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
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
use super::{InferCtxt, FixupError, FixupResult};
use ty::{self, Ty, TyCtxt, TypeFoldable};
use ty::fold::TypeFolder;
pub struct OpportunisticTypeResolver<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
infcx: &'a InferCtxt<'a, 'gcx, 'tcx>,
}
impl<'a, 'gcx, 'tcx> OpportunisticTypeResolver<'a, 'gcx, 'tcx> {
pub fn new(infcx: &'a InferCtxt<'a, 'gcx, 'tcx>) -> Self {
OpportunisticTypeResolver { infcx: infcx }
}
}
impl<'a, 'gcx, 'tcx> TypeFolder<'gcx, 'tcx> for OpportunisticTypeResolver<'a, 'gcx, 'tcx> {
fn tcx<'b>(&'b self) -> TyCtxt<'b, 'gcx, 'tcx> {
self.infcx.tcx
}
fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
if !t.has_infer_types() {
t
} else {
let t0 = self.infcx.shallow_resolve(t);
t0.super_fold_with(self)
}
}
}
pub struct OpportunisticTypeAndRegionResolver<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
infcx: &'a InferCtxt<'a, 'gcx, 'tcx>,
}
impl<'a, 'gcx, 'tcx> OpportunisticTypeAndRegionResolver<'a, 'gcx, 'tcx> {
pub fn new(infcx: &'a InferCtxt<'a, 'gcx, 'tcx>) -> Self {
OpportunisticTypeAndRegionResolver { infcx: infcx }
}
}
impl<'a, 'gcx, 'tcx> TypeFolder<'gcx, 'tcx> for OpportunisticTypeAndRegionResolver<'a, 'gcx, 'tcx> {
fn tcx<'b>(&'b self) -> TyCtxt<'b, 'gcx, 'tcx> {
self.infcx.tcx
}
fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
if !t.needs_infer() {
t
} else {
let t0 = self.infcx.shallow_resolve(t);
t0.super_fold_with(self)
}
}
fn fold_region(&mut self, r: &'tcx ty::Region) -> &'tcx ty::Region {
match *r {
ty::ReVar(rid) => self.infcx.region_vars.opportunistic_resolve_var(rid),
_ => r,
}
}
}
pub fn fully_resolve<'a, 'gcx, 'tcx, T>(infcx: &InferCtxt<'a, 'gcx, 'tcx>,
value: &T) -> FixupResult<T>
where T : TypeFoldable<'tcx>
{
let mut full_resolver = FullTypeResolver { infcx: infcx, err: None };
let result = value.fold_with(&mut full_resolver);
match full_resolver.err {
None => Ok(result),
Some(e) => Err(e),
}
}
struct FullTypeResolver<'a, 'gcx: 'a+'tcx, 'tcx: 'a> {
infcx: &'a InferCtxt<'a, 'gcx, 'tcx>,
err: Option<FixupError>,
}
impl<'a, 'gcx, 'tcx> TypeFolder<'gcx, 'tcx> for FullTypeResolver<'a, 'gcx, 'tcx> {
fn tcx<'b>(&'b self) -> TyCtxt<'b, 'gcx, 'tcx> {
self.infcx.tcx
}
fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
if !t.needs_infer() {
t
} else {
let t = self.infcx.shallow_resolve(t);
match t.sty {
ty::TyInfer(ty::TyVar(vid)) => {
self.err = Some(FixupError::UnresolvedTy(vid));
self.tcx().types.err
}
ty::TyInfer(ty::IntVar(vid)) => {
self.err = Some(FixupError::UnresolvedIntTy(vid));
self.tcx().types.err
}
ty::TyInfer(ty::FloatVar(vid)) => {
self.err = Some(FixupError::UnresolvedFloatTy(vid));
self.tcx().types.err
}
ty::TyInfer(_) => {
bug!("Unexpected type in full type resolver: {:?}", t);
}
_ => {
t.super_fold_with(self)
}
}
}
}
fn fold_region(&mut self, r: &'tcx ty::Region) -> &'tcx ty::Region {
match *r {
ty::ReVar(rid) => self.infcx.region_vars.resolve_var(rid),
_ => r,
}
}
}