1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
|
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 = prefix_expr(p);
while let Some(m) = lhs {
match p.current() {
L_PAREN => lhs = Some(call_expr(p, m)),
_ => break,
}
}
}
fn prefix_expr(p: &mut Parser) -> Option<CompletedMarker> {
match p.current() {
AMPERSAND => Some(ref_expr(p)),
_ => atom_expr(p),
}
}
// test ref_expr
// fn foo() {
// let _ = &1;
// let _ = &mut &f();
// }
fn ref_expr(p: &mut Parser) -> CompletedMarker {
assert!(p.at(AMPERSAND));
let m = p.start();
p.bump();
p.eat(MUT_KW);
expr(p);
m.complete(p, REF_EXPR)
}
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.err_and_bump("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);
arg_list(p);
m.complete(p, CALL_EXPR)
}
fn arg_list(p: &mut Parser) {
assert!(p.at(L_PAREN));
let m = p.start();
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, ARG_LIST);
}
// 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)
}
|
