package dotty.tools
package dotc
package ast
import core._
import Types._, Names._, NameOps._, Flags._, util.Positions._, Contexts._, Constants._
import SymDenotations._, Symbols._, Denotations._, StdNames._, Comments._
import annotation.tailrec
import language.higherKinds
import collection.IndexedSeqOptimized
import collection.immutable.IndexedSeq
import collection.mutable.ListBuffer
import parsing.Tokens.Token
import printing.Printer
import util.{Stats, Attachment, Property, DotClass}
import annotation.unchecked.uncheckedVariance
import language.implicitConversions
object Trees {
// Note: it would be more logical to make Untyped = Nothing.
// However, this interacts in a bad way with Scala's current type inference.
// In fact, we cannot write something like Select(pre, name), where pre is
// of type Tree[Nothing]; type inference will treat the Nothing as an uninstantiated
// value and will not infer Nothing as the type parameter for Select.
// We should come back to this issue once type inference is changed.
type Untyped = Null
/** The total number of created tree nodes, maintained if Stats.enabled */
@sharable var ntrees = 0
/** Property key for trees with documentation strings attached */
val DocComment = new Property.Key[Comment]
@sharable private var nextId = 0 // for debugging
type LazyTree = AnyRef /* really: Tree | Lazy[Tree] */
type LazyTreeList = AnyRef /* really: List[Tree] | Lazy[List[Tree]] */
/** Trees take a parameter indicating what the type of their `tpe` field
* is. Two choices: `Type` or `Untyped`.
* Untyped trees have type `Tree[Untyped]`.
*
* Tree typing uses a copy-on-write implementation:
*
* - You can never observe a `tpe` which is `null` (throws an exception)
* - So when creating a typed tree with `withType` we can re-use
* the existing tree transparently, assigning its `tpe` field,
* provided it was `null` before.
* - It is impossible to embed untyped trees in typed ones.
* - Typed trees can be embedded in untyped ones provided they are rooted
* in a TypedSplice node.
* - Type checking an untyped tree should remove all embedded `TypedSplice`
* nodes.
*/
abstract class Tree[-T >: Untyped] extends Positioned
with Product
with Attachment.Container
with printing.Showable
with Cloneable {
if (Stats.enabled) ntrees += 1
private def nxId = {
nextId += 1
//assert(nextId != 199, this)
nextId
}
/** A unique identifier for this tree. Used for debugging, and potentially
* tracking presentation compiler interactions
*/
private var myUniqueId: Int = nxId
def uniqueId = myUniqueId
/** The type constructor at the root of the tree */
type ThisTree[T >: Untyped] <: Tree[T]
private[this] var myTpe: T = _
/** Destructively set the type of the tree. This should be called only when it is known that
* it is safe under sharing to do so. One use-case is in the withType method below
* which implements copy-on-write. Another use-case is in method interpolateAndAdapt in Typer,
* where we overwrite with a simplified version of the type itself.
*/
private[dotc] def overwriteType(tpe: T) = {
if (this.isInstanceOf[Template[_]]) assert(tpe.isInstanceOf[WithFixedSym], s"$this <--- $tpe")
myTpe = tpe
}
/** The type of the tree. In case of an untyped tree,
* an UnAssignedTypeException is thrown. (Overridden by empty trees)
*/
def tpe: T @uncheckedVariance = {
if (myTpe == null)
throw new UnAssignedTypeException(this)
myTpe
}
/** Copy `tpe` attribute from tree `from` into this tree, independently
* whether it is null or not.
final def copyAttr[U >: Untyped](from: Tree[U]): ThisTree[T] = {
val t1 = this.withPos(from.pos)
val t2 =
if (from.myTpe != null) t1.withType(from.myTpe.asInstanceOf[Type])
else t1
t2.asInstanceOf[ThisTree[T]]
}
*/
/** Return a typed tree that's isomorphic to this tree, but has given
* type. (Overridden by empty trees)
*/
def withType(tpe: Type)(implicit ctx: Context): ThisTree[Type] = {
if (tpe.isInstanceOf[ErrorType]) assert(ctx.reporter.errorsReported)
withTypeUnchecked(tpe)
}
def withTypeUnchecked(tpe: Type): ThisTree[Type] = {
val tree =
(if (myTpe == null ||
(myTpe.asInstanceOf[AnyRef] eq tpe.asInstanceOf[AnyRef])) this
else clone).asInstanceOf[Tree[Type]]
tree overwriteType tpe
tree.asInstanceOf[ThisTree[Type]]
}
/** Does the tree have its type field set? Note: this operation is not
* referentially transparent, because it can observe the withType
* modifications. Should be used only in special circumstances (we
* need it for printing trees with optional type info).
*/
final def hasType: Boolean = myTpe != null
final def typeOpt: Type = myTpe match {
case tp: Type => tp
case _ => NoType
}
/** The denotation referred tno by this tree.
* Defined for `DenotingTree`s and `ProxyTree`s, NoDenotation for other
* kinds of trees
*/
def denot(implicit ctx: Context): Denotation = NoDenotation
/** Shorthand for `denot.symbol`. */
final def symbol(implicit ctx: Context): Symbol = denot.symbol
/** Does this tree represent a type? */
def isType: Boolean = false
/** Does this tree represent a term? */
def isTerm: Boolean = false
/** Is this a legal part of a pattern which is not at the same time a term? */
def isPattern: Boolean = false
/** Does this tree define a new symbol that is not defined elsewhere? */
def isDef: Boolean = false
/** Is this tree either the empty tree or the empty ValDef or an empty type ident? */
def isEmpty: Boolean = false
/** Convert tree to a list. Gives a singleton list, except
* for thickets which return their element trees.
*/
def toList: List[Tree[T]] = this :: Nil
/** if this tree is the empty tree, the alternative, else this tree */
def orElse[U >: Untyped <: T](that: => Tree[U]): Tree[U] =
if (this eq genericEmptyTree) that else this
/** The number of nodes in this tree */
def treeSize: Int = {
var s = 1
def addSize(elem: Any): Unit = elem match {
case t: Tree[_] => s += t.treeSize
case ts: List[_] => ts foreach addSize
case _ =>
}
productIterator foreach addSize
s
}
/** If this is a thicket, perform `op` on each of its trees
* otherwise, perform `op` ion tree itself.
*/
def foreachInThicket(op: Tree[T] => Unit): Unit = op(this)
override def toText(printer: Printer) = printer.toText(this)
override def hashCode(): Int = uniqueId // for debugging; was: System.identityHashCode(this)
override def equals(that: Any) = this eq that.asInstanceOf[AnyRef]
override def clone: Tree[T] = {
val tree = super.clone.asInstanceOf[Tree[T]]
tree.myUniqueId = nxId
tree
}
}
class UnAssignedTypeException[T >: Untyped](tree: Tree[T]) extends RuntimeException {
override def getMessage: String = s"type of $tree is not assigned"
}
// ------ Categories of trees -----------------------------------
/** Instances of this class are trees for which isType is definitely true.
* Note that some trees have isType = true without being TypTrees (e.g. Ident, AnnotatedTree)
*/
trait TypTree[-T >: Untyped] extends Tree[T] {
type ThisTree[-T >: Untyped] <: TypTree[T]
override def isType = true
}
/** Instances of this class are trees for which isTerm is definitely true.
* Note that some trees have isTerm = true without being TermTrees (e.g. Ident, AnnotatedTree)
*/
trait TermTree[-T >: Untyped] extends Tree[T] {
type ThisTree[-T >: Untyped] <: TermTree[T]
override def isTerm = true
}
/** Instances of this class are trees which are not terms but are legal
* parts of patterns.
*/
trait PatternTree[-T >: Untyped] extends Tree[T] {
type ThisTree[-T >: Untyped] <: PatternTree[T]
override def isPattern = true
}
/** Tree's denotation can be derived from its type */
abstract class DenotingTree[-T >: Untyped] extends Tree[T] {
type ThisTree[-T >: Untyped] <: DenotingTree[T]
override def denot(implicit ctx: Context) = tpe match {
case tpe: NamedType => tpe.denot
case tpe: ThisType => tpe.cls.denot
case tpe: AnnotatedType => tpe.stripAnnots match {
case tpe: NamedType => tpe.denot
case tpe: ThisType => tpe.cls.denot
case _ => NoDenotation
}
case _ => NoDenotation
}
}
/** Tree's denot/isType/isTerm properties come from a subtree
* identified by `forwardTo`.
*/
abstract class ProxyTree[-T >: Untyped] extends Tree[T] {
type ThisTree[-T >: Untyped] <: ProxyTree[T]
def forwardTo: Tree[T]
override def denot(implicit ctx: Context): Denotation = forwardTo.denot
override def isTerm = forwardTo.isTerm
override def isType = forwardTo.isType
}
/** Tree has a name */
abstract class NameTree[-T >: Untyped] extends DenotingTree[T] {
type ThisTree[-T >: Untyped] <: NameTree[T]
def name: Name
}
/** Tree refers by name to a denotation */
abstract class RefTree[-T >: Untyped] extends NameTree[T] {
type ThisTree[-T >: Untyped] <: RefTree[T]
def qualifier: Tree[T]
override def isType = name.isTypeName
override def isTerm = name.isTermName
}
/** Tree defines a new symbol */
trait DefTree[-T >: Untyped] extends DenotingTree[T] {
type ThisTree[-T >: Untyped] <: DefTree[T]
override def isDef = true
def namedType = tpe.asInstanceOf[NamedType]
}
/** Tree defines a new symbol and carries modifiers.
* The position of a MemberDef contains only the defined identifier or pattern.
* The envelope of a MemberDef contains the whole definition and has its point
* on the opening keyword (or the next token after that if keyword is missing).
*/
abstract class MemberDef[-T >: Untyped] extends NameTree[T] with DefTree[T] {
type ThisTree[-T >: Untyped] <: MemberDef[T]
private[this] var myMods: untpd.Modifiers = null
private[dotc] def rawMods: untpd.Modifiers =
if (myMods == null) untpd.EmptyModifiers else myMods
def rawComment: Option[Comment] = getAttachment(DocComment)
def withMods(mods: untpd.Modifiers): ThisTree[Untyped] = {
val tree = if (myMods == null || (myMods == mods)) this else clone.asInstanceOf[MemberDef[Untyped]]
tree.setMods(mods)
tree.asInstanceOf[ThisTree[Untyped]]
}
def withFlags(flags: FlagSet): ThisTree[Untyped] = withMods(untpd.Modifiers(flags))
def setComment(comment: Option[Comment]): ThisTree[Untyped] = {
comment.map(putAttachment(DocComment, _))
asInstanceOf[ThisTree[Untyped]]
}
protected def setMods(mods: untpd.Modifiers) = myMods = mods
/** The position of the name defined by this definition.
* This is a point position if the definition is synthetic, or a range position
* if the definition comes from source.
* It might also be that the definition does not have a position (for instance when synthesized by
* a calling chain from `viewExists`), in that case the return position is NoPosition.
*/
def namePos =
if (pos.exists)
if (rawMods.is(Synthetic)) Position(pos.point, pos.point)
else Position(pos.point, pos.point + name.stripModuleClassSuffix.lastPart.length, pos.point)
else pos
}
/** A ValDef or DefDef tree */
trait ValOrDefDef[-T >: Untyped] extends MemberDef[T] with WithLazyField[Tree[T]] {
def tpt: Tree[T]
def unforcedRhs: LazyTree = unforced
def rhs(implicit ctx: Context): Tree[T] = forceIfLazy
}
// ----------- Tree case classes ------------------------------------
/** name */
case class Ident[-T >: Untyped] private[ast] (name: Name)
extends RefTree[T] {
type ThisTree[-T >: Untyped] = Ident[T]
def qualifier: Tree[T] = genericEmptyTree
/** Is this a `BackquotedIdent` ? */
def isBackquoted: Boolean = false
}
class BackquotedIdent[-T >: Untyped] private[ast] (name: Name)
extends Ident[T](name) {
override def isBackquoted: Boolean = true
override def toString = s"BackquotedIdent($name)"
}
/** qualifier.name, or qualifier#name, if qualifier is a type */
case class Select[-T >: Untyped] private[ast] (qualifier: Tree[T], name: Name)
extends RefTree[T] {
type ThisTree[-T >: Untyped] = Select[T]
}
class SelectWithSig[-T >: Untyped] private[ast] (qualifier: Tree[T], name: Name, val sig: Signature)
extends Select[T](qualifier, name) {
override def toString = s"SelectWithSig($qualifier, $name, $sig)"
}
/** qual.this */
case class This[-T >: Untyped] private[ast] (qual: untpd.Ident)
extends DenotingTree[T] with TermTree[T] {
type ThisTree[-T >: Untyped] = This[T]
// Denotation of a This tree is always the underlying class; needs correction for modules.
override def denot(implicit ctx: Context): Denotation = {
tpe match {
case tpe @ TermRef(pre, _) if tpe.symbol is Module =>
tpe.symbol.moduleClass.denot.asSeenFrom(pre)
case _ =>
super.denot
}
}
}
/** C.super[mix], where qual = C.this */
case class Super[-T >: Untyped] private[ast] (qual: Tree[T], mix: untpd.Ident)
extends ProxyTree[T] with TermTree[T] {
type ThisTree[-T >: Untyped] = Super[T]
def forwardTo = qual
}
abstract class GenericApply[-T >: Untyped] extends ProxyTree[T] with TermTree[T] {
type ThisTree[-T >: Untyped] <: GenericApply[T]
val fun: Tree[T]
val args: List[Tree[T]]
def forwardTo = fun
}
/** fun(args) */
case class Apply[-T >: Untyped] private[ast] (fun: Tree[T], args: List[Tree[T]])
extends GenericApply[T] {
type ThisTree[-T >: Untyped] = Apply[T]
}
/** fun[args] */
case class TypeApply[-T >: Untyped] private[ast] (fun: Tree[T], args: List[Tree[T]])
extends GenericApply[T] {
type ThisTree[-T >: Untyped] = TypeApply[T]
}
/** const */
case class Literal[-T >: Untyped] private[ast] (const: Constant)
extends TermTree[T] {
type ThisTree[-T >: Untyped] = Literal[T]
}
/** new tpt, but no constructor call */
case class New[-T >: Untyped] private[ast] (tpt: Tree[T])
extends TermTree[T] {
type ThisTree[-T >: Untyped] = New[T]
}
/** expr : tpt */
case class Typed[-T >: Untyped] private[ast] (expr: Tree[T], tpt: Tree[T])
extends ProxyTree[T] with TermTree[T] {
type ThisTree[-T >: Untyped] = Typed[T]
def forwardTo = expr
}
/** name = arg, in a parameter list */
case class NamedArg[-T >: Untyped] private[ast] (name: Name, arg: Tree[T])
extends Tree[T] {
type ThisTree[-T >: Untyped] = NamedArg[T]
}
/** name = arg, outside a parameter list */
case class Assign[-T >: Untyped] private[ast] (lhs: Tree[T], rhs: Tree[T])
extends TermTree[T] {
type ThisTree[-T >: Untyped] = Assign[T]
}
/** { stats; expr } */
case class Block[-T >: Untyped] private[ast] (stats: List[Tree[T]], expr: Tree[T])
extends TermTree[T] {
type ThisTree[-T >: Untyped] = Block[T]
}
/** if cond then thenp else elsep */
case class If[-T >: Untyped] private[ast] (cond: Tree[T], thenp: Tree[T], elsep: Tree[T])
extends TermTree[T] {
type ThisTree[-T >: Untyped] = If[T]
}
/** A closure with an environment and a reference to a method.
* @param env The captured parameters of the closure
* @param meth A ref tree that refers to the method of the closure.
* The first (env.length) parameters of that method are filled
* with env values.
* @param tpt Either EmptyTree or a TypeTree. If tpt is EmptyTree the type
* of the closure is a function type, otherwise it is the type
* given in `tpt`, which must be a SAM type.
*/
case class Closure[-T >: Untyped] private[ast] (env: List[Tree[T]], meth: Tree[T], tpt: Tree[T])
extends TermTree[T] {
type ThisTree[-T >: Untyped] = Closure[T]
}
/** selector match { cases } */
case class Match[-T >: Untyped] private[ast] (selector: Tree[T], cases: List[CaseDef[T]])
extends TermTree[T] {
type ThisTree[-T >: Untyped] = Match[T]
}
/** case pat if guard => body; only appears as child of a Match */
case class CaseDef[-T >: Untyped] private[ast] (pat: Tree[T], guard: Tree[T], body: Tree[T])
extends Tree[T] {
type ThisTree[-T >: Untyped] = CaseDef[T]
}
/** return expr
* where `from` refers to the method from which the return takes place
* After program transformations this is not necessarily the enclosing method, because
* closures can intervene.
*/
case class Return[-T >: Untyped] private[ast] (expr: Tree[T], from: Tree[T] = genericEmptyTree)
extends TermTree[T] {
type ThisTree[-T >: Untyped] = Return[T]
}
/** try block catch handler finally finalizer
*
* Note: if the handler is a case block CASES of the form
*
* { case1 ... caseN }
*
* the parser returns Match(EmptyTree, CASES). Desugaring and typing this yields a closure
* node
*
* { def $anonfun(x: Throwable) = x match CASES; Closure(Nil, $anonfun) }
*
* At some later stage when we normalize the try we can revert this to
*
* Match(EmptyTree, CASES)
*
* or else if stack is non-empty
*
* Match(EmptyTree, <case x: Throwable => $anonfun(x)>)
*/
case class Try[-T >: Untyped] private[ast] (expr: Tree[T], cases: List[CaseDef[T]], finalizer: Tree[T])
extends TermTree[T] {
type ThisTree[-T >: Untyped] = Try[T]
}
/** Seq(elems)
* @param tpt The element type of the sequence.
*/
case class SeqLiteral[-T >: Untyped] private[ast] (elems: List[Tree[T]], elemtpt: Tree[T])
extends Tree[T] {
type ThisTree[-T >: Untyped] = SeqLiteral[T]
}
/** Array(elems) */
class JavaSeqLiteral[T >: Untyped] private[ast] (elems: List[Tree[T]], elemtpt: Tree[T])
extends SeqLiteral(elems, elemtpt) {
override def toString = s"JavaSeqLiteral($elems, $elemtpt)"
}
/** A tree representing inlined code.
*
* @param call Info about the original call that was inlined
* Until PostTyper, this is the full call, afterwards only
* a reference to the toplevel class from which the call was inlined.
* @param bindings Bindings for proxies to be used in the inlined code
* @param expansion The inlined tree, minus bindings.
*
* The full inlined code is equivalent to
*
* { bindings; expansion }
*
* The reason to keep `bindings` separate is because they are typed in a
* different context: `bindings` represent the arguments to the inlined
* call, whereas `expansion` represents the body of the inlined function.
*/
case class Inlined[-T >: Untyped] private[ast] (call: tpd.Tree, bindings: List[MemberDef[T]], expansion: Tree[T])
extends Tree[T] {
type ThisTree[-T >: Untyped] = Inlined[T]
}
/** A type tree that represents an existing or inferred type */
case class TypeTree[-T >: Untyped] ()
extends DenotingTree[T] with TypTree[T] {
type ThisTree[-T >: Untyped] = TypeTree[T]
override def isEmpty = !hasType
override def toString =
s"TypeTree${if (hasType) s"[$typeOpt]" else ""}"
}
/** ref.type */
case class SingletonTypeTree[-T >: Untyped] private[ast] (ref: Tree[T])
extends DenotingTree[T] with TypTree[T] {
type ThisTree[-T >: Untyped] = SingletonTypeTree[T]
}
/** left & right */
case class AndTypeTree[-T >: Untyped] private[ast] (left: Tree[T], right: Tree[T])
extends TypTree[T] {
type ThisTree[-T >: Untyped] = AndTypeTree[T]
}
/** left | right */
case class OrTypeTree[-T >: Untyped] private[ast] (left: Tree[T], right: Tree[T])
extends TypTree[T] {
type ThisTree[-T >: Untyped] = OrTypeTree[T]
}
/** tpt { refinements } */
case class RefinedTypeTree[-T >: Untyped] private[ast] (tpt: Tree[T], refinements: List[Tree[T]])
extends ProxyTree[T] with TypTree[T] {
type ThisTree[-T >: Untyped] = RefinedTypeTree[T]
def forwardTo = tpt
}
/** tpt[args] */
case class AppliedTypeTree[-T >: Untyped] private[ast] (tpt: Tree[T], args: List[Tree[T]])
extends ProxyTree[T] with TypTree[T] {
type ThisTree[-T >: Untyped] = AppliedTypeTree[T]
def forwardTo = tpt
}
/** [typeparams] -> tpt */
case class LambdaTypeTree[-T >: Untyped] private[ast] (tparams: List[TypeDef[T]], body: Tree[T])
extends TypTree[T] {
type ThisTree[-T >: Untyped] = LambdaTypeTree[T]
}
/** => T */
case class ByNameTypeTree[-T >: Untyped] private[ast] (result: Tree[T])
extends TypTree[T] {
type ThisTree[-T >: Untyped] = ByNameTypeTree[T]
}
/** >: lo <: hi */
case class TypeBoundsTree[-T >: Untyped] private[ast] (lo: Tree[T], hi: Tree[T])
extends TypTree[T] {
type ThisTree[-T >: Untyped] = TypeBoundsTree[T]
}
/** name @ body */
case class Bind[-T >: Untyped] private[ast] (name: Name, body: Tree[T])
extends NameTree[T] with DefTree[T] with PatternTree[T] {
type ThisTree[-T >: Untyped] = Bind[T]
override def isType = name.isTypeName
override def isTerm = name.isTermName
}
/** tree_1 | ... | tree_n */
case class Alternative[-T >: Untyped] private[ast] (trees: List[Tree[T]])
extends PatternTree[T] {
type ThisTree[-T >: Untyped] = Alternative[T]
}
/** The typed translation of `extractor(patterns)` in a pattern. The translation has the following
* components:
*
* @param fun is `extractor.unapply` (or, for backwards compatibility, `extractor.unapplySeq`)
* possibly with type parameters
* @param implicits Any implicit parameters passed to the unapply after the selector
* @param patterns The argument patterns in the pattern match.
*
* It is typed with same type as first `fun` argument
* Given a match selector `sel` a pattern UnApply(fun, implicits, patterns) is roughly translated as follows
*
* val result = fun(sel)(implicits)
* if (result.isDefined) "match patterns against result"
*/
case class UnApply[-T >: Untyped] private[ast] (fun: Tree[T], implicits: List[Tree[T]], patterns: List[Tree[T]])
extends PatternTree[T] {
type ThisTree[-T >: Untyped] = UnApply[T]
}
/** mods val name: tpt = rhs */
case class ValDef[-T >: Untyped] private[ast] (name: TermName, tpt: Tree[T], private var preRhs: LazyTree)
extends ValOrDefDef[T] {
type ThisTree[-T >: Untyped] = ValDef[T]
assert(isEmpty || tpt != genericEmptyTree)
def unforced = preRhs
protected def force(x: AnyRef) = preRhs = x
}
/** mods def name[tparams](vparams_1)...(vparams_n): tpt = rhs */
case class DefDef[-T >: Untyped] private[ast] (name: TermName, tparams: List[TypeDef[T]],
vparamss: List[List[ValDef[T]]], tpt: Tree[T], private var preRhs: LazyTree)
extends ValOrDefDef[T] {
type ThisTree[-T >: Untyped] = DefDef[T]
assert(tpt != genericEmptyTree)
def unforced = preRhs
protected def force(x: AnyRef) = preRhs = x
}
/** mods class name template or
* mods trait name template or
* mods type name = rhs or
* mods type name >: lo <: hi, if rhs = TypeBoundsTree(lo, hi) & (lo ne hi)
*/
case class TypeDef[-T >: Untyped] private[ast] (name: TypeName, rhs: Tree[T])
extends MemberDef[T] {
type ThisTree[-T >: Untyped] = TypeDef[T]
/** Is this a definition of a class? */
def isClassDef = rhs.isInstanceOf[Template[_]]
}
/** extends parents { self => body } */
case class Template[-T >: Untyped] private[ast] (constr: DefDef[T], parents: List[Tree[T]], self: ValDef[T], private var preBody: LazyTreeList)
extends DefTree[T] with WithLazyField[List[Tree[T]]] {
type ThisTree[-T >: Untyped] = Template[T]
def unforcedBody = unforced
def unforced = preBody
protected def force(x: AnyRef) = preBody = x
def body(implicit ctx: Context): List[Tree[T]] = forceIfLazy
}
/** import expr.selectors
* where a selector is either an untyped `Ident`, `name` or
* an untyped thicket consisting of `name` and `rename`.
*/
case class Import[-T >: Untyped] private[ast] (expr: Tree[T], selectors: List[Tree[Untyped]])
extends DenotingTree[T] {
type ThisTree[-T >: Untyped] = Import[T]
}
/** package pid { stats } */
case class PackageDef[-T >: Untyped] private[ast] (pid: RefTree[T], stats: List[Tree[T]])
extends ProxyTree[T] {
type ThisTree[-T >: Untyped] = PackageDef[T]
def forwardTo = pid
}
/** arg @annot */
case class Annotated[-T >: Untyped] private[ast] (arg: Tree[T], annot: Tree[T])
extends ProxyTree[T] {
type ThisTree[-T >: Untyped] = Annotated[T]
def forwardTo = arg
}
trait WithoutTypeOrPos[-T >: Untyped] extends Tree[T] {
override def tpe: T @uncheckedVariance = NoType.asInstanceOf[T]
override def withTypeUnchecked(tpe: Type) = this.asInstanceOf[ThisTree[Type]]
override def pos = NoPosition
override def setPos(pos: Position) = {}
}
/** Temporary class that results from translation of ModuleDefs
* (and possibly other statements).
* The contained trees will be integrated when transformed with
* a `transform(List[Tree])` call.
*/
case class Thicket[-T >: Untyped](trees: List[Tree[T]])
extends Tree[T] with WithoutTypeOrPos[T] {
type ThisTree[-T >: Untyped] = Thicket[T]
override def isEmpty: Boolean = trees.isEmpty
override def toList: List[Tree[T]] = flatten(trees)
override def toString = if (isEmpty) "EmptyTree" else "Thicket(" + trees.mkString(", ") + ")"
override def withPos(pos: Position): this.type = {
val newTrees = trees.mapConserve(_.withPos(pos))
if (trees eq newTrees)
this
else
new Thicket[T](newTrees).asInstanceOf[this.type]
}
override def pos = (NoPosition /: trees) ((pos, t) => pos union t.pos)
override def foreachInThicket(op: Tree[T] => Unit): Unit =
trees foreach (_.foreachInThicket(op))
}
class EmptyValDef[T >: Untyped] extends ValDef[T](
nme.WILDCARD, genericEmptyTree[T], genericEmptyTree[T]) with WithoutTypeOrPos[T] {
override def isEmpty: Boolean = true
setMods(untpd.Modifiers(PrivateLocal))
}
@sharable val theEmptyTree: Thicket[Type] = Thicket(Nil)
@sharable val theEmptyValDef = new EmptyValDef[Type]
def genericEmptyValDef[T >: Untyped]: ValDef[T] = theEmptyValDef.asInstanceOf[ValDef[T]]
def genericEmptyTree[T >: Untyped]: Thicket[T] = theEmptyTree.asInstanceOf[Thicket[T]]
def flatten[T >: Untyped](trees: List[Tree[T]]): List[Tree[T]] = {
var buf: ListBuffer[Tree[T]] = null
var xs = trees
while (xs.nonEmpty) {
xs.head match {
case Thicket(elems) =>
if (buf == null) {
buf = new ListBuffer
var ys = trees
while (ys ne xs) {
buf += ys.head
ys = ys.tail
}
}
for (elem <- elems) {
assert(!elem.isInstanceOf[Thicket[_]])
buf += elem
}
case tree =>
if (buf != null) buf += tree
}
xs = xs.tail
}
if (buf != null) buf.toList else trees
}
// ----- Lazy trees and tree sequences
/** A tree that can have a lazy field
* The field is represented by some private `var` which is
* proxied `unforced` and `force`. Forcing the field will
* set the `var` to the underlying value.
*/
trait WithLazyField[+T <: AnyRef] {
def unforced: AnyRef
protected def force(x: AnyRef): Unit
def forceIfLazy(implicit ctx: Context): T = unforced match {
case lzy: Lazy[T] =>
val x = lzy.complete
force(x)
x
case x: T @ unchecked => x
}
}
/** A base trait for lazy tree fields.
* These can be instantiated with Lazy instances which
* can delay tree construction until the field is first demanded.
*/
trait Lazy[T <: AnyRef] {
def complete(implicit ctx: Context): T
}
// ----- Generic Tree Instances, inherited from `tpt` and `untpd`.
abstract class Instance[T >: Untyped <: Type] extends DotClass { inst =>
type Tree = Trees.Tree[T]
type TypTree = Trees.TypTree[T]
type TermTree = Trees.TermTree[T]
type PatternTree = Trees.PatternTree[T]
type DenotingTree = Trees.DenotingTree[T]
type ProxyTree = Trees.ProxyTree[T]
type NameTree = Trees.NameTree[T]
type RefTree = Trees.RefTree[T]
type DefTree = Trees.DefTree[T]
type MemberDef = Trees.MemberDef[T]
type ValOrDefDef = Trees.ValOrDefDef[T]
type Ident = Trees.Ident[T]
type BackquotedIdent = Trees.BackquotedIdent[T]
type Select = Trees.Select[T]
type SelectWithSig = Trees.SelectWithSig[T]
type This = Trees.This[T]
type Super = Trees.Super[T]
type Apply = Trees.Apply[T]
type TypeApply = Trees.TypeApply[T]
type Literal = Trees.Literal[T]
type New = Trees.New[T]
type Typed = Trees.Typed[T]
type NamedArg = Trees.NamedArg[T]
type Assign = Trees.Assign[T]
type Block = Trees.Block[T]
type If = Trees.If[T]
type Closure = Trees.Closure[T]
type Match = Trees.Match[T]
type CaseDef = Trees.CaseDef[T]
type Return = Trees.Return[T]
type Try = Trees.Try[T]
type SeqLiteral = Trees.SeqLiteral[T]
type JavaSeqLiteral = Trees.JavaSeqLiteral[T]
type Inlined = Trees.Inlined[T]
type TypeTree = Trees.TypeTree[T]
type SingletonTypeTree = Trees.SingletonTypeTree[T]
type AndTypeTree = Trees.AndTypeTree[T]
type OrTypeTree = Trees.OrTypeTree[T]
type RefinedTypeTree = Trees.RefinedTypeTree[T]
type AppliedTypeTree = Trees.AppliedTypeTree[T]
type LambdaTypeTree = Trees.LambdaTypeTree[T]
type ByNameTypeTree = Trees.ByNameTypeTree[T]
type TypeBoundsTree = Trees.TypeBoundsTree[T]
type Bind = Trees.Bind[T]
type Alternative = Trees.Alternative[T]
type UnApply = Trees.UnApply[T]
type ValDef = Trees.ValDef[T]
type DefDef = Trees.DefDef[T]
type TypeDef = Trees.TypeDef[T]
type Template = Trees.Template[T]
type Import = Trees.Import[T]
type PackageDef = Trees.PackageDef[T]
type Annotated = Trees.Annotated[T]
type Thicket = Trees.Thicket[T]
@sharable val EmptyTree: Thicket = genericEmptyTree
@sharable val EmptyValDef: ValDef = genericEmptyValDef
// ----- Auxiliary creation methods ------------------
def Thicket(trees: List[Tree]): Thicket = new Thicket(trees)
def Thicket(): Thicket = EmptyTree
def Thicket(x1: Tree, x2: Tree): Thicket = Thicket(x1 :: x2 :: Nil)
def Thicket(x1: Tree, x2: Tree, x3: Tree): Thicket = Thicket(x1 :: x2 :: x3 :: Nil)
def flatTree(xs: List[Tree]): Tree = flatten(xs) match {
case x :: Nil => x
case ys => Thicket(ys)
}
// ----- Helper classes for copying, transforming, accumulating -----------------
val cpy: TreeCopier
/** A class for copying trees. The copy methods avoid creating a new tree
* If all arguments stay the same.
*
* Note: Some of the copy methods take a context.
* These are exactly those methods that are overridden in TypedTreeCopier
* so that they selectively retype themselves. Retyping needs a context.
*/
abstract class TreeCopier {
def postProcess(tree: Tree, copied: untpd.Tree): copied.ThisTree[T]
def postProcess(tree: Tree, copied: untpd.MemberDef): copied.ThisTree[T]
def finalize(tree: Tree, copied: untpd.Tree): copied.ThisTree[T] =
postProcess(tree, copied withPos tree.pos)
def finalize(tree: Tree, copied: untpd.MemberDef): copied.ThisTree[T] =
postProcess(tree, copied withPos tree.pos)
def Ident(tree: Tree)(name: Name): Ident = tree match {
case tree: BackquotedIdent =>
if (name == tree.name) tree
else finalize(tree, new BackquotedIdent(name))
case tree: Ident if name == tree.name => tree
case _ => finalize(tree, untpd.Ident(name))
}
def Select(tree: Tree)(qualifier: Tree, name: Name)(implicit ctx: Context): Select = tree match {
case tree: SelectWithSig =>
if ((qualifier eq tree.qualifier) && (name == tree.name)) tree
else finalize(tree, new SelectWithSig(qualifier, name, tree.sig))
case tree: Select if (qualifier eq tree.qualifier) && (name == tree.name) => tree
case _ => finalize(tree, untpd.Select(qualifier, name))
}
/** Copy Ident or Select trees */
def Ref(tree: RefTree)(name: Name)(implicit ctx: Context) = tree match {
case Ident(_) => Ident(tree)(name)
case Select(qual, _) => Select(tree)(qual, name)
}
def This(tree: Tree)(qual: untpd.Ident): This = tree match {
case tree: This if qual eq tree.qual => tree
case _ => finalize(tree, untpd.This(qual))
}
def Super(tree: Tree)(qual: Tree, mix: untpd.Ident): Super = tree match {
case tree: Super if (qual eq tree.qual) && (mix eq tree.mix) => tree
case _ => finalize(tree, untpd.Super(qual, mix))
}
def Apply(tree: Tree)(fun: Tree, args: List[Tree])(implicit ctx: Context): Apply = tree match {
case tree: Apply if (fun eq tree.fun) && (args eq tree.args) => tree
case _ => finalize(tree, untpd.Apply(fun, args))
}
def TypeApply(tree: Tree)(fun: Tree, args: List[Tree])(implicit ctx: Context): TypeApply = tree match {
case tree: TypeApply if (fun eq tree.fun) && (args eq tree.args) => tree
case _ => finalize(tree, untpd.TypeApply(fun, args))
}
def Literal(tree: Tree)(const: Constant)(implicit ctx: Context): Literal = tree match {
case tree: Literal if const == tree.const => tree
case _ => finalize(tree, untpd.Literal(const))
}
def New(tree: Tree)(tpt: Tree)(implicit ctx: Context): New = tree match {
case tree: New if tpt eq tree.tpt => tree
case _ => finalize(tree, untpd.New(tpt))
}
def Typed(tree: Tree)(expr: Tree, tpt: Tree)(implicit ctx: Context): Typed = tree match {
case tree: Typed if (expr eq tree.expr) && (tpt eq tree.tpt) => tree
case _ => finalize(tree, untpd.Typed(expr, tpt))
}
def NamedArg(tree: Tree)(name: Name, arg: Tree)(implicit ctx: Context): NamedArg = tree match {
case tree: NamedArg if (name == tree.name) && (arg eq tree.arg) => tree
case _ => finalize(tree, untpd.NamedArg(name, arg))
}
def Assign(tree: Tree)(lhs: Tree, rhs: Tree)(implicit ctx: Context): Assign = tree match {
case tree: Assign if (lhs eq tree.lhs) && (rhs eq tree.rhs) => tree
case _ => finalize(tree, untpd.Assign(lhs, rhs))
}
def Block(tree: Tree)(stats: List[Tree], expr: Tree)(implicit ctx: Context): Block = tree match {
case tree: Block if (stats eq tree.stats) && (expr eq tree.expr) => tree
case _ => finalize(tree, untpd.Block(stats, expr))
}
def If(tree: Tree)(cond: Tree, thenp: Tree, elsep: Tree)(implicit ctx: Context): If = tree match {
case tree: If if (cond eq tree.cond) && (thenp eq tree.thenp) && (elsep eq tree.elsep) => tree
case _ => finalize(tree, untpd.If(cond, thenp, elsep))
}
def Closure(tree: Tree)(env: List[Tree], meth: Tree, tpt: Tree)(implicit ctx: Context): Closure = tree match {
case tree: Closure if (env eq tree.env) && (meth eq tree.meth) && (tpt eq tree.tpt) => tree
case _ => finalize(tree, untpd.Closure(env, meth, tpt))
}
def Match(tree: Tree)(selector: Tree, cases: List[CaseDef])(implicit ctx: Context): Match = tree match {
case tree: Match if (selector eq tree.selector) && (cases eq tree.cases) => tree
case _ => finalize(tree, untpd.Match(selector, cases))
}
def CaseDef(tree: Tree)(pat: Tree, guard: Tree, body: Tree)(implicit ctx: Context): CaseDef = tree match {
case tree: CaseDef if (pat eq tree.pat) && (guard eq tree.guard) && (body eq tree.body) => tree
case _ => finalize(tree, untpd.CaseDef(pat, guard, body))
}
def Return(tree: Tree)(expr: Tree, from: Tree)(implicit ctx: Context): Return = tree match {
case tree: Return if (expr eq tree.expr) && (from eq tree.from) => tree
case _ => finalize(tree, untpd.Return(expr, from))
}
def Try(tree: Tree)(expr: Tree, cases: List[CaseDef], finalizer: Tree)(implicit ctx: Context): Try = tree match {
case tree: Try if (expr eq tree.expr) && (cases eq tree.cases) && (finalizer eq tree.finalizer) => tree
case _ => finalize(tree, untpd.Try(expr, cases, finalizer))
}
def SeqLiteral(tree: Tree)(elems: List[Tree], elemtpt: Tree)(implicit ctx: Context): SeqLiteral = tree match {
case tree: JavaSeqLiteral =>
if ((elems eq tree.elems) && (elemtpt eq tree.elemtpt)) tree
else finalize(tree, new JavaSeqLiteral(elems, elemtpt))
case tree: SeqLiteral if (elems eq tree.elems) && (elemtpt eq tree.elemtpt) => tree
case _ => finalize(tree, untpd.SeqLiteral(elems, elemtpt))
}
def Inlined(tree: Tree)(call: tpd.Tree, bindings: List[MemberDef], expansion: Tree)(implicit ctx: Context): Inlined = tree match {
case tree: Inlined if (call eq tree.call) && (bindings eq tree.bindings) && (expansion eq tree.expansion) => tree
case _ => finalize(tree, untpd.Inlined(call, bindings, expansion))
}
def SingletonTypeTree(tree: Tree)(ref: Tree): SingletonTypeTree = tree match {
case tree: SingletonTypeTree if ref eq tree.ref => tree
case _ => finalize(tree, untpd.SingletonTypeTree(ref))
}
def AndTypeTree(tree: Tree)(left: Tree, right: Tree): AndTypeTree = tree match {
case tree: AndTypeTree if (left eq tree.left) && (right eq tree.right) => tree
case _ => finalize(tree, untpd.AndTypeTree(left, right))
}
def OrTypeTree(tree: Tree)(left: Tree, right: Tree): OrTypeTree = tree match {
case tree: OrTypeTree if (left eq tree.left) && (right eq tree.right) => tree
case _ => finalize(tree, untpd.OrTypeTree(left, right))
}
def RefinedTypeTree(tree: Tree)(tpt: Tree, refinements: List[Tree]): RefinedTypeTree = tree match {
case tree: RefinedTypeTree if (tpt eq tree.tpt) && (refinements eq tree.refinements) => tree
case _ => finalize(tree, untpd.RefinedTypeTree(tpt, refinements))
}
def AppliedTypeTree(tree: Tree)(tpt: Tree, args: List[Tree]): AppliedTypeTree = tree match {
case tree: AppliedTypeTree if (tpt eq tree.tpt) && (args eq tree.args) => tree
case _ => finalize(tree, untpd.AppliedTypeTree(tpt, args))
}
def LambdaTypeTree(tree: Tree)(tparams: List[TypeDef], body: Tree): LambdaTypeTree = tree match {
case tree: LambdaTypeTree if (tparams eq tree.tparams) && (body eq tree.body) => tree
case _ => finalize(tree, untpd.LambdaTypeTree(tparams, body))
}
def ByNameTypeTree(tree: Tree)(result: Tree): ByNameTypeTree = tree match {
case tree: ByNameTypeTree if result eq tree.result => tree
case _ => finalize(tree, untpd.ByNameTypeTree(result))
}
def TypeBoundsTree(tree: Tree)(lo: Tree, hi: Tree): TypeBoundsTree = tree match {
case tree: TypeBoundsTree if (lo eq tree.lo) && (hi eq tree.hi) => tree
case _ => finalize(tree, untpd.TypeBoundsTree(lo, hi))
}
def Bind(tree: Tree)(name: Name, body: Tree): Bind = tree match {
case tree: Bind if (name eq tree.name) && (body eq tree.body) => tree
case _ => finalize(tree, untpd.Bind(name, body))
}
def Alternative(tree: Tree)(trees: List[Tree]): Alternative = tree match {
case tree: Alternative if trees eq tree.trees => tree
case _ => finalize(tree, untpd.Alternative(trees))
}
def UnApply(tree: Tree)(fun: Tree, implicits: List[Tree], patterns: List[Tree]): UnApply = tree match {
case tree: UnApply if (fun eq tree.fun) && (implicits eq tree.implicits) && (patterns eq tree.patterns) => tree
case _ => finalize(tree, untpd.UnApply(fun, implicits, patterns))
}
def ValDef(tree: Tree)(name: TermName, tpt: Tree, rhs: LazyTree): ValDef = tree match {
case tree: ValDef if (name == tree.name) && (tpt eq tree.tpt) && (rhs eq tree.unforcedRhs) => tree
case _ => finalize(tree, untpd.ValDef(name, tpt, rhs))
}
def DefDef(tree: Tree)(name: TermName, tparams: List[TypeDef], vparamss: List[List[ValDef]], tpt: Tree, rhs: LazyTree): DefDef = tree match {
case tree: DefDef if (name == tree.name) && (tparams eq tree.tparams) && (vparamss eq tree.vparamss) && (tpt eq tree.tpt) && (rhs eq tree.unforcedRhs) => tree
case _ => finalize(tree, untpd.DefDef(name, tparams, vparamss, tpt, rhs))
}
def TypeDef(tree: Tree)(name: TypeName, rhs: Tree): TypeDef = tree match {
case tree: TypeDef if (name == tree.name) && (rhs eq tree.rhs) => tree
case _ => finalize(tree, untpd.TypeDef(name, rhs))
}
def Template(tree: Tree)(constr: DefDef, parents: List[Tree], self: ValDef, body: LazyTreeList): Template = tree match {
case tree: Template if (constr eq tree.constr) && (parents eq tree.parents) && (self eq tree.self) && (body eq tree.unforcedBody) => tree
case _ => finalize(tree, untpd.Template(constr, parents, self, body))
}
def Import(tree: Tree)(expr: Tree, selectors: List[untpd.Tree]): Import = tree match {
case tree: Import if (expr eq tree.expr) && (selectors eq tree.selectors) => tree
case _ => finalize(tree, untpd.Import(expr, selectors))
}
def PackageDef(tree: Tree)(pid: RefTree, stats: List[Tree]): PackageDef = tree match {
case tree: PackageDef if (pid eq tree.pid) && (stats eq tree.stats) => tree
case _ => finalize(tree, untpd.PackageDef(pid, stats))
}
def Annotated(tree: Tree)(arg: Tree, annot: Tree)(implicit ctx: Context): Annotated = tree match {
case tree: Annotated if (arg eq tree.arg) && (annot eq tree.annot) => tree
case _ => finalize(tree, untpd.Annotated(arg, annot))
}
def Thicket(tree: Tree)(trees: List[Tree]): Thicket = tree match {
case tree: Thicket if trees eq tree.trees => tree
case _ => finalize(tree, untpd.Thicket(trees))
}
// Copier methods with default arguments; these demand that the original tree
// is of the same class as the copy. We only include trees with more than 2 elements here.
def If(tree: If)(cond: Tree = tree.cond, thenp: Tree = tree.thenp, elsep: Tree = tree.elsep)(implicit ctx: Context): If =
If(tree: Tree)(cond, thenp, elsep)
def Closure(tree: Closure)(env: List[Tree] = tree.env, meth: Tree = tree.meth, tpt: Tree = tree.tpt)(implicit ctx: Context): Closure =
Closure(tree: Tree)(env, meth, tpt)
def CaseDef(tree: CaseDef)(pat: Tree = tree.pat, guard: Tree = tree.guard, body: Tree = tree.body)(implicit ctx: Context): CaseDef =
CaseDef(tree: Tree)(pat, guard, body)
def Try(tree: Try)(expr: Tree = tree.expr, cases: List[CaseDef] = tree.cases, finalizer: Tree = tree.finalizer)(implicit ctx: Context): Try =
Try(tree: Tree)(expr, cases, finalizer)
def UnApply(tree: UnApply)(fun: Tree = tree.fun, implicits: List[Tree] = tree.implicits, patterns: List[Tree] = tree.patterns): UnApply =
UnApply(tree: Tree)(fun, implicits, patterns)
def ValDef(tree: ValDef)(name: TermName = tree.name, tpt: Tree = tree.tpt, rhs: LazyTree = tree.unforcedRhs): ValDef =
ValDef(tree: Tree)(name, tpt, rhs)
def DefDef(tree: DefDef)(name: TermName = tree.name, tparams: List[TypeDef] = tree.tparams, vparamss: List[List[ValDef]] = tree.vparamss, tpt: Tree = tree.tpt, rhs: LazyTree = tree.unforcedRhs): DefDef =
DefDef(tree: Tree)(name, tparams, vparamss, tpt, rhs)
def TypeDef(tree: TypeDef)(name: TypeName = tree.name, rhs: Tree = tree.rhs): TypeDef =
TypeDef(tree: Tree)(name, rhs)
def Template(tree: Template)(constr: DefDef = tree.constr, parents: List[Tree] = tree.parents, self: ValDef = tree.self, body: LazyTreeList = tree.unforcedBody): Template =
Template(tree: Tree)(constr, parents, self, body)
}
/** Hook to indicate that a transform of some subtree should be skipped */
protected def skipTransform(tree: Tree)(implicit ctx: Context): Boolean = false
/** For untyped trees, this is just the identity.
* For typed trees, a context derived form `ctx` that records `call` as the
* innermost enclosing call for which the inlined version is currently
* processed.
*/
protected def inlineContext(call: Tree)(implicit ctx: Context): Context = ctx
abstract class TreeMap(val cpy: TreeCopier = inst.cpy) {
def transform(tree: Tree)(implicit ctx: Context): Tree =
if (skipTransform(tree)) tree
else tree match {
case Ident(name) =>
tree
case Select(qualifier, name) =>
cpy.Select(tree)(transform(qualifier), name)
case This(qual) =>
tree
case Super(qual, mix) =>
cpy.Super(tree)(transform(qual), mix)
case Apply(fun, args) =>
cpy.Apply(tree)(transform(fun), transform(args))
case TypeApply(fun, args) =>
cpy.TypeApply(tree)(transform(fun), transform(args))
case Literal(const) =>
tree
case New(tpt) =>
cpy.New(tree)(transform(tpt))
case Typed(expr, tpt) =>
cpy.Typed(tree)(transform(expr), transform(tpt))
case NamedArg(name, arg) =>
cpy.NamedArg(tree)(name, transform(arg))
case Assign(lhs, rhs) =>
cpy.Assign(tree)(transform(lhs), transform(rhs))
case Block(stats, expr) =>
cpy.Block(tree)(transformStats(stats), transform(expr))
case If(cond, thenp, elsep) =>
cpy.If(tree)(transform(cond), transform(thenp), transform(elsep))
case Closure(env, meth, tpt) =>
cpy.Closure(tree)(transform(env), transform(meth), transform(tpt))
case Match(selector, cases) =>
cpy.Match(tree)(transform(selector), transformSub(cases))
case CaseDef(pat, guard, body) =>
cpy.CaseDef(tree)(transform(pat), transform(guard), transform(body))
case Return(expr, from) =>
cpy.Return(tree)(transform(expr), transformSub(from))
case Try(block, cases, finalizer) =>
cpy.Try(tree)(transform(block), transformSub(cases), transform(finalizer))
case SeqLiteral(elems, elemtpt) =>
cpy.SeqLiteral(tree)(transform(elems), transform(elemtpt))
case Inlined(call, bindings, expansion) =>
cpy.Inlined(tree)(call, transformSub(bindings), transform(expansion)(inlineContext(call)))
case TypeTree() =>
tree
case SingletonTypeTree(ref) =>
cpy.SingletonTypeTree(tree)(transform(ref))
case AndTypeTree(left, right) =>
cpy.AndTypeTree(tree)(transform(left), transform(right))
case OrTypeTree(left, right) =>
cpy.OrTypeTree(tree)(transform(left), transform(right))
case RefinedTypeTree(tpt, refinements) =>
cpy.RefinedTypeTree(tree)(transform(tpt), transformSub(refinements))
case AppliedTypeTree(tpt, args) =>
cpy.AppliedTypeTree(tree)(transform(tpt), transform(args))
case LambdaTypeTree(tparams, body) =>
cpy.LambdaTypeTree(tree)(transformSub(tparams), transform(body))
case ByNameTypeTree(result) =>
cpy.ByNameTypeTree(tree)(transform(result))
case TypeBoundsTree(lo, hi) =>
cpy.TypeBoundsTree(tree)(transform(lo), transform(hi))
case Bind(name, body) =>
cpy.Bind(tree)(name, transform(body))
case Alternative(trees) =>
cpy.Alternative(tree)(transform(trees))
case UnApply(fun, implicits, patterns) =>
cpy.UnApply(tree)(transform(fun), transform(implicits), transform(patterns))
case EmptyValDef =>
tree
case tree @ ValDef(name, tpt, _) =>
val tpt1 = transform(tpt)
val rhs1 = transform(tree.rhs)
cpy.ValDef(tree)(name, tpt1, rhs1)
case tree @ DefDef(name, tparams, vparamss, tpt, _) =>
cpy.DefDef(tree)(name, transformSub(tparams), vparamss mapConserve (transformSub(_)), transform(tpt), transform(tree.rhs))
case tree @ TypeDef(name, rhs) =>
cpy.TypeDef(tree)(name, transform(rhs))
case tree @ Template(constr, parents, self, _) =>
cpy.Template(tree)(transformSub(constr), transform(parents), transformSub(self), transformStats(tree.body))
case Import(expr, selectors) =>
cpy.Import(tree)(transform(expr), selectors)
case PackageDef(pid, stats) =>
cpy.PackageDef(tree)(transformSub(pid), transformStats(stats))
case Annotated(arg, annot) =>
cpy.Annotated(tree)(transform(arg), transform(annot))
case Thicket(trees) =>
val trees1 = transform(trees)
if (trees1 eq trees) tree else Thicket(trees1)
}
def transformStats(trees: List[Tree])(implicit ctx: Context): List[Tree] =
transform(trees)
def transform(trees: List[Tree])(implicit ctx: Context): List[Tree] =
flatten(trees mapConserve (transform(_)))
def transformSub[Tr <: Tree](tree: Tr)(implicit ctx: Context): Tr =
transform(tree).asInstanceOf[Tr]
def transformSub[Tr <: Tree](trees: List[Tr])(implicit ctx: Context): List[Tr] =
transform(trees).asInstanceOf[List[Tr]]
}
abstract class TreeAccumulator[X] {
def apply(x: X, tree: Tree)(implicit ctx: Context): X
def apply(x: X, trees: Traversable[Tree])(implicit ctx: Context): X = (x /: trees)(apply)
def foldOver(x: X, tree: Tree)(implicit ctx: Context): X = {
def localCtx =
if (tree.hasType && tree.symbol.exists) ctx.withOwner(tree.symbol) else ctx
tree match {
case Ident(name) =>
x
case Select(qualifier, name) =>
this(x, qualifier)
case This(qual) =>
x
case Super(qual, mix) =>
this(x, qual)
case Apply(fun, args) =>
this(this(x, fun), args)
case TypeApply(fun, args) =>
this(this(x, fun), args)
case Literal(const) =>
x
case New(tpt) =>
this(x, tpt)
case Typed(expr, tpt) =>
this(this(x, expr), tpt)
case NamedArg(name, arg) =>
this(x, arg)
case Assign(lhs, rhs) =>
this(this(x, lhs), rhs)
case Block(stats, expr) =>
this(this(x, stats), expr)
case If(cond, thenp, elsep) =>
this(this(this(x, cond), thenp), elsep)
case Closure(env, meth, tpt) =>
this(this(this(x, env), meth), tpt)
case Match(selector, cases) =>
this(this(x, selector), cases)
case CaseDef(pat, guard, body) =>
this(this(this(x, pat), guard), body)
case Return(expr, from) =>
this(this(x, expr), from)
case Try(block, handler, finalizer) =>
this(this(this(x, block), handler), finalizer)
case SeqLiteral(elems, elemtpt) =>
this(this(x, elems), elemtpt)
case Inlined(call, bindings, expansion) =>
this(this(x, bindings), expansion)(inlineContext(call))
case TypeTree() =>
x
case SingletonTypeTree(ref) =>
this(x, ref)
case AndTypeTree(left, right) =>
this(this(x, left), right)
case OrTypeTree(left, right) =>
this(this(x, left), right)
case RefinedTypeTree(tpt, refinements) =>
this(this(x, tpt), refinements)
case AppliedTypeTree(tpt, args) =>
this(this(x, tpt), args)
case LambdaTypeTree(tparams, body) =>
implicit val ctx = localCtx
this(this(x, tparams), body)
case ByNameTypeTree(result) =>
this(x, result)
case TypeBoundsTree(lo, hi) =>
this(this(x, lo), hi)
case Bind(name, body) =>
this(x, body)
case Alternative(trees) =>
this(x, trees)
case UnApply(fun, implicits, patterns) =>
this(this(this(x, fun), implicits), patterns)
case tree @ ValDef(name, tpt, _) =>
implicit val ctx = localCtx
this(this(x, tpt), tree.rhs)
case tree @ DefDef(name, tparams, vparamss, tpt, _) =>
implicit val ctx = localCtx
this(this((this(x, tparams) /: vparamss)(apply), tpt), tree.rhs)
case TypeDef(name, rhs) =>
implicit val ctx = localCtx
this(x, rhs)
case tree @ Template(constr, parents, self, _) =>
this(this(this(this(x, constr), parents), self), tree.body)
case Import(expr, selectors) =>
this(x, expr)
case PackageDef(pid, stats) =>
this(this(x, pid), stats)(localCtx)
case Annotated(arg, annot) =>
this(this(x, arg), annot)
case Thicket(ts) =>
this(x, ts)
}
}
}
abstract class TreeTraverser extends TreeAccumulator[Unit] {
def traverse(tree: Tree)(implicit ctx: Context): Unit
def apply(x: Unit, tree: Tree)(implicit ctx: Context) = traverse(tree)
protected def traverseChildren(tree: Tree)(implicit ctx: Context) = foldOver((), tree)
}
/** Fold `f` over all tree nodes, in depth-first, prefix order */
class DeepFolder[X](f: (X, Tree) => X) extends TreeAccumulator[X] {
def apply(x: X, tree: Tree)(implicit ctx: Context): X = foldOver(f(x, tree), tree)
}
/** Fold `f` over all tree nodes, in depth-first, prefix order, but don't visit
* subtrees where `f` returns a different result for the root, i.e. `f(x, root) ne x`.
*/
class ShallowFolder[X](f: (X, Tree) => X) extends TreeAccumulator[X] {
def apply(x: X, tree: Tree)(implicit ctx: Context): X = {
val x1 = f(x, tree)
if (x1.asInstanceOf[AnyRef] ne x1.asInstanceOf[AnyRef]) x1
else foldOver(x1, tree)
}
}
def rename(tree: NameTree, newName: Name)(implicit ctx: Context): tree.ThisTree[T] = {
tree match {
case tree: Ident => cpy.Ident(tree)(newName)
case tree: Select => cpy.Select(tree)(tree.qualifier, newName)
case tree: Bind => cpy.Bind(tree)(newName, tree.body)
case tree: ValDef => cpy.ValDef(tree)(name = newName.asTermName)
case tree: DefDef => cpy.DefDef(tree)(name = newName.asTermName)
case tree: TypeDef => cpy.TypeDef(tree)(name = newName.asTypeName)
}
}.asInstanceOf[tree.ThisTree[T]]
}
}