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
181
182
183
184
#![allow(dead_code)]
use crate::error::*;
use crate::value::*;
use fxhash::FxHashMap as HashMap;
use std::collections::hash_map::Entry;
#[derive(Debug, Eq, Default)]
pub struct EvalCtx {
symbols: HashMap<SymbolId, ValId>,
cache: HashMap<ValId, ValId>,
normalizing: bool,
}
impl EvalCtx {
pub fn new(normalizing: bool) -> EvalCtx {
EvalCtx {
normalizing,
..EvalCtx::default()
}
}
pub fn get(&self, symbol: &SymbolId) -> Option<&ValId> {
self.symbols.get(symbol)
}
pub fn is_subst(&self, symbols: &SymbolSet) -> bool {
self.symbols.keys().any(|symbol| symbols.contains(symbol))
}
pub fn is_not_subst(&self, symbols: &SymbolSet) -> bool {
self.symbols.keys().all(|symbol| !symbols.contains(symbol))
}
pub fn cached_eval(&self, value: &ValId) -> Option<&ValId> {
self.cache.get(value)
}
pub(crate) fn cache_eval(&mut self, value: ValId, eval: ValId) {
let code = eval.code();
let old = self.cache.insert(value, eval);
if let Some(old) = old {
debug_assert_eq!(old.code(), code)
}
}
pub fn flush_cache(&mut self) {
self.cache.clear()
}
pub(crate) fn def_flush(
&mut self,
symbol: SymbolId,
value: ValId,
) -> Result<(Match, bool), Error> {
let m = symbol.match_symbol(&value)?;
let change = self.def_flush_unchecked(symbol, value);
Ok((m, change))
}
pub(crate) fn def_flush_unchecked(&mut self, symbol: SymbolId, value: ValId) -> bool {
let symbol_is_value = symbol == value;
let change = match self.symbols.entry(symbol) {
Entry::Occupied(mut o) => {
if *o.get() == value {
false
} else {
o.insert(value);
true
}
}
Entry::Vacant(v) => {
if symbol_is_value {
false
} else {
v.insert(value);
true
}
}
};
if change {
self.flush_cache()
}
change
}
pub fn set_normalizing(&mut self, normalizing: bool) {
if self.normalizing != normalizing {
self.normalizing = normalizing;
self.flush_cache()
}
}
pub fn is_empty(&self) -> bool {
self.symbols.is_empty()
}
pub fn is_normalizing(&self) -> bool {
self.normalizing
}
pub fn is_null(&self) -> bool {
self.is_empty() && !self.is_normalizing()
}
pub fn added(&self, symbol: SymbolId, value: ValId) -> Result<(Match, Option<EvalCtx>), Error> {
symbol
.match_symbol(&value)
.map(|m| (m, self.added_unchecked(symbol, value)))
}
pub(crate) fn added_unchecked(&self, symbol: SymbolId, value: ValId) -> Option<EvalCtx> {
if let Some(old_value) = self.symbols.get(&symbol) {
if *old_value == value {
return None
}
} else if symbol == value {
return None
}
let mut symbols = self.symbols.clone();
symbols.insert(symbol, value);
Some(EvalCtx {
symbols,
cache: HashMap::default(),
normalizing: self.normalizing,
})
}
pub fn removed(&self, symbol: &SymbolId) -> Option<EvalCtx> {
if !self.symbols.contains_key(symbol) {
return None;
}
let mut symbols = self.symbols.clone();
symbols.remove(symbol);
Some(EvalCtx {
symbols,
cache: HashMap::default(),
normalizing: self.normalizing,
})
}
}
impl PartialEq for EvalCtx {
fn eq(&self, other: &EvalCtx) -> bool {
self.normalizing == other.normalizing && self.symbols == other.symbols
}
}
impl Clone for EvalCtx {
fn clone(&self) -> EvalCtx {
EvalCtx {
symbols: self.symbols.clone(),
cache: HashMap::default(),
normalizing: self.normalizing,
}
}
}