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Compiler for the Scala Programming Language
/* NSC -- new Scala compiler
* Copyright 2005-2013 LAMP/EPFL
* @author Martin Odersky
*/
package scala.reflect
package internal
import scala.collection.{ mutable, immutable }
import scala.collection.mutable.ListBuffer
import util.Statistics
import Flags._
import scala.annotation.tailrec
import scala.reflect.io.AbstractFile
trait Symbols extends api.Symbols { self: SymbolTable =>
import definitions._
import SymbolsStats._
protected var ids = 0
val emptySymbolArray = new Array[Symbol](0)
protected def nextId() = { ids += 1; ids }
/** Used for deciding in the IDE whether we can interrupt the compiler */
//protected var activeLocks = 0
/** Used for debugging only */
//protected var lockedSyms = scala.collection.immutable.Set[Symbol]()
/** Used to keep track of the recursion depth on locked symbols */
private var recursionTable = immutable.Map.empty[Symbol, Int]
private var nextexid = 0
protected def freshExistentialName(suffix: String) = {
nextexid += 1
newTypeName("_" + nextexid + suffix)
}
// Set the fields which point companions at one another. Returns the module.
def connectModuleToClass(m: ModuleSymbol, moduleClass: ClassSymbol): ModuleSymbol = {
moduleClass.sourceModule = m
m setModuleClass moduleClass
m
}
/** Create a new free term. Its owner is NoSymbol.
*/
def newFreeTermSymbol(name: TermName, value: => Any, flags: Long = 0L, origin: String): FreeTermSymbol =
new FreeTermSymbol(name, value, origin) initFlags flags
/** Create a new free type. Its owner is NoSymbol.
*/
def newFreeTypeSymbol(name: TypeName, flags: Long = 0L, origin: String): FreeTypeSymbol =
new FreeTypeSymbol(name, origin) initFlags flags
/** Determines whether the given information request should trigger the given symbol's completer.
* See comments to `Symbol.needsInitialize` for details.
*/
protected def shouldTriggerCompleter(symbol: Symbol, completer: Type, isFlagRelated: Boolean, mask: Long) =
completer match {
case null => false
case _: FlagAgnosticCompleter => !isFlagRelated
case _ => abort(s"unsupported completer: $completer of class ${if (completer != null) completer.getClass else null} for symbol ${symbol.fullName}")
}
/** The original owner of a class. Used by the backend to generate
* EnclosingMethod attributes.
*/
val originalOwner = perRunCaches.newMap[Symbol, Symbol]()
abstract class SymbolContextApiImpl extends SymbolContextApi {
this: Symbol =>
def isExistential: Boolean = this.isExistentiallyBound
def isParamWithDefault: Boolean = this.hasDefault
def isByNameParam: Boolean = this.isValueParameter && (this hasFlag BYNAMEPARAM)
def isImplementationArtifact: Boolean = (this hasFlag BRIDGE) || (this hasFlag VBRIDGE) || (this hasFlag ARTIFACT)
def isJava: Boolean = isJavaDefined
def isVal: Boolean = isTerm && !isModule && !isMethod && !isMutable
def isVar: Boolean = isTerm && !isModule && !isMethod && !isLazy && isMutable
def newNestedSymbol(name: Name, pos: Position, newFlags: Long, isClass: Boolean): Symbol = name match {
case n: TermName => newTermSymbol(n, pos, newFlags)
case n: TypeName => if (isClass) newClassSymbol(n, pos, newFlags) else newNonClassSymbol(n, pos, newFlags)
}
def knownDirectSubclasses = {
if (!isCompilerUniverse && needsInitialize(isFlagRelated = false, mask = 0)) initialize
children
}
def baseClasses = info.baseClasses
def module = sourceModule
def thisPrefix: Type = thisType
def selfType: Type = typeOfThis
def typeSignature: Type = { fullyInitializeSymbol(this); info }
def typeSignatureIn(site: Type): Type = { fullyInitializeSymbol(this); site memberInfo this }
def toType: Type = tpe
def toTypeIn(site: Type): Type = site.memberType(this)
def toTypeConstructor: Type = typeConstructor
def setTypeSignature(tpe: Type): this.type = { setInfo(tpe); this }
def setAnnotations(annots: AnnotationInfo*): this.type = { setAnnotations(annots.toList); this }
def getter: Symbol = getter(owner)
def setter: Symbol = setter(owner)
}
/** The class for all symbols */
abstract class Symbol protected[Symbols] (initOwner: Symbol, initPos: Position, initName: Name)
extends SymbolContextApiImpl
with HasFlags
with Annotatable[Symbol]
with Attachable {
type AccessBoundaryType = Symbol
type AnnotationType = AnnotationInfo
// TODO - don't allow names to be renamed in this unstructured a fashion.
// Rename as little as possible. Enforce invariants on all renames.
type TypeOfClonedSymbol >: Null <: Symbol { type NameType = Symbol.this.NameType }
// Abstract here so TypeSymbol and TermSymbol can have a private[this] field
// with the proper specific type.
def rawname: NameType
def name: NameType
def name_=(n: Name): Unit = {
if (shouldLogAtThisPhase) {
val msg = s"Renaming $fullLocationString to $n"
if (isSpecialized) debuglog(msg) else log(msg)
}
}
def asNameType(n: Name): NameType
private[this] var _rawowner = initOwner // Syncnote: need not be protected, as only assignment happens in owner_=, which is not exposed to api
private[this] var _rawflags: Long = _
def rawowner = _rawowner
def rawflags = _rawflags
rawatt = initPos
val id = nextId() // identity displayed when -uniqid
//assert(id != 3390, initName)
private[this] var _validTo: Period = NoPeriod
if (traceSymbolActivity)
traceSymbols.recordNewSymbol(this)
def validTo = _validTo
def validTo_=(x: Period) { _validTo = x}
def setName(name: Name): this.type = { this.name = asNameType(name) ; this }
// Update the surrounding scopes
protected[this] def changeNameInOwners(name: Name) {
if (owner.isClass) {
var ifs = owner.infos
while (ifs != null) {
ifs.info.decls.rehash(this, name)
ifs = ifs.prev
}
}
}
def rawFlagString(mask: Long): String = calculateFlagString(rawflags & mask)
def rawFlagString: String = rawFlagString(flagMask)
def debugFlagString: String = flagString(AllFlags)
/** String representation of symbol's variance */
def varianceString: String =
if (variance == 1) "+"
else if (variance == -1) "-"
else ""
override def flagMask =
if (settings.debug.value && !isAbstractType) AllFlags
else if (owner.isRefinementClass) ExplicitFlags & ~OVERRIDE
else ExplicitFlags
// make the error message more googlable
def flagsExplanationString =
if (isGADTSkolem) " (this is a GADT skolem)"
else ""
def shortSymbolClass = getClass.getName.split('.').last.stripPrefix("Symbols$")
def symbolCreationString: String = (
"%s%25s | %-40s | %s".format(
if (settings.uniqid.value) "%06d | ".format(id) else "",
shortSymbolClass,
name.decode + " in " + owner,
rawFlagString
)
)
// ------ creators -------------------------------------------------------------------
final def newValue(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): TermSymbol =
newTermSymbol(name, pos, newFlags)
final def newVariable(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): TermSymbol =
newTermSymbol(name, pos, MUTABLE | newFlags)
final def newValueParameter(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): TermSymbol =
newTermSymbol(name, pos, PARAM | newFlags)
/** Create local dummy for template (owner of local blocks) */
final def newLocalDummy(pos: Position): TermSymbol =
newTermSymbol(nme.localDummyName(this), pos) setInfo NoType
final def newMethod(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): MethodSymbol =
createMethodSymbol(name, pos, METHOD | newFlags)
final def newMethodSymbol(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): MethodSymbol =
createMethodSymbol(name, pos, METHOD | newFlags)
final def newLabel(name: TermName, pos: Position = NoPosition): MethodSymbol =
newMethod(name, pos, LABEL)
/** Propagates ConstrFlags (JAVA, specifically) from owner to constructor. */
final def newConstructor(pos: Position, newFlags: Long = 0L): MethodSymbol =
newMethod(nme.CONSTRUCTOR, pos, getFlag(ConstrFlags) | newFlags)
/** Static constructor with info set. */
def newStaticConstructor(pos: Position): MethodSymbol =
newConstructor(pos, STATIC) setInfo UnitClass.tpe
/** Instance constructor with info set. */
def newClassConstructor(pos: Position): MethodSymbol =
newConstructor(pos) setInfo MethodType(Nil, this.tpe)
def newLinkedModule(clazz: Symbol, newFlags: Long = 0L): ModuleSymbol = {
val m = newModuleSymbol(clazz.name.toTermName, clazz.pos, MODULE | newFlags)
connectModuleToClass(m, clazz.asInstanceOf[ClassSymbol])
}
final def newModule(name: TermName, pos: Position = NoPosition, newFlags0: Long = 0L): ModuleSymbol = {
val newFlags = newFlags0 | MODULE
val m = newModuleSymbol(name, pos, newFlags)
val clazz = newModuleClass(name.toTypeName, pos, newFlags & ModuleToClassFlags)
connectModuleToClass(m, clazz)
}
final def newPackage(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): ModuleSymbol = {
assert(name == nme.ROOT || isPackageClass, this)
newModule(name, pos, PackageFlags | newFlags)
}
final def newThisSym(name: TermName = nme.this_, pos: Position = NoPosition): TermSymbol =
newTermSymbol(name, pos, SYNTHETIC)
final def newImport(pos: Position): TermSymbol =
newTermSymbol(nme.IMPORT, pos)
final def newModuleSymbol(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): ModuleSymbol =
newTermSymbol(name, pos, newFlags).asInstanceOf[ModuleSymbol]
final def newModuleAndClassSymbol(name: Name, pos: Position, flags0: FlagSet): (ModuleSymbol, ClassSymbol) = {
val flags = flags0 | MODULE
val m = newModuleSymbol(name, pos, flags)
val c = newModuleClass(name.toTypeName, pos, flags & ModuleToClassFlags)
connectModuleToClass(m, c)
(m, c)
}
final def newPackageSymbol(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): ModuleSymbol =
newTermSymbol(name, pos, newFlags).asInstanceOf[ModuleSymbol]
final def newModuleClassSymbol(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): ModuleClassSymbol =
newClassSymbol(name, pos, newFlags).asInstanceOf[ModuleClassSymbol]
final def newTypeSkolemSymbol(name: TypeName, origin: AnyRef, pos: Position = NoPosition, newFlags: Long = 0L): TypeSkolem =
createTypeSkolemSymbol(name, origin, pos, newFlags)
/** @param pre type relative to which alternatives are seen.
* for instance:
* class C[T] {
* def m(x: T): T
* def m'(): T
* }
* val v: C[Int]
*
* Then v.m has symbol TermSymbol(flags = {OVERLOADED},
* tpe = OverloadedType(C[Int], List(m, m')))
* You recover the type of m doing a
*
* m.tpe.asSeenFrom(pre, C) (generally, owner of m, which is C here).
*
* or:
*
* pre.memberType(m)
*/
final def newOverloaded(pre: Type, alternatives: List[Symbol]): TermSymbol = (
newTermSymbol(alternatives.head.name.toTermName, alternatives.head.pos, OVERLOADED)
setInfo OverloadedType(pre, alternatives)
)
final def newErrorValue(name: TermName): TermSymbol =
newTermSymbol(name, pos, SYNTHETIC | IS_ERROR) setInfo ErrorType
/** Symbol of a type definition type T = ...
*/
final def newAliasType(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): AliasTypeSymbol =
createAliasTypeSymbol(name, pos, newFlags)
/** Symbol of an abstract type type T >: ... <: ...
*/
final def newAbstractType(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): AbstractTypeSymbol =
createAbstractTypeSymbol(name, pos, DEFERRED | newFlags)
/** Symbol of a type parameter
*/
final def newTypeParameter(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): TypeSymbol =
newAbstractType(name, pos, PARAM | newFlags)
// is defined in SymbolCreations
// final def newTypeSymbol(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): TypeSymbol =
// (if ((newFlags & DEFERRED) != 0) new AbstractTypeSymbol(this, pos, name)
// else new AbstractTypeSymbol(this, pos, name)) setFlag newFlags
/** Symbol of an existential type T forSome { ... }
*/
final def newExistential(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): TypeSymbol =
newAbstractType(name, pos, EXISTENTIAL | newFlags)
private def freshNamer: () => TermName = {
var cnt = 0
() => { cnt += 1; nme.syntheticParamName(cnt) }
}
/** Synthetic value parameters when parameter symbols are not available
*/
final def newSyntheticValueParamss(argtypess: List[List[Type]]): List[List[TermSymbol]] =
argtypess map (xs => newSyntheticValueParams(xs, freshNamer))
/** Synthetic value parameters when parameter symbols are not available.
* Calling this method multiple times will re-use the same parameter names.
*/
final def newSyntheticValueParams(argtypes: List[Type]): List[TermSymbol] =
newSyntheticValueParams(argtypes, freshNamer)
final def newSyntheticValueParams(argtypes: List[Type], freshName: () => TermName): List[TermSymbol] =
argtypes map (tp => newSyntheticValueParam(tp, freshName()))
/** Synthetic value parameter when parameter symbol is not available.
* Calling this method multiple times will re-use the same parameter name.
*/
final def newSyntheticValueParam(argtype: Type, name: TermName = nme.syntheticParamName(1)): TermSymbol =
newValueParameter(name, owner.pos.focus, SYNTHETIC) setInfo argtype
def newSyntheticTypeParam(): TypeSymbol = newSyntheticTypeParam("T0", 0L)
def newSyntheticTypeParam(name: String, newFlags: Long): TypeSymbol = newTypeParameter(newTypeName(name), NoPosition, newFlags) setInfo TypeBounds.empty
def newSyntheticTypeParams(num: Int): List[TypeSymbol] = (0 until num).toList map (n => newSyntheticTypeParam("T" + n, 0L))
/** Create a new existential type skolem with this symbol its owner,
* based on the given symbol and origin.
*/
def newExistentialSkolem(basis: Symbol, origin: AnyRef): TypeSkolem = {
val skolem = newTypeSkolemSymbol(basis.name.toTypeName, origin, basis.pos, (basis.flags | EXISTENTIAL) & ~PARAM)
skolem setInfo (basis.info cloneInfo skolem)
}
// don't test directly -- use isGADTSkolem
// used to single out a gadt skolem symbol in deskolemizeGADT
// gadtskolems are created in adaptConstrPattern and removed at the end of typedCase
final protected[Symbols] def GADT_SKOLEM_FLAGS = CASEACCESSOR | SYNTHETIC
// flags set up to maintain TypeSkolem's invariant: origin.isInstanceOf[Symbol] == !hasFlag(EXISTENTIAL)
// GADT_SKOLEM_FLAGS (== CASEACCESSOR | SYNTHETIC) used to single this symbol out in deskolemizeGADT
// TODO: it would be better to allocate a new bit in the flag long for GADTSkolem rather than OR'ing together CASEACCESSOR | SYNTHETIC
def newGADTSkolem(name: TypeName, origin: Symbol, info: Type): TypeSkolem =
newTypeSkolemSymbol(name, origin, origin.pos, origin.flags & ~(EXISTENTIAL | PARAM) | GADT_SKOLEM_FLAGS) setInfo info
final def freshExistential(suffix: String): TypeSymbol =
newExistential(freshExistentialName(suffix), pos)
/** Type skolems are type parameters ''seen from the inside''
* Assuming a polymorphic method m[T], its type is a PolyType which has a TypeParameter
* with name `T` in its typeParams list. While type checking the parameters, result type and
* body of the method, there's a local copy of `T` which is a TypeSkolem.
*/
final def newTypeSkolem: TypeSkolem =
owner.newTypeSkolemSymbol(name.toTypeName, this, pos, flags)
final def newClass(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): ClassSymbol =
newClassSymbol(name, pos, newFlags)
/** A new class with its info set to a ClassInfoType with given scope and parents. */
def newClassWithInfo(name: TypeName, parents: List[Type], scope: Scope, pos: Position = NoPosition, newFlags: Long = 0L): ClassSymbol = {
val clazz = newClass(name, pos, newFlags)
clazz setInfo ClassInfoType(parents, scope, clazz)
}
final def newErrorClass(name: TypeName): ClassSymbol =
newClassWithInfo(name, Nil, new ErrorScope(this), pos, SYNTHETIC | IS_ERROR)
final def newModuleClass(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): ModuleClassSymbol =
newModuleClassSymbol(name, pos, newFlags | MODULE)
final def newAnonymousFunctionClass(pos: Position = NoPosition, newFlags: Long = 0L): ClassSymbol =
newClassSymbol(tpnme.ANON_FUN_NAME, pos, FINAL | SYNTHETIC | newFlags)
final def newAnonymousFunctionValue(pos: Position, newFlags: Long = 0L): TermSymbol =
newTermSymbol(nme.ANON_FUN_NAME, pos, SYNTHETIC | newFlags) setInfo NoType
def newImplClass(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): ClassSymbol = {
newClassSymbol(name, pos, newFlags | IMPLCLASS)
}
/** Refinement types P { val x: String; type T <: Number }
* also have symbols, they are refinementClasses
*/
final def newRefinementClass(pos: Position): RefinementClassSymbol =
createRefinementClassSymbol(pos, 0L)
/** Create a new getter for current symbol (which must be a field)
*/
final def newGetter: MethodSymbol = (
owner.newMethod(nme.getterName(name.toTermName), NoPosition, getterFlags(flags))
setPrivateWithin privateWithin
setInfo MethodType(Nil, tpe)
)
final def newErrorSymbol(name: Name): Symbol = name match {
case x: TypeName => newErrorClass(x)
case x: TermName => newErrorValue(x)
}
/** Creates a placeholder symbol for when a name is encountered during
* unpickling for which there is no corresponding classfile. This defers
* failure to the point when that name is used for something, which is
* often to the point of never.
*/
def newStubSymbol(name: Name, missingMessage: String): Symbol = name match {
case n: TypeName => new StubClassSymbol(this, n, missingMessage)
case _ => new StubTermSymbol(this, name.toTermName, missingMessage)
}
@deprecated("Use the other signature", "2.10.0")
def newClass(pos: Position, name: TypeName): Symbol = newClass(name, pos)
@deprecated("Use the other signature", "2.10.0")
def newModuleClass(pos: Position, name: TypeName): Symbol = newModuleClass(name, pos)
@deprecated("Use the other signature", "2.10.0")
def newLabel(pos: Position, name: TermName): MethodSymbol = newLabel(name, pos)
@deprecated("Use the other signature", "2.10.0")
def newValue(pos: Position, name: TermName): TermSymbol = newTermSymbol(name, pos)
@deprecated("Use the other signature", "2.10.0")
def newAliasType(pos: Position, name: TypeName): Symbol = newAliasType(name, pos)
@deprecated("Use the other signature", "2.10.0")
def newAbstractType(pos: Position, name: TypeName): Symbol = newAbstractType(name, pos)
@deprecated("Use the other signature", "2.10.0")
def newExistential(pos: Position, name: TypeName): Symbol = newExistential(name, pos)
@deprecated("Use the other signature", "2.10.0")
def newMethod(pos: Position, name: TermName): MethodSymbol = newMethod(name, pos)
// ----- locking and unlocking ------------------------------------------------------
// True if the symbol is unlocked.
// True if the symbol is locked but still below the allowed recursion depth.
// False otherwise
private[scala] def lockOK: Boolean = {
((_rawflags & LOCKED) == 0L) ||
((settings.Yrecursion.value != 0) &&
(recursionTable get this match {
case Some(n) => (n <= settings.Yrecursion.value)
case None => true }))
}
// Lock a symbol, using the handler if the recursion depth becomes too great.
private[scala] def lock(handler: => Unit): Boolean = {
if ((_rawflags & LOCKED) != 0L) {
if (settings.Yrecursion.value != 0) {
recursionTable get this match {
case Some(n) =>
if (n > settings.Yrecursion.value) {
handler
false
} else {
recursionTable += (this -> (n + 1))
true
}
case None =>
recursionTable += (this -> 1)
true
}
} else { handler; false }
} else {
_rawflags |= LOCKED
true
// activeLocks += 1
// lockedSyms += this
}
}
// Unlock a symbol
private[scala] def unlock() = {
if ((_rawflags & LOCKED) != 0L) {
// activeLocks -= 1
// lockedSyms -= this
_rawflags &= ~LOCKED
if (settings.Yrecursion.value != 0)
recursionTable -= this
}
}
// ----- tests ----------------------------------------------------------------------
def isAliasType = false
def isAbstractType = false
def isSkolem = false
/** A Type, but not a Class. */
def isNonClassType = false
/** The bottom classes are Nothing and Null, found in Definitions. */
def isBottomClass = false
/** These are all tests for varieties of ClassSymbol, which has these subclasses:
* - ModuleClassSymbol
* - RefinementClassSymbol
* - PackageClassSymbol (extends ModuleClassSymbol)
*/
def isAbstractClass = false
def isAnonOrRefinementClass = false
def isAnonymousClass = false
def isCaseClass = false
def isConcreteClass = false
def isImplClass = false // the implementation class of a trait
def isJavaInterface = false
def isNumericValueClass = false
def isPrimitiveValueClass = false
def isRefinementClass = false
override def isTrait = false
/** Qualities of Types, always false for TermSymbols.
*/
def isContravariant = false
def isCovariant = false
def isExistentialQuantified = false
def isExistentialSkolem = false
def isExistentiallyBound = false
def isGADTSkolem = false
def isTypeParameter = false
def isTypeParameterOrSkolem = false
def isTypeSkolem = false
def isTypeMacro = false
def isInvariant = !isCovariant && !isContravariant
/** Qualities of Terms, always false for TypeSymbols.
*/
def isAccessor = false
def isBridge = false
def isCapturedVariable = false
def isClassConstructor = false
def isConstructor = false
def isEarlyInitialized = false
def isGetter = false
def isLocalDummy = false
def isMixinConstructor = false
def isOverloaded = false
def isSetter = false
def isSetterParameter = false
def isValue = false
def isValueParameter = false
def isVariable = false
override def hasDefault = false
def isTermMacro = false
/** Qualities of MethodSymbols, always false for TypeSymbols
* and other TermSymbols.
*/
def isCaseAccessorMethod = false
def isLiftedMethod = false
def isSourceMethod = false
def isVarargsMethod = false
override def isLabel = false
/** Package/package object tests */
def isPackageClass = false
def isPackageObject = false
def isPackageObjectClass = false
def isPackageObjectOrClass = isPackageObject || isPackageObjectClass
def isModuleOrModuleClass = isModule || isModuleClass
/** Overridden in custom objects in Definitions */
def isRoot = false
def isRootPackage = false
def isRootSymbol = false // RootPackage and RootClass. TODO: also NoSymbol.
def isEmptyPackage = false
def isEmptyPackageClass = false
/** Is this symbol an effective root for fullname string?
*/
def isEffectiveRoot = false
final def isLazyAccessor = isLazy && lazyAccessor != NoSymbol
final def isOverridableMember = !(isClass || isEffectivelyFinal) && (this ne NoSymbol) && owner.isClass
/** Does this symbol denote a wrapper created by the repl? */
final def isInterpreterWrapper = (
(this hasFlag MODULE)
&& owner.isPackageClass
&& nme.isReplWrapperName(name)
)
final def getFlag(mask: Long): Long = {
if (!isCompilerUniverse && needsInitialize(isFlagRelated = true, mask = mask)) initialize
flags & mask
}
/** Does symbol have ANY flag in `mask` set? */
final def hasFlag(mask: Long): Boolean = {
if (!isCompilerUniverse && needsInitialize(isFlagRelated = true, mask = mask)) initialize
(flags & mask) != 0
}
/** Does symbol have ALL the flags in `mask` set? */
final def hasAllFlags(mask: Long): Boolean = {
if (!isCompilerUniverse && needsInitialize(isFlagRelated = true, mask = mask)) initialize
(flags & mask) == mask
}
def setFlag(mask: Long): this.type = { _rawflags |= mask ; this }
def resetFlag(mask: Long): this.type = { _rawflags &= ~mask ; this }
def resetFlags() { rawflags &= TopLevelCreationFlags }
/** Default implementation calls the generic string function, which
* will print overloaded flags as . Subclasses
* of Symbol refine.
*/
override def resolveOverloadedFlag(flag: Long): String = Flags.flagToString(flag)
/** Set the symbol's flags to the given value, asserting
* that the previous value was 0.
*/
def initFlags(mask: Long): this.type = {
assert(rawflags == 0L, symbolCreationString)
_rawflags = mask
this
}
final def flags: Long = {
if (Statistics.hotEnabled) Statistics.incCounter(flagsCount)
val fs = _rawflags & phase.flagMask
(fs | ((fs & LateFlags) >>> LateShift)) & ~(fs >>> AntiShift)
}
def flags_=(fs: Long) = _rawflags = fs
def rawflags_=(x: Long) { _rawflags = x }
final def hasGetter = isTerm && nme.isLocalName(name)
final def isInitializedToDefault = !isType && hasAllFlags(DEFAULTINIT | ACCESSOR)
final def isStaticModule = isModule && isStatic && !isMethod
final def isThisSym = isTerm && owner.thisSym == this
final def isError = hasFlag(IS_ERROR)
final def isErroneous = isError || isInitialized && tpe.isErroneous
def isHigherOrderTypeParameter = owner.isTypeParameterOrSkolem
// class C extends D( { class E { ... } ... } ). Here, E is a class local to a constructor
def isClassLocalToConstructor = false
final def isDerivedValueClass =
isClass && !hasFlag(PACKAGE | TRAIT) &&
info.firstParent.typeSymbol == AnyValClass && !isPrimitiveValueClass
final def isMethodWithExtension =
isMethod && owner.isDerivedValueClass && !isParamAccessor && !isConstructor && !hasFlag(SUPERACCESSOR) && !isTermMacro
final def isAnonymousFunction = isSynthetic && (name containsName tpnme.ANON_FUN_NAME)
final def isDefinedInPackage = effectiveOwner.isPackageClass
final def needsFlatClasses = phase.flatClasses && rawowner != NoSymbol && !rawowner.isPackageClass
/** change name by appending $$
* Do the same for any accessed symbols or setters/getters.
* Implementation in TermSymbol.
*/
def expandName(base: Symbol) { }
// In java.lang, Predef, or scala package/package object
def isInDefaultNamespace = UnqualifiedOwners(effectiveOwner)
/** The owner, skipping package objects.
*/
def effectiveOwner = owner.skipPackageObject
/** If this is a package object or its implementing class, its owner: otherwise this.
*/
def skipPackageObject: Symbol = this
/** If this is a constructor, its owner: otherwise this.
*/
final def skipConstructor: Symbol = if (isConstructor) owner else this
/** Conditions where we omit the prefix when printing a symbol, to avoid
* unpleasantries like Predef.String, $iw.$iw.Foo and .Bippy.
*/
final def isOmittablePrefix = /*!settings.debug.value &&*/ (
UnqualifiedOwners(skipPackageObject)
|| isEmptyPrefix
)
def isEmptyPrefix = (
isEffectiveRoot // has no prefix for real, or
|| isAnonOrRefinementClass // has uninteresting or prefix
|| nme.isReplWrapperName(name) // has ugly $iw. prefix (doesn't call isInterpreterWrapper due to nesting)
)
def isFBounded = info match {
case TypeBounds(_, _) => info.baseTypeSeq exists (_ contains this)
case _ => false
}
/** Is symbol a monomorphic type?
* assumption: if a type starts out as monomorphic, it will not acquire
* type parameters in later phases.
*/
final def isMonomorphicType =
isType && {
val info = originalInfo
info.isComplete && !info.isHigherKinded
}
def isStrictFP = hasAnnotation(ScalaStrictFPAttr) || (enclClass hasAnnotation ScalaStrictFPAttr)
def isSerializable = (
info.baseClasses.exists(p => p == SerializableClass || p == JavaSerializableClass)
|| hasAnnotation(SerializableAttr) // last part can be removed, @serializable annotation is deprecated
)
def hasBridgeAnnotation = hasAnnotation(BridgeClass)
def isDeprecated = hasAnnotation(DeprecatedAttr)
def deprecationMessage = getAnnotation(DeprecatedAttr) flatMap (_ stringArg 0)
def deprecationVersion = getAnnotation(DeprecatedAttr) flatMap (_ stringArg 1)
def deprecatedParamName = getAnnotation(DeprecatedNameAttr) flatMap (_ symbolArg 0)
def hasDeprecatedInheritanceAnnotation
= hasAnnotation(DeprecatedInheritanceAttr)
def deprecatedInheritanceMessage
= getAnnotation(DeprecatedInheritanceAttr) flatMap (_ stringArg 0)
def deprecatedInheritanceVersion
= getAnnotation(DeprecatedInheritanceAttr) flatMap (_ stringArg 1)
def hasDeprecatedOverridingAnnotation
= hasAnnotation(DeprecatedOverridingAttr)
def deprecatedOverridingMessage
= getAnnotation(DeprecatedOverridingAttr) flatMap (_ stringArg 0)
def deprecatedOverridingVersion
= getAnnotation(DeprecatedOverridingAttr) flatMap (_ stringArg 1)
// !!! when annotation arguments are not literal strings, but any sort of
// assembly of strings, there is a fair chance they will turn up here not as
// Literal(const) but some arbitrary AST. However nothing in the compiler
// prevents someone from writing a @migration annotation with a calculated
// string. So this needs attention. For now the fact that migration is
// private[scala] ought to provide enough protection.
def hasMigrationAnnotation = hasAnnotation(MigrationAnnotationClass)
def migrationMessage = getAnnotation(MigrationAnnotationClass) flatMap { _.stringArg(0) }
def migrationVersion = getAnnotation(MigrationAnnotationClass) flatMap { _.stringArg(1) }
def elisionLevel = getAnnotation(ElidableMethodClass) flatMap { _.intArg(0) }
def implicitNotFoundMsg = getAnnotation(ImplicitNotFoundClass) flatMap { _.stringArg(0) }
def isCompileTimeOnly = hasAnnotation(CompileTimeOnlyAttr)
def compileTimeOnlyMessage = getAnnotation(CompileTimeOnlyAttr) flatMap (_ stringArg 0)
/** Is this symbol an accessor method for outer? */
final def isOuterAccessor = {
hasFlag(STABLE | ARTIFACT) &&
originalName == nme.OUTER
}
/** Is this symbol an accessor method for outer? */
final def isOuterField = {
hasFlag(ARTIFACT) &&
originalName == nme.OUTER_LOCAL
}
/** Does this symbol denote a stable value? */
def isStable = false
/** Does this symbol denote the primary constructor of its enclosing class? */
final def isPrimaryConstructor =
isConstructor && owner.primaryConstructor == this
/** Does this symbol denote an auxiliary constructor of its enclosing class? */
final def isAuxiliaryConstructor =
isConstructor && !isPrimaryConstructor
/** Is this symbol a synthetic apply or unapply method in a companion object of a case class? */
final def isCaseApplyOrUnapply =
isMethod && isCase && isSynthetic
/** Is this symbol a trait which needs an implementation class? */
final def needsImplClass = (
isTrait
&& (!isInterface || hasFlag(lateINTERFACE))
&& !isImplClass
)
/** Is this a symbol which exists only in the implementation class, not in its trait? */
final def isImplOnly = isPrivate || (
(owner.isTrait || owner.isImplClass) && (
hasAllFlags(LIFTED | MODULE | METHOD)
|| isConstructor
|| hasFlag(notPRIVATE | LIFTED) && !hasFlag(ACCESSOR | SUPERACCESSOR | MODULE)
)
)
final def isModuleVar = hasFlag(MODULEVAR)
/** Is this symbol static (i.e. with no outer instance)?
* Q: When exactly is a sym marked as STATIC?
* A: If it's a member of a toplevel object, or of an object contained in a toplevel object, or any number of levels deep.
* http://groups.google.com/group/scala-internals/browse_thread/thread/d385bcd60b08faf6
*/
def isStatic = (this hasFlag STATIC) || owner.isStaticOwner
/** Is this symbol a static constructor? */
final def isStaticConstructor: Boolean =
isStaticMember && isClassConstructor
/** Is this symbol a static member of its class? (i.e. needs to be implemented as a Java static?) */
final def isStaticMember: Boolean =
hasFlag(STATIC) || owner.isImplClass
/** Does this symbol denote a class that defines static symbols? */
final def isStaticOwner: Boolean =
isPackageClass || isModuleClass && isStatic
def isTopLevelModule = hasFlag(MODULE) && owner.isPackageClass
/** Is this symbol effectively final? I.e, it cannot be overridden */
final def isEffectivelyFinal: Boolean = (
(this hasFlag FINAL | PACKAGE)
|| isModuleOrModuleClass && (owner.isPackageClass || !settings.overrideObjects.value)
|| isTerm && (
isPrivate
|| isLocal
|| owner.isClass && owner.isEffectivelyFinal
)
)
/** Is this symbol locally defined? I.e. not accessed from outside `this` instance */
final def isLocal: Boolean = owner.isTerm
/** Is this symbol a constant? */
final def isConstant: Boolean = isStable && isConstantType(tpe.resultType)
/** Is this class nested in another class or module (not a package)? */
def isNestedClass = false
/** Is this class locally defined?
* A class is local, if
* - it is anonymous, or
* - its owner is a value
* - it is defined within a local class
*/
def isLocalClass = false
def isStableClass = false
/* code for fixing nested objects
override final def isModuleClass: Boolean =
super.isModuleClass && !isExpandedModuleClass
*/
/** Is this class or type defined as a structural refinement type?
*/
final def isStructuralRefinement: Boolean =
(isClass || isType || isModule) && info.normalize/*.underlying*/.isStructuralRefinement
/** Is this a term symbol only defined in a refinement (so that it needs
* to be accessed by reflection)?
*/
def isOnlyRefinementMember: Boolean =
isTerm && // type members are not affected
owner.isRefinementClass && // owner must be a refinement class
(owner.info decl name) == this && // symbol must be explicitly declared in the refinement (not synthesized from glb)
allOverriddenSymbols.isEmpty && // symbol must not override a symbol in a base class
!isConstant // symbol must not be a constant. Question: Can we exclude @inline methods as well?
final def isStructuralRefinementMember = owner.isStructuralRefinement && isPossibleInRefinement && isPublic
final def isPossibleInRefinement = !isConstructor && !isOverridingSymbol
/** Is this symbol a member of class `clazz`? */
def isMemberOf(clazz: Symbol) =
clazz.info.member(name).alternatives contains this
/** A a member of class `base` is incomplete if
* (1) it is declared deferred or
* (2) it is abstract override and its super symbol in `base` is
* nonexistent or incomplete.
*
* @param base ...
* @return ...
*/
final def isIncompleteIn(base: Symbol): Boolean =
this.isDeferred ||
(this hasFlag ABSOVERRIDE) && {
val supersym = superSymbol(base)
supersym == NoSymbol || supersym.isIncompleteIn(base)
}
// Does not always work if the rawInfo is a SourcefileLoader, see comment
// in "def coreClassesFirst" in Global.
def exists = !owner.isPackageClass || { rawInfo.load(this); rawInfo != NoType }
final def isInitialized: Boolean =
validTo != NoPeriod
/** Can this symbol be loaded by a reflective mirror?
*
* Scalac relies on `ScalaSignature' annotation to retain symbols across compilation runs.
* Such annotations (also called "pickles") are applied on top-level classes and include information
* about all symbols reachable from the annotee. However, local symbols (e.g. classes or definitions local to a block)
* are typically unreachable and information about them gets lost.
*
* This method is useful for macro writers who wish to save certain ASTs to be used at runtime.
* With `isLocatable' it's possible to check whether a tree can be retained as is, or it needs special treatment.
*/
final def isLocatable: Boolean = {
if (this == NoSymbol) return false
if (isRoot || isRootPackage) return true
if (!owner.isLocatable) return false
if (owner.isTerm) return false
if (isLocalDummy) return false
if (isAliasType) return true
if (isType && isNonClassType) return false
if (isRefinementClass) return false
return true
}
/** The variance of this symbol as an integer */
final def variance: Int =
if (isCovariant) 1
else if (isContravariant) -1
else 0
/** The sequence number of this parameter symbol among all type
* and value parameters of symbol's owner. -1 if symbol does not
* appear among the parameters of its owner.
*/
def paramPos: Int = {
def searchIn(tpe: Type, base: Int): Int = {
def searchList(params: List[Symbol], fallback: Type): Int = {
val idx = params indexOf this
if (idx >= 0) idx + base
else searchIn(fallback, base + params.length)
}
tpe match {
case PolyType(tparams, res) => searchList(tparams, res)
case MethodType(params, res) => searchList(params, res)
case _ => -1
}
}
searchIn(owner.info, 0)
}
// ------ owner attribute --------------------------------------------------------------
def owner: Symbol = {
if (Statistics.hotEnabled) Statistics.incCounter(ownerCount)
rawowner
}
// TODO - don't allow the owner to be changed without checking invariants, at least
// when under some flag. Define per-phase invariants for owner/owned relationships,
// e.g. after flatten all classes are owned by package classes, there are lots and
// lots of these to be declared (or more realistically, discovered.)
def owner_=(owner: Symbol) {
// don't keep the original owner in presentation compiler runs
// (the map will grow indefinitely, and the only use case is the
// backend).
if (!forInteractive) {
if (originalOwner contains this) ()
else originalOwner(this) = rawowner
}
assert(isCompilerUniverse, "owner_= is not thread-safe; cannot be run in reflexive code")
if (traceSymbolActivity)
traceSymbols.recordNewSymbolOwner(this, owner)
_rawowner = owner
}
def ownerChain: List[Symbol] = this :: owner.ownerChain
def originalOwnerChain: List[Symbol] = this :: originalOwner.getOrElse(this, rawowner).originalOwnerChain
// Non-classes skip self and return rest of owner chain; overridden in ClassSymbol.
def enclClassChain: List[Symbol] = owner.enclClassChain
def ownersIterator: Iterator[Symbol] = new Iterator[Symbol] {
private var current = Symbol.this
def hasNext = current ne NoSymbol
def next = { val r = current; current = current.owner; r }
}
/** Same as `ownerChain contains sym` but more efficient, and
* with a twist for refinement classes (see RefinementClassSymbol.)
*/
def hasTransOwner(sym: Symbol): Boolean = {
var o = this
while ((o ne sym) && (o ne NoSymbol)) o = o.owner
(o eq sym)
}
// ------ name attribute --------------------------------------------------------------
/** If this symbol has an expanded name, its original name, otherwise its name itself.
* @see expandName
*/
def originalName: Name = nme.originalName(nme.dropLocalSuffix(name))
/** The name of the symbol before decoding, e.g. `\$eq\$eq` instead of `==`.
*/
def encodedName: String = name.toString
/** The decoded name of the symbol, e.g. `==` instead of `\$eq\$eq`.
*/
def decodedName: String = nme.dropLocalSuffix(name).decode
private def addModuleSuffix(n: Name): Name =
if (needsModuleSuffix) n append nme.MODULE_SUFFIX_STRING else n
def moduleSuffix: String = (
if (needsModuleSuffix) nme.MODULE_SUFFIX_STRING
else ""
)
/** Whether this symbol needs nme.MODULE_SUFFIX_STRING (aka $) appended on the java platform.
*/
def needsModuleSuffix = (
hasModuleFlag
&& !isMethod
&& !isImplClass
&& !isJavaDefined
)
/** These should be moved somewhere like JavaPlatform.
*/
def javaSimpleName: Name = addModuleSuffix(nme.dropLocalSuffix(simpleName))
def javaBinaryName: Name = addModuleSuffix(fullNameInternal('/'))
def javaClassName: String = addModuleSuffix(fullNameInternal('.')).toString
/** The encoded full path name of this symbol, where outer names and inner names
* are separated by `separator` characters.
* Never translates expansions of operators back to operator symbol.
* Never adds id.
* Drops package objects.
*/
final def fullName(separator: Char): String = fullNameAsName(separator).toString
/** Doesn't drop package objects, for those situations (e.g. classloading)
* where the true path is needed.
*/
private def fullNameInternal(separator: Char): Name = (
if (isRoot || isRootPackage || this == NoSymbol) name
else if (owner.isEffectiveRoot) name
else ((effectiveOwner.enclClass.fullNameAsName(separator) append separator): Name) append name
)
def fullNameAsName(separator: Char): Name = nme.dropLocalSuffix(fullNameInternal(separator))
/** The encoded full path name of this symbol, where outer names and inner names
* are separated by periods.
*/
final def fullName: String = fullName('.')
/**
* Symbol creation implementations.
*/
protected def createAbstractTypeSymbol(name: TypeName, pos: Position, newFlags: Long): AbstractTypeSymbol =
new AbstractTypeSymbol(this, pos, name) initFlags newFlags
protected def createAliasTypeSymbol(name: TypeName, pos: Position, newFlags: Long): AliasTypeSymbol =
new AliasTypeSymbol(this, pos, name) initFlags newFlags
protected def createTypeSkolemSymbol(name: TypeName, origin: AnyRef, pos: Position, newFlags: Long): TypeSkolem =
new TypeSkolem(this, pos, name, origin) initFlags newFlags
protected def createClassSymbol(name: TypeName, pos: Position, newFlags: Long): ClassSymbol =
new ClassSymbol(this, pos, name) initFlags newFlags
protected def createModuleClassSymbol(name: TypeName, pos: Position, newFlags: Long): ModuleClassSymbol =
new ModuleClassSymbol(this, pos, name) initFlags newFlags
protected def createPackageClassSymbol(name: TypeName, pos: Position, newFlags: Long): PackageClassSymbol =
new PackageClassSymbol(this, pos, name) initFlags newFlags
protected def createRefinementClassSymbol(pos: Position, newFlags: Long): RefinementClassSymbol =
new RefinementClassSymbol(this, pos) initFlags newFlags
protected def createPackageObjectClassSymbol(pos: Position, newFlags: Long): PackageObjectClassSymbol =
new PackageObjectClassSymbol(this, pos) initFlags newFlags
protected def createImplClassSymbol(name: TypeName, pos: Position, newFlags: Long): ClassSymbol =
new ClassSymbol(this, pos, name) with ImplClassSymbol initFlags newFlags
protected def createTermSymbol(name: TermName, pos: Position, newFlags: Long): TermSymbol =
new TermSymbol(this, pos, name) initFlags newFlags
protected def createMethodSymbol(name: TermName, pos: Position, newFlags: Long): MethodSymbol =
new MethodSymbol(this, pos, name) initFlags newFlags
protected def createModuleSymbol(name: TermName, pos: Position, newFlags: Long): ModuleSymbol =
new ModuleSymbol(this, pos, name) initFlags newFlags
protected def createPackageSymbol(name: TermName, pos: Position, newFlags: Long): ModuleSymbol =
new ModuleSymbol(this, pos, name) initFlags newFlags
protected def createValueParameterSymbol(name: TermName, pos: Position, newFlags: Long): TermSymbol =
new TermSymbol(this, pos, name) initFlags newFlags
protected def createValueMemberSymbol(name: TermName, pos: Position, newFlags: Long): TermSymbol =
new TermSymbol(this, pos, name) initFlags newFlags
final def newTermSymbol(name: TermName, pos: Position = NoPosition, newFlags: Long = 0L): TermSymbol = {
if ((newFlags & METHOD) != 0)
createMethodSymbol(name, pos, newFlags)
else if ((newFlags & PACKAGE) != 0)
createPackageSymbol(name, pos, newFlags | PackageFlags)
else if ((newFlags & MODULE) != 0)
createModuleSymbol(name, pos, newFlags)
else if ((newFlags & PARAM) != 0)
createValueParameterSymbol(name, pos, newFlags)
else
createValueMemberSymbol(name, pos, newFlags)
}
final def newClassSymbol(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): ClassSymbol = {
if (name == tpnme.REFINE_CLASS_NAME)
createRefinementClassSymbol(pos, newFlags)
else if ((newFlags & PACKAGE) != 0)
createPackageClassSymbol(name, pos, newFlags | PackageFlags)
else if (name == tpnme.PACKAGE)
createPackageObjectClassSymbol(pos, newFlags)
else if ((newFlags & MODULE) != 0)
createModuleClassSymbol(name, pos, newFlags)
else if ((newFlags & IMPLCLASS) != 0)
createImplClassSymbol(name, pos, newFlags)
else
createClassSymbol(name, pos, newFlags)
}
final def newNonClassSymbol(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): TypeSymbol = {
if ((newFlags & DEFERRED) != 0)
createAbstractTypeSymbol(name, pos, newFlags)
else
createAliasTypeSymbol(name, pos, newFlags)
}
def newTypeSymbol(name: TypeName, pos: Position = NoPosition, newFlags: Long = 0L): TypeSymbol =
newNonClassSymbol(name, pos, newFlags)
/** The class or term up to which this symbol is accessible,
* or RootClass if it is public. As java protected statics are
* otherwise completely inaccessible in scala, they are treated
* as public.
*/
def accessBoundary(base: Symbol): Symbol = {
if (hasFlag(PRIVATE) || isLocal) owner
else if (hasAllFlags(PROTECTED | STATIC | JAVA)) enclosingRootClass
else if (hasAccessBoundary && !phase.erasedTypes) privateWithin
else if (hasFlag(PROTECTED)) base
else enclosingRootClass
}
def isLessAccessibleThan(other: Symbol): Boolean = {
val tb = this.accessBoundary(owner)
val ob1 = other.accessBoundary(owner)
val ob2 = ob1.linkedClassOfClass
var o = tb
while (o != NoSymbol && o != ob1 && o != ob2) {
o = o.owner
}
o != NoSymbol && o != tb
}
/** See comment in HasFlags for how privateWithin combines with flags.
*/
private[this] var _privateWithin: Symbol = _
def privateWithin = {
if (!isCompilerUniverse && needsInitialize(isFlagRelated = false, mask = 0)) initialize
_privateWithin
}
def privateWithin_=(sym: Symbol) { _privateWithin = sym }
def setPrivateWithin(sym: Symbol): this.type = { privateWithin_=(sym) ; this }
/** Does symbol have a private or protected qualifier set? */
final def hasAccessBoundary = (privateWithin != null) && (privateWithin != NoSymbol)
// ------ info and type -------------------------------------------------------------------
private[Symbols] var infos: TypeHistory = null
def originalInfo = {
if (infos eq null) null
else {
var is = infos
while (is.prev ne null) { is = is.prev }
is.info
}
}
/** Get type. The type of a symbol is:
* for a type symbol, the type corresponding to the symbol itself,
* @M you should use tpeHK for a type symbol with type parameters if
* the kind of the type need not be *, as tpe introduces dummy arguments
* to generate a type of kind *
* for a term symbol, its usual type.
* See the tpe/tpeHK overrides in TypeSymbol for more.
*
* For type symbols, `tpe` is different than `info`. `tpe` returns a typeRef
* to the type symbol, `info` returns the type information of the type symbol,
* e.g. a ClassInfoType for classes or a TypeBounds for abstract types.
*/
def tpe: Type = info
def tpeHK: Type = tpe
/** Get type info associated with symbol at current phase, after
* ensuring that symbol is initialized (i.e. type is completed).
*/
def info: Type = try {
var cnt = 0
while (validTo == NoPeriod) {
//if (settings.debug.value) System.out.println("completing " + this);//DEBUG
assert(infos ne null, this.name)
assert(infos.prev eq null, this.name)
val tp = infos.info
//if (settings.debug.value) System.out.println("completing " + this.rawname + tp.getClass());//debug
if ((_rawflags & LOCKED) != 0L) { // rolled out once for performance
lock {
setInfo(ErrorType)
throw CyclicReference(this, tp)
}
} else {
_rawflags |= LOCKED
// activeLocks += 1
// lockedSyms += this
}
val current = phase
try {
assertCorrectThread()
phase = phaseOf(infos.validFrom)
tp.complete(this)
} finally {
unlock()
phase = current
}
cnt += 1
// allow for two completions:
// one: sourceCompleter to LazyType, two: LazyType to completed type
if (cnt == 3) abort("no progress in completing " + this + ":" + tp)
}
rawInfo
}
catch {
case ex: CyclicReference =>
debugwarn("... hit cycle trying to complete " + this.fullLocationString)
throw ex
}
def info_=(info: Type) {
assert(info ne null)
infos = TypeHistory(currentPeriod, info, null)
unlock()
_validTo = if (info.isComplete) currentPeriod else NoPeriod
}
/** Set initial info. */
def setInfo(info: Type): this.type = { info_=(info); this }
/** Modifies this symbol's info in place. */
def modifyInfo(f: Type => Type): this.type = setInfo(f(info))
/** Substitute second list of symbols for first in current info. */
def substInfo(syms0: List[Symbol], syms1: List[Symbol]): this.type =
if (syms0.isEmpty) this
else modifyInfo(_.substSym(syms0, syms1))
def setInfoOwnerAdjusted(info: Type): this.type = setInfo(info atOwner this)
/** Set the info and enter this symbol into the owner's scope. */
def setInfoAndEnter(info: Type): this.type = {
setInfo(info)
owner.info.decls enter this
this
}
/** Set new info valid from start of this phase. */
def updateInfo(info: Type): Symbol = {
val pid = phaseId(infos.validFrom)
assert(pid <= phase.id, (pid, phase.id))
if (pid == phase.id) infos = infos.prev
infos = TypeHistory(currentPeriod, info, infos)
_validTo = if (info.isComplete) currentPeriod else NoPeriod
this
}
def hasRawInfo: Boolean = infos ne null
def hasCompleteInfo = hasRawInfo && rawInfo.isComplete
/** Return info without checking for initialization or completing */
def rawInfo: Type = {
var infos = this.infos
assert(infos != null)
val curPeriod = currentPeriod
val curPid = phaseId(curPeriod)
if (validTo != NoPeriod) {
// skip any infos that concern later phases
while (curPid < phaseId(infos.validFrom) && infos.prev != null)
infos = infos.prev
if (validTo < curPeriod) {
assertCorrectThread()
// adapt any infos that come from previous runs
val current = phase
try {
infos = adaptInfos(infos)
//assert(runId(validTo) == currentRunId, name)
//assert(runId(infos.validFrom) == currentRunId, name)
if (validTo < curPeriod) {
var itr = infoTransformers.nextFrom(phaseId(validTo))
infoTransformers = itr; // caching optimization
while (itr.pid != NoPhase.id && itr.pid < current.id) {
phase = phaseWithId(itr.pid)
val info1 = itr.transform(this, infos.info)
if (info1 ne infos.info) {
infos = TypeHistory(currentPeriod + 1, info1, infos)
this.infos = infos
}
_validTo = currentPeriod + 1 // to enable reads from same symbol during info-transform
itr = itr.next
}
_validTo = if (itr.pid == NoPhase.id) curPeriod
else period(currentRunId, itr.pid)
}
} finally {
phase = current
}
}
}
infos.info
}
// adapt to new run in fsc.
private def adaptInfos(infos: TypeHistory): TypeHistory = {
assert(isCompilerUniverse)
if (infos == null || runId(infos.validFrom) == currentRunId) {
infos
} else {
val prev1 = adaptInfos(infos.prev)
if (prev1 ne infos.prev) prev1
else {
val pid = phaseId(infos.validFrom)
_validTo = period(currentRunId, pid)
phase = phaseWithId(pid)
val info1 = (
if (isPackageClass) infos.info
else adaptToNewRunMap(infos.info)
)
if (info1 eq infos.info) {
infos.validFrom = validTo
infos
} else {
this.infos = TypeHistory(validTo, info1, prev1)
this.infos
}
}
}
}
/** Raises a `MissingRequirementError` if this symbol is a `StubSymbol` */
def failIfStub() {}
/** Initialize the symbol */
final def initialize: this.type = {
if (!isInitialized) info
this
}
/** Called when the programmer requests information that might require initialization of the underlying symbol.
*
* `isFlagRelated` and `mask` describe the nature of this information.
* isFlagRelated = true means that the programmer needs particular bits in flags.
* isFlagRelated = false means that the request is unrelated to flags (annotations or privateWithin).
*
* In our current architecture, symbols for top-level classes and modules
* are created as dummies. Package symbols just call newClass(name) or newModule(name) and
* consider their job done.
*
* In order for such a dummy to provide meaningful info (e.g. a list of its members),
* it needs to go through unpickling. Unpickling is a process of reading Scala metadata
* from ScalaSignature annotations and assigning it to symbols and types.
*
* A single unpickling session takes a top-level class or module, parses the ScalaSignature annotation
* and then reads metadata for the unpicklee, its companion (if any) and all their members recursively
* (i.e. the pickle not only contains info about directly nested classes/modules, but also about
* classes/modules nested into those and so on).
*
* Unpickling is triggered automatically whenever typeSignature (info in compiler parlance) is called.
* This happens because package symbols assign completer thunks to the dummies they create.
* Therefore metadata loading happens lazily and transparently.
*
* Almost transparently. Unfortunately metadata isn't limited to just signatures (i.e. lists of members).
* It also includes flags (which determine e.g. whether a class is sealed or not), annotations and privateWithin.
* This gives rise to unpleasant effects like in SI-6277, when a flag test called on an uninitialize symbol
* produces incorrect results.
*
* One might think that the solution is simple: automatically call the completer whenever one needs
* flags, annotations and privateWithin - just like it's done for typeSignature. Unfortunately, this
* leads to weird crashes in scalac, and currently we can't attempt to fix the core of the compiler
* risk stability a few weeks before the final release.
*
* However we do need to fix this for runtime reflection, since it's not something we'd like to
* expose to reflection users. Therefore a proposed solution is to check whether we're in a
* runtime reflection universe and if yes then to commence initialization.
*/
protected def needsInitialize(isFlagRelated: Boolean, mask: Long) =
!isInitialized && (flags & LOCKED) == 0 && shouldTriggerCompleter(this, if (infos ne null) infos.info else null, isFlagRelated, mask)
/** Was symbol's type updated during given phase? */
final def isUpdatedAt(pid: Phase#Id): Boolean = {
assert(isCompilerUniverse)
var infos = this.infos
while ((infos ne null) && phaseId(infos.validFrom) != pid + 1) infos = infos.prev
infos ne null
}
/** Was symbol's type updated during given phase? */
final def hasTypeAt(pid: Phase#Id): Boolean = {
assert(isCompilerUniverse)
var infos = this.infos
while ((infos ne null) && phaseId(infos.validFrom) > pid) infos = infos.prev
infos ne null
}
/** Modify term symbol's type so that a raw type C is converted to an existential C[_]
*
* This is done in checkAccessible and overriding checks in refchecks
* We can't do this on class loading because it would result in infinite cycles.
*/
final def cookJavaRawInfo() {
if (hasFlag(TRIEDCOOKING)) return else setFlag(TRIEDCOOKING) // only try once...
val oldInfo = info
doCookJavaRawInfo()
}
protected def doCookJavaRawInfo(): Unit
/** The type constructor of a symbol is:
* For a type symbol, the type corresponding to the symbol itself,
* excluding parameters.
* Not applicable for term symbols.
*/
def typeConstructor: Type =
abort("typeConstructor inapplicable for " + this)
/** The logic approximately boils down to finding the most recent phase
* which immediately follows any of parser, namer, typer, or erasure.
* In effect that means this will return one of:
*
* - packageobjects (follows namer)
* - superaccessors (follows typer)
* - lazyvals (follows erasure)
* - null
*/
private def unsafeTypeParamPhase = {
var ph = phase
while (ph.prev.keepsTypeParams)
ph = ph.prev
ph
}
/** The type parameters of this symbol, without ensuring type completion.
* assumption: if a type starts out as monomorphic, it will not acquire
* type parameters later.
*/
def unsafeTypeParams: List[Symbol] =
if (isMonomorphicType) Nil
else atPhase(unsafeTypeParamPhase)(rawInfo.typeParams)
/** The type parameters of this symbol.
* assumption: if a type starts out as monomorphic, it will not acquire
* type parameters later.
*/
def typeParams: List[Symbol] =
if (isMonomorphicType) Nil
else {
// analogously to the "info" getter, here we allow for two completions:
// one: sourceCompleter to LazyType, two: LazyType to completed type
if (validTo == NoPeriod)
atPhase(phaseOf(infos.validFrom))(rawInfo load this)
if (validTo == NoPeriod)
atPhase(phaseOf(infos.validFrom))(rawInfo load this)
rawInfo.typeParams
}
/** The value parameter sections of this symbol.
*/
def paramss: List[List[Symbol]] = info.paramss
/** The least proper supertype of a class; includes all parent types
* and refinement where needed. You need to compute that in a situation like this:
* {
* class C extends P { ... }
* new C
* }
*/
def classBound: Type = {
val tp = refinedType(info.parents, owner)
// SI-4589 refinedType only creates a new refinement class symbol before erasure; afterwards
// the first parent class is returned, to which we must not add members.
if (!phase.erasedTypes) {
val thistp = tp.typeSymbol.thisType
val oldsymbuf = new ListBuffer[Symbol]
val newsymbuf = new ListBuffer[Symbol]
for (sym <- info.decls) {
// todo: what about public references to private symbols?
if (sym.isPublic && !sym.isConstructor) {
oldsymbuf += sym
newsymbuf += (
if (sym.isClass)
tp.typeSymbol.newAbstractType(sym.name.toTypeName, sym.pos).setInfo(sym.existentialBound)
else
sym.cloneSymbol(tp.typeSymbol))
}
}
val oldsyms = oldsymbuf.toList
val newsyms = newsymbuf.toList
for (sym <- newsyms) {
addMember(thistp, tp, sym modifyInfo (_ substThisAndSym(this, thistp, oldsyms, newsyms)))
}
}
tp
}
/** If we quantify existentially over this symbol,
* the bound of the type variable that stands for it
* pre: symbol is a term, a class, or an abstract type (no alias type allowed)
*/
def existentialBound: Type
/** Reset symbol to initial state
*/
def reset(completer: Type): this.type = {
resetFlags()
infos = null
_validTo = NoPeriod
//limit = NoPhase.id
setInfo(completer)
}
/**
* Adds the interface scala.Serializable to the parents of a ClassInfoType.
* Note that the tree also has to be updated accordingly.
*/
def makeSerializable() {
info match {
case ci @ ClassInfoType(_, _, _) =>
setInfo(ci.copy(parents = ci.parents :+ SerializableClass.tpe))
case i =>
abort("Only ClassInfoTypes can be made serializable: "+ i)
}
}
// ----- setters implemented in selected subclasses -------------------------------------
def typeOfThis_=(tp: Type) { throw new UnsupportedOperationException("typeOfThis_= inapplicable for " + this) }
def sourceModule_=(sym: Symbol) { throw new UnsupportedOperationException("sourceModule_= inapplicable for " + this) }
def addChild(sym: Symbol) { throw new UnsupportedOperationException("addChild inapplicable for " + this) }
// ----- annotations ------------------------------------------------------------
// null is a marker that they still need to be obtained.
private[this] var _annotations: List[AnnotationInfo] = Nil
def annotationsString = if (annotations.isEmpty) "" else annotations.mkString("(", ", ", ")")
/** After the typer phase (before, look at the definition's Modifiers), contains
* the annotations attached to member a definition (class, method, type, field).
*/
def annotations: List[AnnotationInfo] = {
if (!isCompilerUniverse && needsInitialize(isFlagRelated = false, mask = 0)) initialize
_annotations
}
def setAnnotations(annots: List[AnnotationInfo]): this.type = {
_annotations = annots
this
}
def withAnnotations(annots: List[AnnotationInfo]): this.type =
setAnnotations(annots ::: annotations)
def withoutAnnotations: this.type =
setAnnotations(Nil)
def filterAnnotations(p: AnnotationInfo => Boolean): this.type =
setAnnotations(annotations filter p)
def addAnnotation(annot: AnnotationInfo): this.type =
setAnnotations(annot :: annotations)
// Convenience for the overwhelmingly common case
def addAnnotation(sym: Symbol, args: Tree*): this.type = {
// The assertion below is meant to prevent from issues like SI-7009 but it's disabled
// due to problems with cycles while compiling Scala library. It's rather shocking that
// just checking if sym is monomorphic type introduces nasty cycles. We are definitively
// forcing too much because monomorphism is a local property of a type that can be checked
// syntactically
// assert(sym.initialize.isMonomorphicType, sym)
addAnnotation(AnnotationInfo(sym.tpe, args.toList, Nil))
}
/** Use that variant if you want to pass (for example) an applied type */
def addAnnotation(tp: Type, args: Tree*): this.type = {
assert(tp.typeParams.isEmpty, tp)
addAnnotation(AnnotationInfo(tp, args.toList, Nil))
}
// ------ comparisons ----------------------------------------------------------------
/** A total ordering between symbols that refines the class
* inheritance graph (i.e. subclass.isLess(superclass) always holds).
* the ordering is given by: (_.isType, -_.baseTypeSeq.length) for type symbols, followed by `id`.
*/
final def isLess(that: Symbol): Boolean = {
def baseTypeSeqLength(sym: Symbol) =
if (sym.isAbstractType) 1 + sym.info.bounds.hi.baseTypeSeq.length
else sym.info.baseTypeSeq.length
if (this.isType)
(that.isType &&
{ val diff = baseTypeSeqLength(this) - baseTypeSeqLength(that)
diff > 0 || diff == 0 && this.id < that.id })
else
that.isType || this.id < that.id
}
/** A partial ordering between symbols.
* (this isNestedIn that) holds iff this symbol is defined within
* a class or method defining that symbol
*/
final def isNestedIn(that: Symbol): Boolean =
owner == that || owner != NoSymbol && (owner isNestedIn that)
/** Is this class symbol a subclass of that symbol,
* and is this class symbol also different from Null or Nothing? */
def isNonBottomSubClass(that: Symbol): Boolean = false
/** Overridden in NullClass and NothingClass for custom behavior.
*/
def isSubClass(that: Symbol) = isNonBottomSubClass(that)
final def isNumericSubClass(that: Symbol): Boolean =
definitions.isNumericSubClass(this, that)
final def isWeakSubClass(that: Symbol) =
isSubClass(that) || isNumericSubClass(that)
// ------ overloaded alternatives ------------------------------------------------------
def alternatives: List[Symbol] =
if (isOverloaded) info.asInstanceOf[OverloadedType].alternatives
else this :: Nil
def filter(cond: Symbol => Boolean): Symbol =
if (isOverloaded) {
val alts = alternatives
val alts1 = alts filter cond
if (alts1 eq alts) this
else if (alts1.isEmpty) NoSymbol
else if (alts1.tail.isEmpty) alts1.head
else owner.newOverloaded(info.prefix, alts1)
}
else if (cond(this)) this
else NoSymbol
def suchThat(cond: Symbol => Boolean): Symbol = {
val result = filter(cond)
assert(!result.isOverloaded, result.alternatives)
result
}
@inline final def map(f: Symbol => Symbol): Symbol = if (this eq NoSymbol) this else f(this)
final def toOption: Option[Symbol] = if (exists) Some(this) else None
// ------ cloneing -------------------------------------------------------------------
/** A clone of this symbol. */
final def cloneSymbol: TypeOfClonedSymbol =
cloneSymbol(owner)
/** A clone of this symbol, but with given owner. */
final def cloneSymbol(newOwner: Symbol): TypeOfClonedSymbol =
cloneSymbol(newOwner, _rawflags)
final def cloneSymbol(newOwner: Symbol, newFlags: Long): TypeOfClonedSymbol =
cloneSymbol(newOwner, newFlags, null)
final def cloneSymbol(newOwner: Symbol, newFlags: Long, newName: Name): TypeOfClonedSymbol = {
val clone = cloneSymbolImpl(newOwner, newFlags)
( clone
setPrivateWithin privateWithin
setInfo (this.info cloneInfo clone)
setAnnotations this.annotations
)
this.attachments.all.foreach(clone.updateAttachment)
if (clone.thisSym != clone)
clone.typeOfThis = (clone.typeOfThis cloneInfo clone)
if (newName ne null)
clone setName asNameType(newName)
clone
}
/** Internal method to clone a symbol's implementation with the given flags and no info. */
def cloneSymbolImpl(owner: Symbol, newFlags: Long): TypeOfClonedSymbol
// ------ access to related symbols --------------------------------------------------
/** The next enclosing class. */
def enclClass: Symbol = if (isClass) this else owner.enclClass
/** The next enclosing method. */
def enclMethod: Symbol = if (isSourceMethod) this else owner.enclMethod
/** The primary constructor of a class. */
def primaryConstructor: Symbol = NoSymbol
/** The self symbol (a TermSymbol) of a class with explicit self type, or else the
* symbol itself (a TypeSymbol).
*
* WARNING: you're probably better off using typeOfThis, as it's more uniform across classes with and without self variables.
*
* Example by Paul:
* scala> trait Foo1 { }
* scala> trait Foo2 { self => }
* scala> intp("Foo1").thisSym
* res0: $r.intp.global.Symbol = trait Foo1
*
* scala> intp("Foo2").thisSym
* res1: $r.intp.global.Symbol = value self
*
* Martin says: The reason `thisSym' is `this' is so that thisType can be this.thisSym.tpe.
* It's a trick to shave some cycles off.
*
* Morale: DO: if (clazz.typeOfThis.typeConstructor ne clazz.typeConstructor) ...
* DON'T: if (clazz.thisSym ne clazz) ...
*
*/
def thisSym: Symbol = this
/** The type of `this` in a class, or else the type of the symbol itself. */
def typeOfThis = thisSym.tpe
/** If symbol is a class, the type this.type in this class,
* otherwise NoPrefix.
* We always have: thisType <:< typeOfThis
*/
def thisType: Type = NoPrefix
/** For a case class, the symbols of the accessor methods, one for each
* argument in the first parameter list of the primary constructor.
* The empty list for all other classes.
*
* This list will be sorted to correspond to the declaration order
* in the constructor parameter
*/
final def caseFieldAccessors: List[Symbol] = {
// We can't rely on the ordering of the case field accessors within decls --
// handling of non-public parameters seems to change the order (see SI-7035.)
//
// Luckily, the constrParamAccessors are still sorted properly, so sort the field-accessors using them
// (need to undo name-mangling, including the sneaky trailing whitespace)
//
// The slightly more principled approach of using the paramss of the
// primary constructor leads to cycles in, for example, pos/t5084.scala.
val primaryNames = constrParamAccessors.map(acc => nme.dropLocalSuffix(acc.name))
caseFieldAccessorsUnsorted.sortBy { acc =>
primaryNames indexWhere { orig =>
(acc.name == orig) || (acc.name startsWith (orig append "$"))
}
}
}
private final def caseFieldAccessorsUnsorted: List[Symbol] =
(info.decls filter (_.isCaseAccessorMethod)).toList
final def constrParamAccessors: List[Symbol] =
info.decls.filter(sym => !sym.isMethod && sym.isParamAccessor).toList
/** The symbol accessed by this accessor (getter or setter) function. */
final def accessed: Symbol = accessed(owner.info)
/** The symbol accessed by this accessor function, but with given owner type. */
final def accessed(ownerTp: Type): Symbol = {
assert(hasAccessorFlag, this)
ownerTp decl nme.getterToLocal(getterName.toTermName)
}
/** The module corresponding to this module class (note that this
* is not updated when a module is cloned), or NoSymbol if this is not a ModuleClass.
*/
def sourceModule: Symbol = NoSymbol
/** The implementation class of a trait. If available it will be the
* symbol with the same owner, and the name of this symbol with $class
* appended to it.
*/
final def implClass: Symbol = owner.info.decl(tpnme.implClassName(name))
/** The class that is logically an outer class of given `clazz`.
* This is the enclosing class, except for classes defined locally to constructors,
* where it is the outer class of the enclosing class.
*/
final def outerClass: Symbol =
if (owner.isClass) owner
else if (isClassLocalToConstructor) owner.enclClass.outerClass
else owner.outerClass
/** For a paramaccessor: a superclass paramaccessor for which this symbol
* is an alias, NoSymbol for all others.
*/
def alias: Symbol = NoSymbol
/** For a lazy value, its lazy accessor. NoSymbol for all others. */
def lazyAccessor: Symbol = NoSymbol
/** If this is a lazy value, the lazy accessor; otherwise this symbol. */
def lazyAccessorOrSelf: Symbol = if (isLazy) lazyAccessor else this
/** If this is an accessor, the accessed symbol. Otherwise, this symbol. */
def accessedOrSelf: Symbol = if (hasAccessorFlag) accessed else this
/** For an outer accessor: The class from which the outer originates.
* For all other symbols: NoSymbol
*/
def outerSource: Symbol = NoSymbol
/** The superclass of this class. */
def superClass: Symbol = if (info.parents.isEmpty) NoSymbol else info.parents.head.typeSymbol
def parentSymbols: List[Symbol] = info.parents map (_.typeSymbol)
/** The directly or indirectly inherited mixins of this class
* except for mixin classes inherited by the superclass. Mixin classes appear
* in linearization order.
*/
def mixinClasses: List[Symbol] = {
val sc = superClass
ancestors takeWhile (sc ne _)
}
/** All directly or indirectly inherited classes. */
def ancestors: List[Symbol] = info.baseClasses drop 1
@inline final def enclosingSuchThat(p: Symbol => Boolean): Symbol = {
var sym = this
while (sym != NoSymbol && !p(sym))
sym = sym.owner
sym
}
/** The package class containing this symbol, or NoSymbol if there
* is not one.
* TODO: formulate as enclosingSuchThat, after making sure
* we can start with current symbol rather than onwner.
* TODO: Also harmonize with enclClass, enclMethod etc.
*/
def enclosingPackageClass: Symbol = {
var sym = this.owner
while (sym != NoSymbol && !sym.isPackageClass)
sym = sym.owner
sym
}
/** The package class containing this symbol, or NoSymbol if there
* is not one. */
def enclosingRootClass: Symbol = enclosingSuchThat(_.isRoot)
/** The package containing this symbol, or NoSymbol if there
* is not one. */
def enclosingPackage: Symbol = enclosingPackageClass.companionModule
/** Return the original enclosing method of this symbol. It should return
* the same thing as enclMethod when called before lambda lift,
* but it preserves the original nesting when called afterwards.
*
* @note This method is NOT available in the presentation compiler run. The
* originalOwner map is not populated for memory considerations (the symbol
* may hang on to lazy types and in turn to whole (outdated) compilation units.
*/
def originalEnclosingMethod: Symbol = {
assert(!forInteractive, "originalOwner is not kept in presentation compiler runs.")
if (isMethod) this
else {
val owner = originalOwner.getOrElse(this, rawowner)
if (isLocalDummy) owner.enclClass.primaryConstructor
else owner.originalEnclosingMethod
}
}
/** The method or class which logically encloses the current symbol.
* If the symbol is defined in the initialization part of a template
* this is the template's primary constructor, otherwise it is
* the physically enclosing method or class.
*
* Example 1:
*
* def f() { val x = { def g() = ...; g() } }
*
* In this case the owner chain of `g` is `x`, followed by `f` and
* `g.logicallyEnclosingMember == f`.
*
* Example 2:
*
* class C {
* def = { ... }
* val x = { def g() = ...; g() } }
* }
*
* In this case the owner chain of `g` is `x`, followed by `C` but
* g.logicallyEnclosingMember is the primary constructor symbol ``
* (or, for traits: `$init`) of `C`.
*
*/
def logicallyEnclosingMember: Symbol =
if (isLocalDummy) enclClass.primaryConstructor
else if (isMethod || isClass) this
else owner.logicallyEnclosingMember
/** Kept for source compatibility with 2.9. Scala IDE for Eclipse relies on this. */
@deprecated("Use enclosingTopLevelClass", "2.10.0")
def toplevelClass: Symbol = enclosingTopLevelClass
/** The top-level class containing this symbol. */
def enclosingTopLevelClass: Symbol =
if (owner.isPackageClass) {
if (isClass) this else moduleClass
} else owner.enclosingTopLevelClass
/** Is this symbol defined in the same scope and compilation unit as `that` symbol? */
def isCoDefinedWith(that: Symbol) = (
(this.rawInfo ne NoType)
&& (this.effectiveOwner == that.effectiveOwner)
&& ( !this.effectiveOwner.isPackageClass
|| (this.sourceFile eq null)
|| (that.sourceFile eq null)
|| (this.sourceFile.path == that.sourceFile.path) // Cheap possibly wrong check, then expensive normalization
|| (this.sourceFile.canonicalPath == that.sourceFile.canonicalPath)
)
)
/** The internal representation of classes and objects:
*
* class Foo is "the class" or sometimes "the plain class"
* object Foo is "the module"
* class Foo$ is "the module class" (invisible to the user: it implements object Foo)
*
* class Foo <
* ^ ^ (2) \
* | | | \
* | (5) | (3)
* | | | \
* (1) v v \
* object Foo (4)-> > class Foo$
*
* (1) companionClass
* (2) companionModule
* (3) linkedClassOfClass
* (4) moduleClass
* (5) companionSymbol
*/
/** For a module: the class with the same name in the same package.
* For all others: NoSymbol
* Note: does not work for classes owned by methods, see Namers.companionClassOf
*
* object Foo . companionClass --> class Foo
*
* !!! linkedClassOfClass depends on companionClass on the module class getting
* to the class. As presently implemented this potentially returns class for
* any symbol except NoSymbol.
*/
def companionClass: Symbol = flatOwnerInfo.decl(name.toTypeName).suchThat(_ isCoDefinedWith this)
/** For a class: the module or case class factory with the same name in the same package.
* For all others: NoSymbol
* Note: does not work for modules owned by methods, see Namers.companionModuleOf
*
* class Foo . companionModule --> object Foo
*/
def companionModule: Symbol = NoSymbol
/** For a module: its linked class
* For a plain class: its linked module or case factory.
* Note: does not work for modules owned by methods, see Namers.companionSymbolOf
*
* class Foo <-- companionSymbol --> object Foo
*/
def companionSymbol: Symbol = NoSymbol
/** For a module class: its linked class
* For a plain class: the module class of its linked module.
*
* class Foo <-- linkedClassOfClass --> class Foo$
*/
def linkedClassOfClass: Symbol = NoSymbol
/**
* Returns the rawInfo of the owner. If the current phase has flat classes,
* it first applies all pending type maps to this symbol.
*
* assume this is the ModuleSymbol for B in the following definition:
* package p { class A { object B { val x = 1 } } }
*
* The owner after flatten is "package p" (see "def owner"). The flatten type map enters
* symbol B in the decls of p. So to find a linked symbol ("object B" or "class B")
* we need to apply flatten to B first. Fixes #2470.
*/
protected final def flatOwnerInfo: Type = {
if (needsFlatClasses)
info
owner.rawInfo
}
/** If this symbol is an implementation class, its interface, otherwise the symbol itself
* The method follows two strategies to determine the interface.
* - during or after erasure, it takes the last parent of the implementation class
* (which is always the interface, by convention)
* - before erasure, it looks up the interface name in the scope of the owner of the class.
* This only works for implementation classes owned by other classes or traits.
* !!! Why?
*/
def toInterface: Symbol = this
/** The module class corresponding to this module.
*/
def moduleClass: Symbol = NoSymbol
/** The non-private symbol whose type matches the type of this symbol
* in in given class.
*
* @param ofclazz The class containing the symbol's definition
* @param site The base type from which member types are computed
*/
final def matchingSymbol(ofclazz: Symbol, site: Type): Symbol = {
//OPT cut down on #closures by special casing non-overloaded case
// was: ofclazz.info.nonPrivateDecl(name) filter (sym =>
// !sym.isTerm || (site.memberType(this) matches site.memberType(sym)))
val result = ofclazz.info.nonPrivateDecl(name)
def qualifies(sym: Symbol) = !sym.isTerm || (site.memberType(this) matches site.memberType(sym))
if ((result eq NoSymbol) || !result.isOverloaded && qualifies(result)) result
else result filter qualifies
}
/** The non-private member of `site` whose type and name match the type of this symbol. */
final def matchingSymbol(site: Type, admit: Long = 0L): Symbol =
site.nonPrivateMemberAdmitting(name, admit).filter(sym =>
!sym.isTerm || (site.memberType(this) matches site.memberType(sym)))
/** The symbol, in class `ofclazz`, that is overridden by this symbol.
*
* @param ofclazz is a base class of this symbol's owner.
*/
final def overriddenSymbol(ofclazz: Symbol): Symbol =
if (isClassConstructor) NoSymbol else matchingSymbol(ofclazz, owner.thisType)
/** The symbol overriding this symbol in given subclass `ofclazz`.
*
* @param ofclazz is a subclass of this symbol's owner
*/
final def overridingSymbol(ofclazz: Symbol): Symbol =
if (isClassConstructor) NoSymbol else matchingSymbol(ofclazz, ofclazz.thisType)
/** Returns all symbols overriden by this symbol. */
final def allOverriddenSymbols: List[Symbol] =
if (!owner.isClass) Nil
else owner.ancestors map overriddenSymbol filter (_ != NoSymbol)
/** Equivalent to allOverriddenSymbols.nonEmpty, but more efficient. */
// !!! When if ever will this answer differ from .isOverride?
// How/where is the OVERRIDE flag managed, as compared to how checks
// based on type membership will evaluate?
def isOverridingSymbol = owner.isClass && (
owner.ancestors exists (cls => matchingSymbol(cls, owner.thisType) != NoSymbol)
)
/** Equivalent to allOverriddenSymbols.head (or NoSymbol if no overrides) but more efficient. */
def nextOverriddenSymbol: Symbol = {
if (owner.isClass) owner.ancestors foreach { base =>
val sym = overriddenSymbol(base)
if (sym != NoSymbol)
return sym
}
NoSymbol
}
/** Returns all symbols overridden by this symbol, plus all matching symbols
* defined in parents of the selftype.
*/
final def extendedOverriddenSymbols: List[Symbol] =
if (!owner.isClass) Nil
else owner.thisSym.ancestors map overriddenSymbol filter (_ != NoSymbol)
/** The symbol accessed by a super in the definition of this symbol when
* seen from class `base`. This symbol is always concrete.
* pre: `this.owner` is in the base class sequence of `base`.
*/
final def superSymbol(base: Symbol): Symbol = {
var bcs = base.info.baseClasses.dropWhile(owner != _).tail
var sym: Symbol = NoSymbol
while (!bcs.isEmpty && sym == NoSymbol) {
if (!bcs.head.isImplClass)
sym = matchingSymbol(bcs.head, base.thisType).suchThat(!_.isDeferred)
bcs = bcs.tail
}
sym
}
/** The getter of this value or setter definition in class `base`, or NoSymbol if
* none exists.
*/
final def getter(base: Symbol): Symbol = base.info.decl(getterName) filter (_.hasAccessorFlag)
def getterName: TermName = (
if (isSetter) nme.setterToGetter(name.toTermName)
else if (nme.isLocalName(name)) nme.localToGetter(name.toTermName)
else name.toTermName
)
/** The setter of this value or getter definition, or NoSymbol if none exists */
final def setter(base: Symbol): Symbol = setter(base, false)
final def setter(base: Symbol, hasExpandedName: Boolean): Symbol = {
var sname = nme.getterToSetter(nme.getterName(name.toTermName))
if (hasExpandedName) sname = nme.expandedSetterName(sname, base)
base.info.decl(sname) filter (_.hasAccessorFlag)
}
/** If this is a derived value class, return its unbox method
* or NoSymbol if it does not exist.
*/
def derivedValueClassUnbox: Symbol = NoSymbol
/** The case module corresponding to this case class
* @pre case class is a member of some other class or package
*/
final def caseModule: Symbol = {
var modname = name.toTermName
if (privateWithin.isClass && !privateWithin.isModuleClass && !hasFlag(EXPANDEDNAME))
modname = nme.expandedName(modname, privateWithin)
initialize.owner.info.decl(modname).suchThat(_.isModule)
}
/** If this symbol is a type parameter skolem (not an existential skolem!)
* its corresponding type parameter, otherwise this */
def deSkolemize: Symbol = this
/** If this symbol is an existential skolem the location (a Tree or null)
* where it was unpacked. Resulttype is AnyRef because trees are not visible here. */
def unpackLocation: AnyRef = null
/** Remove private modifier from symbol `sym`s definition. If `sym` is a
* is not a constructor nor a static module rename it by expanding its name to avoid name clashes
* @param base the fully qualified name of this class will be appended if name expansion is needed
*/
final def makeNotPrivate(base: Symbol) {
if (this.isPrivate) {
setFlag(notPRIVATE)
// Marking these methods final causes problems for proxies which use subclassing. If people
// write their code with no usage of final, we probably shouldn't introduce it ourselves
// unless we know it is safe. ... Unfortunately if they aren't marked final the inliner
// thinks it can't inline them. So once again marking lateFINAL, and in genjvm we no longer
// generate ACC_FINAL on "final" methods which are actually lateFINAL.
if (isMethod && !isDeferred)
setFlag(lateFINAL)
if (!isStaticModule && !isClassConstructor) {
expandName(base)
if (isModule) moduleClass.makeNotPrivate(base)
}
}
}
/** Remove any access boundary and clear flags PROTECTED | PRIVATE.
*/
def makePublic = this setPrivateWithin NoSymbol resetFlag AccessFlags
/** The first parameter to the first argument list of this method,
* or NoSymbol if inapplicable.
*/
def firstParam = info.params match {
case p :: _ => p
case _ => NoSymbol
}
/* code for fixing nested objects
def expandModuleClassName() {
name = newTypeName(name.toString + "$")
}
def isExpandedModuleClass: Boolean = name(name.length - 1) == '$'
*/
/** Desire to re-use the field in ClassSymbol which stores the source
* file to also store the classfile, but without changing the behavior
* of sourceFile (which is expected at least in the IDE only to
* return actual source code.) So sourceFile has classfiles filtered out.
*/
private def sourceFileOnly(file: AbstractFile): AbstractFile =
if ((file eq null) || (file.path endsWith ".class")) null else file
private def binaryFileOnly(file: AbstractFile): AbstractFile =
if ((file eq null) || !(file.path endsWith ".class")) null else file
final def binaryFile: AbstractFile = binaryFileOnly(associatedFile)
final def sourceFile: AbstractFile = sourceFileOnly(associatedFile)
/** Overridden in ModuleSymbols to delegate to the module class. */
def associatedFile: AbstractFile = enclosingTopLevelClass.associatedFile
def associatedFile_=(f: AbstractFile) { abort("associatedFile_= inapplicable for " + this) }
@deprecated("Use associatedFile_= instead", "2.10.0")
def sourceFile_=(f: AbstractFile): Unit = associatedFile_=(f)
/** If this is a sealed class, its known direct subclasses.
* Otherwise, the empty set.
*/
def children: Set[Symbol] = Set()
/** Recursively assemble all children of this symbol.
*/
def sealedDescendants: Set[Symbol] = children.flatMap(_.sealedDescendants) + this
@inline final def orElse(alt: => Symbol): Symbol = if (this ne NoSymbol) this else alt
@inline final def andAlso(f: Symbol => Unit): Symbol = { if (this ne NoSymbol) f(this) ; this }
// ------ toString -------------------------------------------------------------------
/** A tag which (in the ideal case) uniquely identifies class symbols */
final def tag: Int = fullName.##
/** The simple name of this Symbol */
final def simpleName: Name = name
/** The String used to order otherwise identical sealed symbols.
* This uses data which is stable across runs and variable classpaths
* (the initial Name) before falling back on id, which varies depending
* on exactly when a symbol is loaded.
*/
final def sealedSortName: String = initName + "#" + id
/** String representation of symbol's definition key word */
final def keyString: String =
if (isJavaInterface) "interface"
else if (isTrait && !isImplClass) "trait"
else if (isClass) "class"
else if (isType && !isParameter) "type"
else if (isVariable) "var"
else if (isPackage) "package"
else if (isModule) "object"
else if (isSourceMethod) "def"
else if (isTerm && (!isParameter || isParamAccessor)) "val"
else ""
private case class SymbolKind(accurate: String, sanitized: String, abbreviation: String)
private def symbolKind: SymbolKind = {
var kind =
if (isTermMacro) ("macro method", "macro method", "MAC")
else if (isInstanceOf[FreeTermSymbol]) ("free term", "free term", "FTE")
else if (isInstanceOf[FreeTypeSymbol]) ("free type", "free type", "FTY")
else if (isPackage) ("package", "package", "PK")
else if (isPackageClass) ("package class", "package", "PKC")
else if (isPackageObject) ("package object", "package", "PKO")
else if (isPackageObjectClass) ("package object class", "package", "PKOC")
else if (isAnonymousClass) ("anonymous class", "anonymous class", "AC")
else if (isRefinementClass) ("refinement class", "", "RC")
else if (isModule) ("module", "object", "MOD")
else if (isModuleClass) ("module class", "object", "MODC")
else if (isGetter) ("getter", if (isSourceMethod) "method" else "value", "GET")
else if (isSetter) ("setter", if (isSourceMethod) "method" else "value", "SET")
else if (isTerm && isLazy) ("lazy value", "lazy value", "LAZ")
else if (isVariable) ("field", "variable", "VAR")
else if (isImplClass) ("implementation class", "class", "IMPL")
else if (isTrait) ("trait", "trait", "TRT")
else if (isClass) ("class", "class", "CLS")
else if (isType) ("type", "type", "TPE")
else if (isClassConstructor && isPrimaryConstructor) ("primary constructor", "constructor", "PCTOR")
else if (isClassConstructor) ("constructor", "constructor", "CTOR")
else if (isSourceMethod) ("method", "method", "METH")
else if (isTerm) ("value", "value", "VAL")
else ("", "", "???")
if (isSkolem) kind = (kind._1, kind._2, kind._3 + "#SKO")
SymbolKind(kind._1, kind._2, kind._3)
}
/** Accurate string representation of symbols' kind, suitable for developers. */
final def accurateKindString: String =
symbolKind.accurate
/** String representation of symbol's kind, suitable for the masses. */
private def sanitizedKindString: String =
symbolKind.sanitized
/** String representation of symbol's kind, suitable for the masses. */
protected[scala] def abbreviatedKindString: String =
symbolKind.abbreviation
final def kindString: String =
if (settings.debug.value) accurateKindString
else sanitizedKindString
/** If the name of the symbol's owner should be used when you care about
* seeing an interesting name: in such cases this symbol is e.g. a method
* parameter with a synthetic name, a constructor named "this", an object
* "package", etc. The kind string, if non-empty, will be phrased relative
* to the name of the owner.
*/
def hasMeaninglessName = (
isSetterParameter // x$1
|| isClassConstructor // this
|| isRefinementClass //
|| (name == nme.PACKAGE) // package
)
/** String representation of symbol's simple name.
* If !settings.debug translates expansions of operators back to operator symbol.
* E.g. $eq => =.
* If settings.uniqid, adds id.
* If settings.Yshowsymkinds, adds abbreviated symbol kind.
*/
def nameString: String = (
if (!settings.uniqid.value && !settings.Yshowsymkinds.value) "" + originalName.decode
else if (settings.uniqid.value && !settings.Yshowsymkinds.value) originalName.decode + "#" + id
else if (!settings.uniqid.value && settings.Yshowsymkinds.value) originalName.decode + "#" + abbreviatedKindString
else originalName.decode + "#" + id + "#" + abbreviatedKindString
)
def fullNameString: String = {
def recur(sym: Symbol): String = {
if (sym.isRootSymbol || sym == NoSymbol) sym.nameString
else if (sym.owner.isEffectiveRoot) sym.nameString
else recur(sym.effectiveOwner.enclClass) + "." + sym.nameString
}
recur(this)
}
/** If settings.uniqid is set, the symbol's id, else "" */
final def idString = if (settings.uniqid.value) "#"+id else ""
/** String representation, including symbol's kind e.g., "class Foo", "method Bar".
* If hasMeaninglessName is true, uses the owner's name to disambiguate identity.
*/
override def toString: String = compose(
kindString,
if (hasMeaninglessName) owner.decodedName + idString else nameString
)
/** String representation of location.
*/
def ownsString: String = {
val owns = effectiveOwner
if (owns.isClass && !owns.isEmptyPrefix) "" + owns else ""
}
/** String representation of location, plus a preposition. Doesn't do much,
* for backward compatibility reasons.
*/
def locationString: String = ownsString match {
case "" => ""
case s => " in " + s
}
def fullLocationString: String = toString + locationString
def signatureString: String = if (hasRawInfo) infoString(rawInfo) else "<_>"
/** String representation of symbol's definition following its name */
final def infoString(tp: Type): String = {
def parents = (
if (settings.debug.value) parentsString(tp.parents)
else briefParentsString(tp.parents)
)
if (isType) typeParamsString(tp) + (
if (isClass) " extends " + parents
else if (isAliasType) " = " + tp.resultType
else tp.resultType match {
case rt @ TypeBounds(_, _) => "" + rt
case rt => " <: " + rt
}
)
else if (isModule) "" // avoid "object X of type X.type"
else tp match {
case PolyType(tparams, res) => typeParamsString(tp) + infoString(res)
case NullaryMethodType(res) => infoString(res)
case MethodType(params, res) => valueParamsString(tp) + infoString(res)
case _ => ": " + tp
}
}
def infosString = infos.toString
def debugLocationString = fullLocationString + " (flags: " + debugFlagString + ")"
private def defStringCompose(infoString: String) = compose(
flagString,
keyString,
varianceString + nameString + infoString + flagsExplanationString
)
/** String representation of symbol's definition. It uses the
* symbol's raw info to avoid forcing types.
*/
def defString = defStringCompose(signatureString)
/** String representation of symbol's definition, using the supplied
* info rather than the symbol's.
*/
def defStringSeenAs(info: Type) = defStringCompose(infoString(info))
/** Concatenate strings separated by spaces */
private def compose(ss: String*) = ss filter (_ != "") mkString " "
def isSingletonExistential =
nme.isSingletonName(name) && (info.bounds.hi.typeSymbol isSubClass SingletonClass)
/** String representation of existentially bound variable */
def existentialToString =
if (isSingletonExistential && !settings.debug.value)
"val " + tpnme.dropSingletonName(name) + ": " + dropSingletonType(info.bounds.hi)
else defString
}
implicit val SymbolTag = ClassTag[Symbol](classOf[Symbol])
/** A class for term symbols */
class TermSymbol protected[Symbols] (initOwner: Symbol, initPos: Position, initName: TermName)
extends Symbol(initOwner, initPos, initName) with TermSymbolApi {
private[this] var _referenced: Symbol = NoSymbol
privateWithin = NoSymbol
type TypeOfClonedSymbol = TermSymbol
private[this] var _rawname: TermName = initName
def rawname = _rawname
def name = {
if (Statistics.hotEnabled) Statistics.incCounter(nameCount)
_rawname
}
override def name_=(name: Name) {
if (name != rawname) {
super.name_=(name) // logging
changeNameInOwners(name)
_rawname = name.toTermName
}
}
final def asNameType(n: Name) = n.toTermName
/** Term symbols with the exception of static parts of Java classes and packages.
*/
override def isValue = !(isModule && hasFlag(PACKAGE | JAVA))
override def isVariable = isMutable && !isMethod
override def isTermMacro = hasFlag(MACRO)
// interesting only for lambda lift. Captured variables are accessed from inner lambdas.
override def isCapturedVariable = hasAllFlags(MUTABLE | CAPTURED) && !hasFlag(METHOD)
override def companionSymbol: Symbol = companionClass
override def moduleClass = if (isModule) referenced else NoSymbol
override def hasDefault = this hasFlag DEFAULTPARAM // overloaded with TRAIT
override def isBridge = this hasFlag BRIDGE
override def isEarlyInitialized = this hasFlag PRESUPER
override def isMethod = this hasFlag METHOD
override def isModule = this hasFlag MODULE
override def isOverloaded = this hasFlag OVERLOADED
override def isPackage = this hasFlag PACKAGE
override def isValueParameter = this hasFlag PARAM
override def isSetterParameter = isValueParameter && owner.isSetter
override def isAccessor = this hasFlag ACCESSOR
override def isGetter = isAccessor && !isSetter
override def isSetter = isAccessor && nme.isSetterName(name) // todo: make independent of name, as this can be forged.
override def isLocalDummy = nme.isLocalDummyName(name)
override def isClassConstructor = name == nme.CONSTRUCTOR
override def isMixinConstructor = name == nme.MIXIN_CONSTRUCTOR
override def isConstructor = nme.isConstructorName(name)
override def isPackageObject = isModule && (name == nme.PACKAGE)
override def isStable = !isUnstable
private def isUnstable = (
isMutable
|| (hasFlag(METHOD | BYNAMEPARAM) && !hasFlag(STABLE))
|| (tpe.isVolatile && !hasAnnotation(uncheckedStableClass))
)
// The name in comments is what it is being disambiguated from.
// TODO - rescue CAPTURED from BYNAMEPARAM so we can see all the names.
override def resolveOverloadedFlag(flag: Long) = flag match {
case DEFAULTPARAM => "" // TRAIT
case MIXEDIN => "" // EXISTENTIAL
case LABEL => "