
fn call_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker {
assert!(p.at(L_PAREN));
let m = lhs.precede(p);
p.bump();
while !p.at(R_PAREN) && !p.at(EOF) {
expr(p);
if !p.at(R_PAREN) && !p.expect(COMMA) {
break;
}
}
p.eat(R_PAREN);
m.complete(p, CALL_EXPR)
}
// test path_expr
// fn foo() {
// let _ = a;
// let _ = a::b;
// let _ = ::a::<b>;
// }
fn path_expr(p: &mut Parser) -> CompletedMarker {
assert!(paths::is_path_start(p));
let m = p.start();
paths::expr_path(p);
m.complete(p, PATH_EXPR)
}
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