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
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
use std::{
fmt,
ops::{AddAssign, Deref},
};
use text_size::TextSize;
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub enum NodeOrToken<N, T> {
Node(N),
Token(T),
}
impl<N, T> NodeOrToken<N, T> {
pub fn into_node(self) -> Option<N> {
match self {
NodeOrToken::Node(node) => Some(node),
NodeOrToken::Token(_) => None,
}
}
pub fn into_token(self) -> Option<T> {
match self {
NodeOrToken::Node(_) => None,
NodeOrToken::Token(token) => Some(token),
}
}
pub fn as_node(&self) -> Option<&N> {
match self {
NodeOrToken::Node(node) => Some(node),
NodeOrToken::Token(_) => None,
}
}
pub fn as_token(&self) -> Option<&T> {
match self {
NodeOrToken::Node(_) => None,
NodeOrToken::Token(token) => Some(token),
}
}
}
impl<N: Deref, T: Deref> NodeOrToken<N, T> {
pub(crate) fn as_deref(&self) -> NodeOrToken<&N::Target, &T::Target> {
match self {
NodeOrToken::Node(node) => NodeOrToken::Node(&*node),
NodeOrToken::Token(token) => NodeOrToken::Token(&*token),
}
}
}
impl<N: fmt::Display, T: fmt::Display> fmt::Display for NodeOrToken<N, T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
NodeOrToken::Node(node) => fmt::Display::fmt(node, f),
NodeOrToken::Token(token) => fmt::Display::fmt(token, f),
}
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub enum Direction {
Next,
Prev,
}
#[derive(Debug, Copy, Clone)]
pub enum WalkEvent<T> {
Enter(T),
Leave(T),
}
impl<T> WalkEvent<T> {
pub fn map<F: FnOnce(T) -> U, U>(self, f: F) -> WalkEvent<U> {
match self {
WalkEvent::Enter(it) => WalkEvent::Enter(f(it)),
WalkEvent::Leave(it) => WalkEvent::Leave(f(it)),
}
}
}
#[derive(Clone, Debug)]
pub enum TokenAtOffset<T> {
None,
Single(T),
Between(T, T),
}
impl<T> TokenAtOffset<T> {
pub fn map<F: Fn(T) -> U, U>(self, f: F) -> TokenAtOffset<U> {
match self {
TokenAtOffset::None => TokenAtOffset::None,
TokenAtOffset::Single(it) => TokenAtOffset::Single(f(it)),
TokenAtOffset::Between(l, r) => TokenAtOffset::Between(f(l), f(r)),
}
}
pub fn right_biased(self) -> Option<T> {
match self {
TokenAtOffset::None => None,
TokenAtOffset::Single(node) => Some(node),
TokenAtOffset::Between(_, right) => Some(right),
}
}
pub fn left_biased(self) -> Option<T> {
match self {
TokenAtOffset::None => None,
TokenAtOffset::Single(node) => Some(node),
TokenAtOffset::Between(left, _) => Some(left),
}
}
}
impl<T> Iterator for TokenAtOffset<T> {
type Item = T;
fn next(&mut self) -> Option<T> {
match std::mem::replace(self, TokenAtOffset::None) {
TokenAtOffset::None => None,
TokenAtOffset::Single(node) => {
*self = TokenAtOffset::None;
Some(node)
}
TokenAtOffset::Between(left, right) => {
*self = TokenAtOffset::Single(right);
Some(left)
}
}
}
fn size_hint(&self) -> (usize, Option<usize>) {
match self {
TokenAtOffset::None => (0, Some(0)),
TokenAtOffset::Single(_) => (1, Some(1)),
TokenAtOffset::Between(_, _) => (2, Some(2)),
}
}
}
impl<T> ExactSizeIterator for TokenAtOffset<T> {}
macro_rules! _static_assert {
($expr:expr) => {
const _: i32 = 0 / $expr as i32;
};
}
pub(crate) use _static_assert as static_assert;
#[derive(Copy, Clone, Debug)]
pub(crate) enum Delta<T> {
Add(T),
Sub(T),
}
macro_rules! impls {
($($ty:ident)*) => {$(
impl AddAssign<Delta<$ty>> for $ty {
fn add_assign(&mut self, rhs: Delta<$ty>) {
match rhs {
Delta::Add(amt) => *self += amt,
Delta::Sub(amt) => *self -= amt,
}
}
}
)*};
}
impls!(u32 TextSize);