blob: 331c168a8faa802853e5410c45883a099d21f09f (
plain) (
blame)
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
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
|
package dotty.tools.dotc
package core
import Periods._
import Transformers._
import Names._
import Flags._
import java.lang.AssertionError
import Decorators._
import Symbols._
import Contexts._
import Denotations._
import Types._
import Referenceds.{Referenced, SymRefd, OverloadedRef}
import collection.mutable
object Symbols {
/**
* A SymRef is a period-dependent reference to a denotation.
* Given a period, its `deref` method resolves to a Symbol.
*/
abstract class Symbol {
def overriddenSymbol(inclass: ClassSymbol)(implicit ctx: Context): Symbol =
if (owner isSubClass inclass) ???
else NoSymbol
def isProtected: Boolean = ???
def isStable: Boolean = ???
def accessBoundary: ClassSymbol = ???
def isContainedIn(boundary: ClassSymbol) = ???
def baseClasses: List[ClassSymbol] = ???
def exists = true
def orElse(that: => Symbol) = if (exists) this else that
/** A isAbove B iff A can always be used instead of B
*/
def isAbove(that: Symbol)(implicit ctx: Context): Boolean =
(that.owner isSubClass this.owner) &&
(this isAsAccessible that)
/** A isBelow B iff the reference A & B can always be simplified to A
*/
def isBelow(that: Symbol)(implicit ctx: Context): Boolean =
(this.owner isSubClass that.owner) ||
(this isAsAccessible that)
def isAsAccessible(that: Symbol)(implicit ctx: Context): Boolean =
!this.isProtected && !that.isProtected && // protected members are incomparable
(that.accessBoundary isContainedIn this.accessBoundary) &&
this.isStable || !that.isStable
/** Set the denotation of this symbol.
*/
def setDenotation(denot: Denotation) =
lastDenot = denot
/** The last denotation of this symbol */
protected[this] var lastDenot: Denotation = null
/** Load denotation of this symbol */
protected def loadDenot(implicit ctx: Context): Denotation
/** The denotation of this symbol
*/
def deref(implicit ctx: Context): Denotation = {
val denot = lastDenot
if (denot == null) loadDenot
else {
val currentPeriod = ctx.period
val valid = denot.validFor
if (valid contains currentPeriod) denot
else if (valid.runId != currentPeriod.runId) reloadDenot
else denot.current.asDenotation
}
}
/**
* Get loaded denotation if lastDenot points to a denotation from
* a different run. !!! needed?
*/
private def reloadDenot(implicit ctx: Context): Denotation = {
val initDenot = lastDenot.initial.asDenotation
val newSym: Symbol =
ctx.atPhase(FirstPhaseId) { implicit ctx =>
initDenot.owner.info.decl(initDenot.name)
.atSignature(deref.signature).symbol
}
if (newSym eq this) { // no change, change validity
var d = initDenot
do {
d.validFor = Period(ctx.runId, d.validFor.firstPhaseId, d.validFor.lastPhaseId)
d = d.nextInRun.asDenotation
} while (d ne initDenot)
}
newSym.deref
}
def isType: Boolean
def isTerm = !isType
// forwarders for sym methods
def owner(implicit ctx: Context): Symbol = deref.owner
def name(implicit ctx: Context): Name = deref.name
def flags(implicit ctx: Context): FlagSet = deref.flags
def info(implicit ctx: Context): Type = deref.info
def prefix(implicit ctx: Context) = owner.thisType
def allOverriddenSymbols: Iterator[Symbol] = ???
def isAsAccessibleAs(other: Symbol): Boolean = ???
def isAccessibleFrom(pre: Type)(implicit ctx: Context): Boolean = ???
def locationString: String = ???
def locatedFullString: String = ???
def defString: String = ???
def typeParams: List[TypeSymbol] = ???
def unsafeTypeParams: List[TypeSymbol] = ???
def thisType: Type = ???
def isStaticMono = isStatic && typeParams.isEmpty
def isPackageClass: Boolean = ???
def isRoot: Boolean = ???
def moduleClass: Symbol = ???
def cloneSymbol: Symbol = ???
def asTerm: TermSymbol = ???
def asType: TypeSymbol = ???
def asClass: ClassSymbol = ???
def isStatic: Boolean = ???
def isTypeParameter: Boolean = ???
def isOverridable: Boolean = ???
def isCovariant: Boolean = ???
def isContravariant: Boolean = ???
def isSkolem: Boolean = ???
def isDeferred: Boolean = ???
def isConcrete = !isDeferred
def isJava: Boolean = ???
def isSubClass(that: Symbol): Boolean = ???
def isNonBottomSubClass(that: Symbol): Boolean = ???
def isProperSubClass(that: Symbol): Boolean =
(this ne that) && (this isSubClass that)
def isAbstractType: Boolean = ???
def newAbstractType(name: TypeName, info: TypeBounds): TypeSymbol = ???
def newAbstractTerm(name: TermName, tpe: Type): TypeSymbol = ???
def isClass: Boolean = false
def isMethod(implicit ctx: Context): Boolean = deref.isMethod
def hasFlag(required: FlagSet)(implicit ctx: Context): Boolean = (flags & required) != Flags.Empty
def hasAllFlags(required: FlagSet)(implicit ctx: Context): Boolean = (flags & required) == flags
def containsNull(implicit ctx: Context): Boolean =
isClass && !(isSubClass(defn.AnyValClass))
}
abstract class TermSymbol extends Symbol {
def name: TermName
def isType = true
}
trait RefinementSymbol extends Symbol {
override def deref(implicit ctx: Context) = lastDenot
}
abstract class RefinementTermSymbol extends TermSymbol with RefinementSymbol
abstract class RefinementTypeSymbol extends TypeSymbol with RefinementSymbol
abstract class TypeSymbol extends Symbol {
def name: TypeName
def isType = false
def variance: Int = ???
def typeConstructor(implicit ctx: Context): Type = ???
def typeTemplate(implicit ctx: Context): Type = ???
}
abstract class ClassSymbol extends TypeSymbol {
override def isClass = true
private var superIdHint: Int = -1
override def deref(implicit ctx: Context): ClassDenotation =
super.deref.asInstanceOf[ClassDenotation]
def typeOfThis(implicit ctx: Context): Type = ???
override def typeConstructor(implicit ctx: Context): Type = deref.typeConstructor
override def typeTemplate(implicit ctx: Context): Type = deref.typeTemplate
/** The unique, densely packed identifier of this class symbol. Should be called
* only if class is a super class of some other class.
*/
def superId(implicit ctx: Context): Int = {
val hint = superIdHint
val rctx = ctx.root
if (hint >= 0 && hint <= rctx.lastSuperId && (rctx.classOfId(hint) eq this)) hint
else {
val id = rctx.superIdOfClass get this match {
case Some(id) =>
id
case None =>
val id = rctx.nextSuperId
rctx.superIdOfClass(this) = id
rctx.classOfId(id) = this
id
}
superIdHint = id
id
}
}
}
object NoSymbol extends Symbol {
def loadDenot(implicit ctx: Context): Denotation = NoDenotation
override def exists = false
def isType = false
}
implicit def defn(implicit ctx: Context): Definitions = ctx.root.definitions
}
|