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|
/* NSC -- new Scala compiler
* Copyright 2005-2007 LAMP/EPFL
* @author Martin Odersky
*/
// $Id$
package scala.tools.nsc.symtab
import scala.tools.nsc.io.AbstractFile
import scala.tools.nsc.util.{Position, NoPosition, SourceFile}
import Flags._
trait Symbols {
self: SymbolTable =>
import definitions._
private var ids = 0
//for statistics:
def symbolCount = ids
var typeSymbolCount = 0
var classSymbolCount = 0
val emptySymbolArray = new Array[Symbol](0)
val emptySymbolSet = Set.empty[Symbol]
/*
type Position;
def NoPos : Position;
def FirstPos : Position;
implicit def coercePosToInt(pos : Position) : Int;
def coerceIntToPos(pos : Int) : Position;
object RequiresIntsAsPositions {
implicit def coerceIntToPos0(pos: Int) =
coerceIntToPos(pos)
}
*/
/** The class for all symbols */
abstract class Symbol(initOwner: Symbol, initPos: Position, initName: Name) {
var rawowner = initOwner
var rawname = initName
var rawflags: Long = 0
private var rawpos = initPos
val id = { ids += 1; ids }
// assert(id != 6935, initName)
var validTo: Period = NoPeriod
def pos = rawpos
def setPos(pos: Position): this.type = { this.rawpos = pos; this }
def namePos(source: SourceFile) = {
val pos: Int = this.pos.offset.get(-1)
val buf = source.content
if (pos == -1) -1
else if (isTypeParameter) pos - name.length
else if (isVariable || isMethod || isClass || isModule) {
var ret = pos
if (buf(pos) == ',') ret += 1
else if (isClass) ret += "class".length()
else if (isModule) ret += "object".length()
else ret += "var".length()
while (buf(ret).isWhitespace) ret += 1
ret
}
else if (isValue) {
if (pos < (buf.length + ("val ").length())) {
if ((buf(pos + 0) == 'v') &&
(buf(pos + 1) == 'a') &&
(buf(pos + 2) == 'l') &&
(buf(pos + 3) == ' ')) {
var pos0 = pos + 4
while (pos0 < buf.length && buf(pos0).isWhitespace)
pos0 += 1
pos0
} else pos
} else pos
}
else -1
}
var attributes: List[AnnotationInfo] = List()
/** Does this symbol have an attribute of the given class? */
def hasAttribute(cls: Symbol): Boolean =
attributes.exists {
case AnnotationInfo(tp, _, _) if tp.typeSymbol == cls => true
case _ => false
}
var privateWithin: Symbol = _
// Creators -------------------------------------------------------------------
final def newValue(pos: Position, name: Name) =
new TermSymbol(this, pos, name)
final def newVariable(pos: Position, name: Name) =
newValue(pos, name).setFlag(MUTABLE)
final def newValueParameter(pos: Position, name: Name) =
newValue(pos, name).setFlag(PARAM)
final def newLocalDummy(pos: Position) =
newValue(pos, nme.LOCAL(this)).setInfo(NoType)
final def newMethod(pos: Position, name: Name) =
newValue(pos, name).setFlag(METHOD)
final def newLabel(pos: Position, name: Name) =
newMethod(pos, name).setFlag(LABEL)
final def newConstructor(pos: Position) =
newMethod(pos, nme.CONSTRUCTOR)
final def newModule(pos: Position, name: Name, clazz: ClassSymbol) =
new ModuleSymbol(this, pos, name).setFlag(MODULE | FINAL)
.setModuleClass(clazz)
final def newModule(pos: Position, name: Name) = {
val m = new ModuleSymbol(this, pos, name).setFlag(MODULE | FINAL)
m.setModuleClass(new ModuleClassSymbol(m))
}
final def newPackage(pos: Position, name: Name) = {
assert(name == nme.ROOT || isPackageClass)
val m = newModule(pos, name).setFlag(JAVA | PACKAGE)
m.moduleClass.setFlag(JAVA | PACKAGE)
m
}
final def newThisSym(pos: Position) =
newValue(pos, nme.this_).setFlag(SYNTHETIC)
final def newImport(pos: Position) =
newValue(pos, nme.IMPORT)
final def newOverloaded(pre: Type, alternatives: List[Symbol]): Symbol =
newValue(alternatives.head.pos, alternatives.head.name)
.setFlag(OVERLOADED)
.setInfo(OverloadedType(pre, alternatives))
final def newOuterAccessor(pos: Position) = {
val sym = newMethod(pos, nme.OUTER)
sym setFlag (STABLE | SYNTHETIC)
if (isTrait) sym setFlag DEFERRED
sym.expandName(this)
sym.referenced = this
sym
}
final def newErrorValue(name: Name) =
newValue(pos, name).setFlag(SYNTHETIC | IS_ERROR).setInfo(ErrorType)
final def newAliasType(pos: Position, name: Name) =
new TypeSymbol(this, pos, name)
final def newAbstractType(pos: Position, name: Name) =
new TypeSymbol(this, pos, name).setFlag(DEFERRED)
final def newTypeParameter(pos: Position, name: Name) =
newAbstractType(pos, name).setFlag(PARAM)
final def newTypeSkolem: Symbol =
new TypeSkolem(owner, pos, name, this)
.setFlag(flags)
final def newClass(pos: Position, name: Name) =
new ClassSymbol(this, pos, name)
final def newModuleClass(pos: Position, name: Name) =
new ModuleClassSymbol(this, pos, name)
final def newAnonymousClass(pos: Position) =
newClass(pos, nme.ANON_CLASS_NAME.toTypeName)
final def newAnonymousFunctionClass(pos: Position) = {
val anonfun = newClass(pos, nme.ANON_FUN_NAME.toTypeName)
anonfun.attributes =
AnnotationInfo(definitions.SerializableAttr.tpe, List(), List()) :: anonfun.attributes
anonfun
}
final def newRefinementClass(pos: Position) =
newClass(pos, nme.REFINE_CLASS_NAME.toTypeName)
final def newErrorClass(name: Name) = {
val clazz = newClass(pos, name).setFlag(SYNTHETIC | IS_ERROR)
clazz.setInfo(ClassInfoType(List(), new ErrorScope(this), clazz))
clazz
}
final def newErrorSymbol(name: Name): Symbol =
if (name.isTypeName) newErrorClass(name) else newErrorValue(name)
// Tests ----------------------------------------------------------------------
def isTerm = false //to be overridden
def isType = false //to be overridden
def isClass = false //to be overridden
def isTypeMember = false //to be overridden
def isAliasType = false //to be overridden
def isAbstractType = false //to be overridden
def isSkolem = false //to be overridden
final def isValue = isTerm && !(isModule && hasFlag(PACKAGE | JAVA))
final def isVariable = isTerm && hasFlag(MUTABLE) && !isMethod
final def isCapturedVariable = isVariable && hasFlag(CAPTURED)
final def isGetter = isTerm && hasFlag(ACCESSOR) && !nme.isSetterName(name)
final def isSetter = isTerm && hasFlag(ACCESSOR) && nme.isSetterName(name)
//todo: make independent of name, as this can be forged.
final def hasGetter = isTerm && nme.isLocalName(name)
final def isValueParameter = isTerm && hasFlag(PARAM)
final def isLocalDummy = isTerm && nme.isLocalDummyName(name)
final def isMethod = isTerm && hasFlag(METHOD)
final def isSourceMethod = isTerm && (flags & (METHOD | STABLE)) == METHOD
final def isLabel = isTerm && hasFlag(LABEL)
final def isClassConstructor = isTerm && (name == nme.CONSTRUCTOR)
final def isMixinConstructor = isTerm && (name == nme.MIXIN_CONSTRUCTOR)
final def isConstructor = isTerm && (name == nme.CONSTRUCTOR) || (name == nme.MIXIN_CONSTRUCTOR)
final def isModule = isTerm && hasFlag(MODULE)
final def isStaticModule = isModule && isStatic && !isMethod
final def isPackage = isModule && hasFlag(PACKAGE)
final def isThisSym = isTerm && owner.thisSym == this
final def isMonomorphicType = isType && hasFlag(MONOMORPHIC)
final def isError = hasFlag(IS_ERROR)
final def isErroneous = isError || isInitialized && tpe.isErroneous
final def isTrait = isClass & hasFlag(TRAIT)
final def isTypeParameterOrSkolem = isType && hasFlag(PARAM)
final def isTypeSkolem = isSkolem && hasFlag(PARAM)
final def isTypeParameter = isTypeParameterOrSkolem && !isSkolem
final def isExistential = isType && hasFlag(EXISTENTIAL)
final def isExistentialSkolem = isSkolem && hasFlag(EXISTENTIAL)
final def isExistentialQuantified = isExistential && !isSkolem
final def isClassLocalToConstructor = isClass && hasFlag(INCONSTRUCTOR)
final def isAnonymousClass = isClass && (originalName startsWith nme.ANON_CLASS_NAME)
// startsWith necessary because name may grow when lifted and also because of anonymous function classes
final def isRefinementClass = isClass && name == nme.REFINE_CLASS_NAME.toTypeName; // no lifting for refinement classes
final def isModuleClass = isClass && hasFlag(MODULE)
final def isPackageClass = isClass && hasFlag(PACKAGE)
final def isRoot = isPackageClass && name == nme.ROOT.toTypeName
final def isRootPackage = isPackage && name == nme.ROOTPKG
final def isEmptyPackage = isPackage && name == nme.EMPTY_PACKAGE_NAME
final def isEmptyPackageClass = isPackageClass && name == nme.EMPTY_PACKAGE_NAME.toTypeName
final def isPredefModule = isModule && name == nme.Predef // not printed as a prefix
final def isScalaPackage = isPackage && name == nme.scala_ // not printed as a prefix
final def isScalaPackageClass = isPackageClass && name == nme.scala_.toTypeName // not printed as a prefix
def isDeprecated =
attributes exists (attr => attr.atp.typeSymbol == DeprecatedAttr)
/** Does this symbol denote a wrapper object of the interpreter or its class? */
final def isInterpreterWrapper =
(isModule || isModuleClass) &&
owner.isEmptyPackageClass &&
name.toString.startsWith(nme.INTERPRETER_LINE_PREFIX) &&
name.toString.endsWith(nme.INTERPRETER_WRAPPER_SUFFIX)
/** Does this symbol denote a stable value? */
final def isStable =
isTerm && !hasFlag(MUTABLE) && (!hasFlag(METHOD | BYNAMEPARAM) || hasFlag(STABLE))
/** Is this symbol a public */
final def isPublic: Boolean =
!hasFlag(PRIVATE | PROTECTED) && privateWithin == NoSymbol
/** Is this symbol a private local */
final def isPrivateLocal =
hasFlag(PRIVATE) && hasFlag(LOCAL)
/** Is this symbol a protected local */
final def isProtectedLocal =
hasFlag(PROTECTED) && hasFlag(LOCAL)
/** Does this symbol denote the primary constructor of its enclosing class? */
final def isPrimaryConstructor =
isConstructor && owner.primaryConstructor == this
/** Is this symbol a case class factory method? */
final def isCaseFactory =
isMethod && hasFlag(CASE)
/** Is this symbol an implementation class for a mixin? */
final def isImplClass: Boolean = isClass && hasFlag(IMPLCLASS)
/** Is thhis symbol early initialized */
final def isEarly: Boolean = isTerm && hasFlag(PRESUPER)
/** Is this symbol a trait which needs an implementation class? */
final def needsImplClass: Boolean =
isTrait && (!hasFlag(INTERFACE) || hasFlag(lateINTERFACE)) && !isImplClass
/** Is this a symbol which exists only in the implementation class, not in its trait? */
final def isImplOnly: Boolean =
hasFlag(PRIVATE) ||
(owner.isImplClass || owner.isTrait) &&
((hasFlag(notPRIVATE | LIFTED) && !hasFlag(ACCESSOR | SUPERACCESSOR | MODULE) || isConstructor) ||
(hasFlag(LIFTED) && isModule && isMethod))
/** Is this symbol a module variable ? */
final def isModuleVar: Boolean = isVariable && hasFlag(MODULEVAR)
/** Is this symbol static (i.e. with no outer instance)? */
final def isStatic: Boolean =
hasFlag(STATIC) || isRoot || owner.isStaticOwner
/** Does this symbol denote a class that defines static symbols? */
final def isStaticOwner: Boolean =
isPackageClass || isModuleClass && isStatic
/** Is this symbol final?*/
final def isFinal: Boolean = (
hasFlag(FINAL) ||
isTerm && (
hasFlag(PRIVATE) || isLocal || owner.isClass && owner.hasFlag(FINAL | MODULE))
)
/** Is this symbol a sealed class?*/
final def isSealed: Boolean =
isClass && (hasFlag(SEALED) || isUnboxedClass(this))
/** 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 && (tpe match {
case ConstantType(_) => true
case PolyType(_, ConstantType(_)) => true
case MethodType(_, ConstantType(_)) => true
case _ => false
})
/** Is this class nested in another class or module (not a package)? */
final def isNestedClass: Boolean =
isClass && !isRoot && !owner.isPackageClass
/** 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
*/
final def isLocalClass: Boolean =
isClass && (isAnonymousClass || isRefinementClass || isLocal ||
!owner.isPackageClass && owner.isLocalClass)
/** 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 inclomplete.
*
* @param base ...
* @return ...
*/
final def isIncompleteIn(base: Symbol): Boolean = (
(this hasFlag DEFERRED) ||
(this hasFlag ABSOVERRIDE) && {
val supersym = superSymbol(base)
supersym == NoSymbol || supersym.isIncompleteIn(base)
}
)
final def exists: Boolean =
this != NoSymbol && (!owner.isPackageClass || { rawInfo.load(this); rawInfo != NoType })
final def isInitialized: Boolean =
validTo != NoPeriod
final def isStableClass: Boolean = {
def hasNoAbstractTypeMember(clazz: Symbol): Boolean =
(clazz hasFlag STABLE) || {
var e = clazz.info.decls.elems
while ((e ne null) && !(e.sym.isAbstractType && info.member(e.sym.name) == e.sym))
e = e.next
e == null
}
def checkStable() =
(info.baseClasses forall hasNoAbstractTypeMember) && { setFlag(STABLE); true }
isClass && (hasFlag(STABLE) || checkStable())
}
final def isCovariant: Boolean = isType && hasFlag(COVARIANT)
final def isContravariant: Boolean = isType && hasFlag(CONTRAVARIANT)
/** The variance of this symbol as an integer */
final def variance: Int =
if (isCovariant) 1
else if (isContravariant) -1
else 0
// Flags, owner, and name attributes --------------------------------------------------------------
def owner: Symbol = rawowner
final def owner_=(owner: Symbol) { rawowner = owner }
def ownerChain: List[Symbol] = this :: owner.ownerChain
def name: Name = rawname
final def name_=(name: Name) {
if (name != rawname) {
if (owner.isClass) {
var ifs = owner.infos
while (ifs != null) {
ifs.info.decls.rehash(this, name)
ifs = ifs.prev
}
}
rawname = name
}
}
/** If this symbol has an expanded name, its original name, otherwise its name itself.
* @see expandName
*/
def originalName = nme.originalName(name)
final def flags: Long = {
val fs = rawflags & phase.flagMask
(fs | ((fs & LateFlags) >>> LateShift)) & ~(fs >>> AntiShift)
}
final def flags_=(fs: Long) = rawflags = fs
final def setFlag(mask: Long): this.type = { rawflags = rawflags | mask; this }
final def resetFlag(mask: Long): this.type = { rawflags = rawflags & ~mask; this }
final def getFlag(mask: Long): Long = flags & mask
final def hasFlag(mask: Long): Boolean = (flags & mask) != 0
final def resetFlags { rawflags = rawflags & TopLevelCreationFlags }
/** The class or term up to which this symbol is accessible,
* or RootClass if it is public
*/
def accessBoundary(base: Symbol): Symbol = {
if (hasFlag(PRIVATE) || owner.isTerm) owner
else if (privateWithin != NoSymbol && !phase.erasedTypes) privateWithin
else if (hasFlag(PROTECTED)) base
else RootClass
}
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
}
// Info and Type -------------------------------------------------------------------
private[Symbols] var infos: TypeHistory = null
/** Get type. The type of a symbol is:
* for a type symbol, the type corresponding to the symbol itself
* for a term symbol, its usual type
*/
def tpe: Type = info
/** Get type info associated with symbol at current phase, after
* ensuring that symbol is initialized (i.e. type is completed).
*/
def info: Type = {
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) != 0) {
setInfo(ErrorType)
throw CyclicReference(this, tp)
}
rawflags = rawflags | LOCKED
val current = phase
try {
phase = phaseOf(infos.validFrom)
tp.complete(this)
// if (settings.debug.value && runId(validTo) == currentRunId) System.out.println("completed " + this/* + ":" + info*/);//DEBUG
rawflags = rawflags & ~LOCKED
} finally {
phase = current
}
cnt += 1
// allow for two completions:
// one: sourceCompleter to LazyType, two: LazyType to completed type
if (cnt == 3) throw new Error("no progress in completing " + this + ":" + tp)
}
val result = rawInfo
result
}
/** Set initial info. */
def setInfo(info: Type): this.type = {
assert(info ne null)
infos = TypeHistory(currentPeriod, info, null)
if (info.isComplete) {
rawflags = rawflags & ~LOCKED
validTo = currentPeriod
} else {
rawflags = rawflags & ~LOCKED
validTo = NoPeriod
}
this
}
/** Set new info valid from start of this phase. */
final def updateInfo(info: Type): Symbol = {
assert(phaseId(infos.validFrom) <= phase.id)
if (phaseId(infos.validFrom) == phase.id) infos = infos.prev
infos = TypeHistory(currentPeriod, info, infos)
this
}
/** Return info without checking for initialization or completing */
def rawInfo: Type = {
var infos = this.infos
assert(infos != null, name)
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) {
// 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
}
private def adaptInfos(infos: TypeHistory): TypeHistory =
if (infos == null || runId(infos.validFrom) == currentRunId) {
infos
} else {
val prev1 = adaptInfos(infos.prev)
if (prev1 ne infos.prev) prev1
else {
def adaptToNewRun(info: Type): Type =
if (isPackageClass) info else adaptToNewRunMap(info)
val pid = phaseId(infos.validFrom)
validTo = period(currentRunId, pid)
phase = phaseWithId(pid)
val info1 = adaptToNewRun(infos.info)
if (info1 eq infos.info) {
infos.validFrom = validTo
infos
} else {
this.infos = TypeHistory(validTo, info1, prev1)
this.infos
}
}
}
/** Initialize the symbol */
final def initialize: this.type = {
if (!isInitialized) info
this
}
/** Was symbol's type updated during given phase? */
final def isUpdatedAt(pid: Phase#Id): Boolean = {
var infos = this.infos
while ((infos ne null) && phaseId(infos.validFrom) != pid + 1) infos = infos.prev
infos ne null
}
/** 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 =
throw new Error("typeConstructor inapplicable for " + this)
def tpeHK = if(isType) typeConstructor else tpe // @M! used in memberType
/** The type parameters of this symbol */
def unsafeTypeParams: List[Symbol] =
if (isMonomorphicType) List() else rawInfo.typeParams
/*
val limit = phaseId(validTo)
(if (limit < phase.id) infos.info else rawInfo).typeParams
*/
def typeParams: List[Symbol] =
if (isMonomorphicType) List() else { rawInfo.load(this); rawInfo.typeParams }
def getAttributes(clazz: Symbol): List[AnnotationInfo] =
attributes.filter(_.atp.typeSymbol.isNonBottomSubClass(clazz))
/** Reset symbol to initial state
*/
def reset(completer: Type) {
resetFlags
infos = null
validTo = NoPeriod
//limit = NoPhase.id
setInfo(completer)
}
// 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, -|closure| for type symbols, id)
*/
final def isLess(that: Symbol): Boolean = {
def closureLength(sym: Symbol) =
if (sym.isAbstractType) 1 + sym.info.bounds.hi.closure.length
else sym.info.closure.length
if (this.isType)
(that.isType &&
{ val diff = closureLength(this) - closureLength(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? */
final def isNonBottomSubClass(that: Symbol): Boolean =
this == that || this.isError || that.isError ||
info.closurePos(that) >= 0
final def isSubClass(that: Symbol): Boolean = {
isNonBottomSubClass(that) ||
this == AllClass ||
this == AllRefClass &&
(that == AnyClass ||
that != AllClass && (that isSubClass AnyRefClass))
}
// Overloaded Alternatives ---------------------------------------------------------
def alternatives: List[Symbol] =
if (hasFlag(OVERLOADED)) info.asInstanceOf[OverloadedType].alternatives
else List(this)
def filter(cond: Symbol => Boolean): Symbol =
if (hasFlag(OVERLOADED)) {
//assert(info.isInstanceOf[OverloadedType], "" + this + ":" + info);//DEBUG
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 hasFlag OVERLOADED), result.alternatives)
result
}
// Cloneing -------------------------------------------------------------------
/** A clone of this symbol */
final def cloneSymbol: Symbol =
cloneSymbol(owner)
/** A clone of this symbol, but with given owner */
final def cloneSymbol(owner: Symbol): Symbol =
cloneSymbolImpl(owner).setInfo(info.cloneInfo(owner)).setFlag(this.rawflags)
/** Internal method to clone a symbol's implementation without flags or type
*/
def cloneSymbolImpl(owner: Symbol): Symbol
// 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 = {
val c = info.decl(
if (isTrait || isImplClass) nme.MIXIN_CONSTRUCTOR
else nme.CONSTRUCTOR)
if (c hasFlag OVERLOADED) c.alternatives.head else c
}
/** The self symbol of a class with explicit self type, or else the
* symbol itself.
*/
def thisSym: Symbol = this
/** The type of `this' in a class, or else the type of the symbol itself. */
def typeOfThis = thisSym.tpe
/** Sets the type of `this' in a class */
def typeOfThis_=(tp: Type): Unit =
throw new Error("typeOfThis cannot be set for " + this)
/** If symbol is a class, the type <code>this.type</code> in this class,
* otherwise <code>NoPrefix</code>.
*/
def thisType: Type = NoPrefix
/** Return every accessor of a primary constructor parameter in this case class
*/
final def caseFieldAccessors: List[Symbol] =
info.decls.toList filter (sym => !(sym hasFlag PRIVATE) && sym.hasFlag(CASEACCESSOR))
final def constrParamAccessors: List[Symbol] =
info.decls.toList filter (sym => !sym.isMethod && sym.hasFlag(PARAMACCESSOR))
/** The symbol accessed by this accessor function.
*/
final def accessed: Symbol = {
assert(hasFlag(ACCESSOR))
owner.info.decl(nme.getterToLocal(if (isSetter) nme.setterToGetter(name) else name))
}
/** The implementation class of a trait */
final def implClass: Symbol = owner.info.decl(nme.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, it's lazy accessor. NoSymbol for all others */
def lazyAccessor: Symbol = NoSymbol
/** 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
/** The directly or indirectly inherited mixins of this class
* except for mixin classes inherited by the superclass. Mixin classes appear
* in linearlization order.
*/
def mixinClasses: List[Symbol] = {
val sc = superClass
info.baseClasses.tail.takeWhile(sc ne)
}
/** The top-level class containing this symbol */
def toplevelClass: Symbol =
if (owner.isPackageClass) {
if (isClass) this else moduleClass
} else owner.toplevelClass
/** The class with the same name in the same package as this module or
* case class factory
*/
final def linkedClassOfModule: Symbol = {
if (this != NoSymbol)
owner.info.decl(name.toTypeName).suchThat(sym => sym.rawInfo ne NoType)
else NoSymbol
}
/** The module or case class factory with the same name in the same
* package as this class.
*/
final def linkedModuleOfClass: Symbol =
if (this.isClass && !this.isAnonymousClass && !this.isRefinementClass) {
owner.rawInfo.decl(name.toTermName).suchThat(
sym => (sym hasFlag MODULE) && (sym.rawInfo ne NoType))
} else NoSymbol
/** For a module its linked class, for a class its linked module or case
* factory otherwise.
*/
final def linkedSym: Symbol =
if (isTerm) linkedClassOfModule
else if (isClass) owner.info.decl(name.toTermName).suchThat(sym => sym.rawInfo ne NoType)
else NoSymbol
/** For a module class its linked class, for a plain class
* the module class of its linked module.
*/
final def linkedClassOfClass: Symbol =
if (isModuleClass) linkedClassOfModule else linkedModuleOfClass.moduleClass
/** 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 implementatation 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.
*/
final def toInterface: Symbol =
if (isImplClass) {
val result =
if (phase.next.erasedTypes) {
assert(!tpe.parents.isEmpty, this)
tpe.parents.last.typeSymbol
} else {
owner.info.decl(nme.interfaceName(name))
}
assert(result != NoSymbol, this)
result
} else this
/** The module corresponding to this module class (note that this
* is not updated when a module is cloned).
*/
def sourceModule: Symbol = NoSymbol
/** 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 =
ofclazz.info.nonPrivateDecl(name).filter(sym =>
!sym.isTerm || (site.memberType(this) matches site.memberType(sym)))
/** The non-private member of `site' whose type and name match the type of this symbol
*/
final def matchingSymbol(site: Type): Symbol =
site.nonPrivateMember(name).filter(sym =>
!sym.isTerm || (site.memberType(this) matches site.memberType(sym)))
/** The symbol overridden by this symbol in given class `ofclazz' */
final def overriddenSymbol(ofclazz: Symbol): Symbol =
matchingSymbol(ofclazz, owner.thisType)
/** The symbol overriding this symbol in given subclass `ofclazz' */
final def overridingSymbol(ofclazz: Symbol): Symbol =
matchingSymbol(ofclazz, ofclazz.thisType)
final def allOverriddenSymbols: List[Symbol] =
if (owner.isClass && !owner.info.baseClasses.isEmpty)
for { bc <- owner.info.baseClasses.tail
val s = overriddenSymbol(bc)
if s != NoSymbol } yield s
else List()
/** 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(
sym => !sym.hasFlag(DEFERRED))
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 = {
val getterName = if (isSetter) nme.setterToGetter(name) else nme.getterName(name)
base.info.decl(getterName) filter (_.hasFlag(ACCESSOR))
}
/** The setter of this value or getter definition, or NoSymbol if none exists */
final def setter(base: Symbol): Symbol =
base.info.decl(nme.getterToSetter(nme.getterName(name))) filter (_.hasFlag(ACCESSOR))
/** The case factory corresponding to this case class
* @pre case class is a member of some other class or package
*/
final def caseFactory: Symbol = {
var facname = name.toTermName
if (privateWithin.isClass && !privateWithin.isModuleClass && !hasFlag(EXPANDEDNAME))
facname = privateWithin.expandedName(facname)
initialize.owner.info.decl(facname).suchThat(_.isCaseFactory)
}
/** 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
* term symbol rename it by expanding its name to avoid name clashes
*/
final def makeNotPrivate(base: Symbol) {
if (this hasFlag PRIVATE) {
setFlag(notPRIVATE)
if (!hasFlag(DEFERRED) && isTerm) setFlag(lateFINAL)
if (!isStaticModule && !isClassConstructor) {
expandName(base)
if (isModule) moduleClass.makeNotPrivate(base)
}
}
}
/** change name by appending $$<fully-qualified-name-of-class `base'>
* Do the same for any accessed symbols or setters/getters
*/
def expandName(base: Symbol) {
if (this.isTerm && this != NoSymbol && !hasFlag(EXPANDEDNAME)) {
setFlag(EXPANDEDNAME)
if (hasFlag(ACCESSOR) && !hasFlag(DEFERRED)) {
accessed.expandName(base)
} else if (hasGetter) {
getter(owner).expandName(base)
setter(owner).expandName(base)
}
name = base.expandedName(name)
if (isType) name = name.toTypeName
}
}
/** The expanded name of `name' relative to this class as base
*/
def expandedName(name: Name): Name = {
newTermName(fullNameString('$') + nme.EXPAND_SEPARATOR_STRING + name)
}
def sourceFile: AbstractFile =
(if (isModule) moduleClass else toplevelClass).sourceFile
def sourceFile_=(f: AbstractFile): Unit =
throw new Error("sourceFile_= inapplicable for " + this)
def isFromClassFile: Boolean =
(if (isModule) moduleClass else toplevelClass).isFromClassFile
/** If this is a sealed class, its known direct subclasses. Otherwise Set.empty */
def children: Set[Symbol] = emptySymbolSet
/** Declare given subclass `sym' of this sealed class */
def addChild(sym: Symbol) {
throw new Error("addChild inapplicable for " + this)
}
// ToString -------------------------------------------------------------------
/** A tag which (in the ideal case) uniquely identifies class symbols */
final def tag: Int = fullNameString.hashCode()
/** The simple name of this Symbol */
final def simpleName: Name = name
/** String representation of symbol's definition key word */
final def keyString: String =
if (isTrait && hasFlag(JAVA)) "interface"
else if (isTrait) "trait"
else if (isClass) "class"
else if (isType && !hasFlag(PARAM)) "type"
else if (isVariable) "var"
else if (isPackage) "package"
else if (isModule) "object"
else if (isMethod) "def"
else if (isTerm && (!hasFlag(PARAM) || hasFlag(PARAMACCESSOR))) "val"
else ""
/** String representation of symbol's kind */
final def kindString: String =
if (isPackageClass)
if (settings.debug.value) "package class" else "package"
else if (isModuleClass)
if (settings.debug.value) "singleton class" else "object"
else if (isAnonymousClass) "template"
else if (isRefinementClass) ""
else if (isTrait) "trait"
else if (isClass) "class"
else if (isType) "type"
else if (isTerm && hasFlag(LAZY)) "lazy value"
else if (isVariable) "variable"
else if (isPackage) "package"
else if (isModule) "object"
else if (isClassConstructor) "constructor"
else if (isSourceMethod) "method"
else if (isTerm) "value"
else ""
/** String representation of symbol's simple name.
* If !settings.debug translates expansions of operators back to operator symbol.
* E.g. $eq => =.
* If settings.uniquId adds id.
*/
def nameString: String = {
var s = simpleName.decode.toString
if (s endsWith nme.LOCAL_SUFFIX)
s = s.substring(0, s.length - nme.LOCAL_SUFFIX.length)
s + idString
}
/** String representation of symbol's full name with <code>separator</code>
* between class names.
* Never translates expansions of operators back to operator symbol.
* Never adds id.
*/
final def fullNameString(separator: Char): String = {
assert(owner != NoSymbol, this)
var str =
if (owner.isRoot ||
owner.isEmptyPackageClass ||
owner.isInterpreterWrapper) simpleName.toString
else owner.enclClass.fullNameString(separator) + separator + simpleName
if (str.charAt(str.length - 1) == ' ') str = str.substring(0, str.length - 1)
str
}
final def fullNameString: String = fullNameString('.')
/** If settings.uniqid is set, the symbol's id, else "" */
final def idString: String =
if (settings.uniqid.value) "#"+id else ""
/** String representation, including symbol's kind
* e.g., "class Foo", "method Bar".
*/
override def toString(): String =
if (isValueParameter && owner.isSetter)
"parameter of setter "+owner.nameString
else
compose(List(kindString,
if (isClassConstructor) owner.simpleName.decode+idString else nameString))
/** String representation of location. */
final def locationString: String =
if (owner.isClass &&
((!owner.isAnonymousClass &&
!owner.isRefinementClass &&
!owner.isInterpreterWrapper &&
!owner.isRoot &&
!owner.isEmptyPackageClass) || settings.debug.value))
" in " + owner else ""
/** String representation of symbol's definition following its name */
final def infoString(tp: Type): String = {
def typeParamsString: String = tp match {
case PolyType(tparams, _) if (tparams.length != 0) =>
(tparams map (_.defString)).mkString("[", ",", "]")
case _ =>
""
}
if (isClass)
typeParamsString + " extends " + tp.resultType
else if (isAliasType)
typeParamsString + " = " + tp.resultType
else if (isAbstractType)
typeParamsString + {
tp.resultType match {
case TypeBounds(lo, hi) =>
(if (lo.typeSymbol == AllClass) "" else " >: " + lo) +
(if (hi.typeSymbol == AnyClass) "" else " <: " + hi)
case rtp =>
"<: " + rtp
}
}
else if (isModule)
moduleClass.infoString(tp)
else
tp match {
case PolyType(tparams, res) =>
typeParamsString + infoString(res)
case MethodType(pts, res) =>
pts.mkString("(", ",", ")") + infoString(res)
case _ =>
": " + tp
}
}
def infosString = infos.toString()
/** String representation of symbol's variance */
def varianceString: String =
if (variance == 1) "+"
else if (variance == -1) "-"
else ""
/** String representation of symbol's definition */
def defString: String = {
val f = if (settings.debug.value) flags
else if (owner.isRefinementClass) flags & ExplicitFlags & ~OVERRIDE
else flags & ExplicitFlags
compose(List(flagsToString(f), keyString, varianceString + nameString + infoString(rawInfo)))
}
/** Concatenate strings separated by spaces */
private def compose(ss: List[String]): String =
ss.filter("" !=).mkString("", " ", "")
}
/** A class for term symbols */
class TermSymbol(initOwner: Symbol, initPos: Position, initName: Name)
extends Symbol(initOwner, initPos, initName) {
override def isTerm = true
privateWithin = NoSymbol
protected var referenced: Symbol = NoSymbol
def cloneSymbolImpl(owner: Symbol): Symbol = {
val clone = new TermSymbol(owner, pos, name)
clone.referenced = referenced
clone
}
override def alias: Symbol =
if (hasFlag(SUPERACCESSOR | PARAMACCESSOR | MIXEDIN)) initialize.referenced
else NoSymbol
def setAlias(alias: Symbol): TermSymbol = {
assert(alias != NoSymbol, this)
assert(!(alias hasFlag OVERLOADED), alias)
assert(hasFlag(SUPERACCESSOR | PARAMACCESSOR | MIXEDIN), this)
referenced = alias
this
}
override def outerSource: Symbol =
if (name endsWith nme.OUTER) initialize.referenced
else NoSymbol
override def moduleClass: Symbol =
if (hasFlag(MODULE)) referenced else NoSymbol
def setModuleClass(clazz: Symbol): TermSymbol = {
assert(hasFlag(MODULE))
referenced = clazz
this
}
def setLazyAccessor(sym: Symbol): TermSymbol = {
assert(hasFlag(LAZY) && referenced == NoSymbol, this)
referenced = sym
this
}
override def lazyAccessor: Symbol = {
assert(hasFlag(LAZY), this)
referenced
}
}
/** A class for module symbols */
class ModuleSymbol(initOwner: Symbol, initPos: Position, initName: Name)
extends TermSymbol(initOwner, initPos, initName) {
private var flatname = nme.EMPTY
override def owner: Symbol =
if (phase.flatClasses && !hasFlag(METHOD) &&
rawowner != NoSymbol && !rawowner.isPackageClass) rawowner.owner
else rawowner
override def name: Name =
if (phase.flatClasses && !hasFlag(METHOD) &&
rawowner != NoSymbol && !rawowner.isPackageClass) {
if (flatname == nme.EMPTY) {
assert(rawowner.isClass)
flatname = newTermName(rawowner.name.toString() + "$" + rawname)
}
flatname
} else rawname
override def cloneSymbolImpl(owner: Symbol): Symbol = {
val clone = new ModuleSymbol(owner, pos, name)
clone.referenced = referenced
clone
}
}
/** A class of type symbols. Alias and abstract types are direct instances
* of this class. Classes are instances of a subclass.
*/
class TypeSymbol(initOwner: Symbol, initPos: Position, initName: Name)
extends Symbol(initOwner, initPos, initName) {
privateWithin = NoSymbol
private var tyconCache: Type = null
private var tyconRunId = NoRunId
private var tpeCache: Type = _
private var tpePeriod = NoPeriod
override def isType = true
override def isTypeMember = true
override def isAbstractType = hasFlag(DEFERRED)
override def isAliasType = !hasFlag(DEFERRED)
override def tpe: Type = {
if (tpeCache eq NoType) throw CyclicReference(this, typeConstructor)
if (tpePeriod != currentPeriod) {
if (isValid(tpePeriod)) {
tpePeriod = currentPeriod
} else {
if (isInitialized) tpePeriod = currentPeriod
tpeCache = NoType
val targs = if (phase.erasedTypes && this != ArrayClass) List()
else unsafeTypeParams map (_.typeConstructor) //@M! use typeConstructor to generate dummy type arguments,
// sym.tpe should not be called on a symbol that's supposed to be a higher-kinded type
// memberType should be used instead, that's why it uses tpeHK and not tpe
tpeCache = typeRef(if (hasFlag(PARAM | EXISTENTIAL)) NoPrefix else owner.thisType,
this, targs)
}
}
assert(tpeCache ne null/*, "" + this + " " + phase*/)//debug
tpeCache
}
override def typeConstructor: Type = {
if ((tyconCache eq null) || tyconRunId != currentRunId) {
tyconCache = typeRef(if (hasFlag(PARAM | EXISTENTIAL)) NoPrefix else owner.thisType,
this, List())
tyconRunId = currentRunId
}
assert(tyconCache ne null)
tyconCache
}
override def setInfo(tp: Type): this.type = {
tpePeriod = NoPeriod
tyconCache = null
if (tp.isComplete)
if (tp.isInstanceOf[PolyType]) resetFlag(MONOMORPHIC)
else if (!tp.isInstanceOf[AnnotatedType]) setFlag(MONOMORPHIC)
super.setInfo(tp)
this
}
override def reset(completer: Type) {
super.reset(completer)
tpePeriod = NoPeriod
tyconRunId = NoRunId
}
def cloneSymbolImpl(owner: Symbol): Symbol =
new TypeSymbol(owner, pos, name)
if (util.Statistics.enabled) typeSymbolCount = typeSymbolCount + 1
}
/** A class for type parameters viewed from inside their scopes */
class TypeSkolem(initOwner: Symbol, initPos: Position,
initName: Name, origin: AnyRef)
extends TypeSymbol(initOwner, initPos, initName) {
override def isSkolem = true
override def deSkolemize = origin match {
case s: Symbol => s
case _ => this
}
override def unpackLocation = origin
override def typeParams = info.typeParams //@M! (not deSkolemize.typeParams!!), also can't leave superclass definition: use info, not rawInfo
override def cloneSymbolImpl(owner: Symbol): Symbol = {
throw new Error("should not clone a type skolem")
}
override def nameString: String =
if (settings.debug.value) (super.nameString + "&")
else super.nameString
}
/** A class for class symbols */
class ClassSymbol(initOwner: Symbol, initPos: Position, initName: Name)
extends TypeSymbol(initOwner, initPos, initName) {
/** The classfile from which this class was loaded. Maybe null. */
var classFile: AbstractFile = null;
private var source: AbstractFile = null
override def sourceFile =
if (owner.isPackageClass) source else super.sourceFile
override def sourceFile_=(f: AbstractFile) {
//System.err.println("set source file of " + this + ": " + f);
source = f
}
override def isFromClassFile = {
if (classFile ne null) true
else if (owner.isPackageClass) false
else super.isFromClassFile
}
private var thissym: Symbol = this
override def isClass: Boolean = true
override def isTypeMember = false
override def isAbstractType = false
override def isAliasType = false
override def reset(completer: Type) {
super.reset(completer)
thissym = this
}
private var flatname = nme.EMPTY
override def owner: Symbol =
if (phase.flatClasses && rawowner != NoSymbol && !rawowner.isPackageClass) rawowner.owner
else rawowner
override def name: Name =
if (phase.flatClasses && rawowner != NoSymbol && !rawowner.isPackageClass) {
if (flatname == nme.EMPTY) {
assert(rawowner.isClass)
flatname = newTypeName(rawowner.name.toString() + "$" + rawname)
}
flatname
} else rawname
private var thisTypeCache: Type = _
private var thisTypePeriod = NoPeriod
/** the type this.type in this class */
override def thisType: Type = {
val period = thisTypePeriod
if (period != currentPeriod) {
thisTypePeriod = currentPeriod
if (!isValid(period)) thisTypeCache = mkThisType(this)
}
thisTypeCache
}
/** A symbol carrying the self type of the class as its type */
override def thisSym: Symbol = thissym
override def typeOfThis: Type =
if (getFlag(MODULE | IMPLCLASS) == MODULE && owner != NoSymbol)
singleType(owner.thisType, sourceModule)
else thissym.tpe
/** Sets the self type of the class */
override def typeOfThis_=(tp: Type) {
thissym = newThisSym(pos).setInfo(tp)
}
override def cloneSymbolImpl(owner: Symbol): Symbol = {
assert(!isModuleClass)
val clone = new ClassSymbol(owner, pos, name)
if (thisSym != this) {
clone.typeOfThis = typeOfThis
clone.thisSym.name = thisSym.name
}
clone
}
override def sourceModule =
if (isModuleClass) linkedModuleOfClass else NoSymbol
private var childSet: Set[Symbol] = emptySymbolSet
override def children: Set[Symbol] = childSet
override def addChild(sym: Symbol) { childSet = childSet + sym }
if (util.Statistics.enabled) classSymbolCount = classSymbolCount + 1
}
/** A class for module class symbols
* Note: Not all module classes are of this type; when unpickled, we get
* plain class symbols!
*/
class ModuleClassSymbol(owner: Symbol, pos: Position, name: Name)
extends ClassSymbol(owner, pos, name) {
private var module: Symbol = null
def this(module: TermSymbol) = {
this(module.owner, module.pos, module.name.toTypeName)
setFlag(module.getFlag(ModuleToClassFlags) | MODULE | FINAL)
setSourceModule(module)
}
override def sourceModule = module
def setSourceModule(module: Symbol) { this.module = module }
}
/** An object repreesenting a missing symbol */
object NoSymbol extends Symbol(null, NoPosition, nme.NOSYMBOL) {
setInfo(NoType)
privateWithin = this
override def setInfo(info: Type): this.type = {
infos = TypeHistory(1, NoType, null)
rawflags = rawflags & ~ LOCKED
validTo = currentPeriod
this
}
override def defString: String = toString
override def enclClass: Symbol = this
override def toplevelClass: Symbol = this
override def enclMethod: Symbol = this
override def owner: Symbol = throw new Error("no-symbol does not have owner")
override def sourceFile: AbstractFile = null
override def ownerChain: List[Symbol] = List()
override def alternatives: List[Symbol] = List()
override def reset(completer: Type) {}
override def info: Type = NoType
override def rawInfo: Type = NoType
override def accessBoundary(base: Symbol): Symbol = RootClass
def cloneSymbolImpl(owner: Symbol): Symbol = throw new Error()
}
def cloneSymbols(syms: List[Symbol]): List[Symbol] = {
val syms1 = syms map (_.cloneSymbol)
for (sym1 <- syms1) sym1.setInfo(sym1.info.substSym(syms, syms1))
syms1
}
def cloneSymbols(syms: List[Symbol], owner: Symbol): List[Symbol] = {
val syms1 = syms map (_.cloneSymbol(owner))
for (sym1 <- syms1) sym1.setInfo(sym1.info.substSym(syms, syms1))
syms1
}
/** An exception for cyclic references of symbol definitions */
case class CyclicReference(sym: Symbol, info: Type)
extends TypeError("illegal cyclic reference involving " + sym)
/** A class for type histories */
private sealed case class TypeHistory(var validFrom: Period, info: Type, prev: TypeHistory) {
assert((prev eq null) || phaseId(validFrom) > phaseId(prev.validFrom), this)
assert(validFrom != NoPeriod)
override def toString() =
"TypeHistory(" + phaseOf(validFrom)+":"+runId(validFrom) + "," + info + "," + prev + ")"
}
}
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