/* NSC -- new Scala compiler
* Copyright 2005-2011 LAMP/EPFL
* @author Martin Odersky
*/
package scala.reflect
package api
import scala.collection.mutable.ListBuffer
// Syncnote: Trees are currently not thread-safe.
trait Trees { self: Universe =>
private[scala] var nodeCount = 0
type Modifiers <: AbsModifiers
abstract class AbsModifiers {
def hasModifier(mod: Modifier.Value): Boolean
def allModifiers: Set[Modifier.Value]
def privateWithin: Name // default: EmptyTypeName
def annotations: List[Tree] // default: List()
def mapAnnotations(f: List[Tree] => List[Tree]): Modifiers
}
def Modifiers(mods: Set[Modifier.Value] = Set(),
privateWithin: Name = EmptyTypeName,
annotations: List[Tree] = List()): Modifiers
/** Tree is the basis for scala's abstract syntax. The nodes are
* implemented as case classes, and the parameters which initialize
* a given tree are immutable: however Trees have several mutable
* fields which are manipulated in the course of typechecking,
* including pos, symbol, and tpe.
*
* Newly instantiated trees have tpe set to null (though it
* may be set immediately thereafter depending on how it is
* constructed.) When a tree is passed to the typer, typically via
* `typer.typed(tree)`, under normal circumstances the tpe must be
* null or the typer will ignore it. Furthermore, the typer is not
* required to return the same tree it was passed.
*
* Trees can be easily traversed with e.g. foreach on the root node;
* for a more nuanced traversal, subclass Traverser. Transformations
* can be considerably trickier: see the numerous subclasses of
* Transformer found around the compiler.
*
* Copying Trees should be done with care depending on whether
* it need be done lazily or strictly (see LazyTreeCopier and
* StrictTreeCopier) and on whether the contents of the mutable
* fields should be copied. The tree copiers will copy the mutable
* attributes to the new tree; calling Tree#duplicate will copy
* symbol and tpe, but all the positions will be focused.
*
* Trees can be coarsely divided into four mutually exclusive categories:
*
* - TermTrees, representing terms
* - TypTrees, representing types. Note that is `TypTree`, not `TypeTree`.
* - SymTrees, which may represent types or terms.
* - Other Trees, which have none of those as parents.
*
* SymTrees include important nodes Ident and Select, which are
* used as both terms and types; they are distinguishable based on
* whether the Name is a TermName or TypeName. The correct way for
* to test for a type or a term (on any Tree) are the isTerm/isType
* methods on Tree.
*
* "Others" are mostly syntactic or short-lived constructs. Examples
* include CaseDef, which wraps individual match cases: they are
* neither terms nor types, nor do they carry a symbol. Another
* example is Parens, which is eliminated during parsing.
*/
abstract class Tree extends Product {
val id = nodeCount
nodeCount += 1
private[this] var rawpos: Position = NoPosition
def pos = rawpos
def pos_=(pos: Position) = rawpos = pos
def setPos(pos: Position): this.type = { rawpos = pos; this }
private[this] var rawtpe: Type = _
def tpe = rawtpe
def tpe_=(t: Type) = rawtpe = t
/** Set tpe to give `tp` and return this.
*/
def setType(tp: Type): this.type = { rawtpe = tp; this }
/** Like `setType`, but if this is a previously empty TypeTree that
* fact is remembered so that resetAllAttrs will snap back.
*
* @PP: Attempting to elaborate on the above, I find: If defineType
* is called on a TypeTree whose type field is null or NoType,
* this is recorded as "wasEmpty = true". That value is used in
* ResetAttrsTraverser, which nulls out the type field of TypeTrees
* for which wasEmpty is true, leaving the others alone.
*
* resetAllAttrs is used in situations where some speculative
* typing of a tree takes place, fails, and the tree needs to be
* returned to its former state to try again. So according to me:
* using `defineType` instead of `setType` is how you communicate
* that the type being set does not depend on any previous state,
* and therefore should be abandoned if the current line of type
* inquiry doesn't work out.
*/
def defineType(tp: Type): this.type = setType(tp)
/** Note that symbol is fixed as null at this level. In SymTrees,
* it is overridden and implemented with a var, initialized to NoSymbol.
*
* Trees which are not SymTrees but which carry symbols do so by
* overriding `def symbol` to forward it elsewhere. Examples:
*
* Super(qual, _) // has qual's symbol
* Apply(fun, args) // has fun's symbol
* TypeApply(fun, args) // has fun's symbol
* AppliedTypeTree(tpt, args) // has tpt's symbol
* TypeTree(tpe) // has tpe's typeSymbol, if tpe != null
*
* Attempting to set the symbol of a Tree which does not support
* it will induce an exception.
*/
def symbol: Symbol = null
def symbol_=(sym: Symbol) { throw new UnsupportedOperationException("symbol_= inapplicable for " + this) }
def setSymbol(sym: Symbol): this.type = { symbol = sym; this }
def hasSymbol = false
def isDef = false
def isEmpty = false
def hasSymbolWhich(f: Symbol => Boolean) = hasSymbol && f(symbol)
/** The canonical way to test if a Tree represents a term.
*/
def isTerm: Boolean = this match {
case _: TermTree => true
case Bind(name, _) => name.isTermName
case Select(_, name) => name.isTermName
case Ident(name) => name.isTermName
case Annotated(_, arg) => arg.isTerm
case _ => false
}
/** The canonical way to test if a Tree represents a type.
*/
def isType: Boolean = this match {
case _: TypTree => true
case Bind(name, _) => name.isTypeName
case Select(_, name) => name.isTypeName
case Ident(name) => name.isTypeName
case Annotated(_, arg) => arg.isType
case _ => false
}
/** Apply `f` to each subtree */
def foreach(f: Tree => Unit) { new ForeachTreeTraverser(f).traverse(this) }
/** Find all subtrees matching predicate `p` */
def filter(f: Tree => Boolean): List[Tree] = {
val ft = new FilterTreeTraverser(f)
ft.traverse(this)
ft.hits.toList
}
/** Returns optionally first tree (in a preorder traversal) which satisfies predicate `p`,
* or None if none exists.
*/
def find(p: Tree => Boolean): Option[Tree] = {
val ft = new FindTreeTraverser(p)
ft.traverse(this)
ft.result
}
/** Is there part of this tree which satisfies predicate `p`? */
def exists(p: Tree => Boolean): Boolean = !find(p).isEmpty
def equalsStructure(that : Tree) = equalsStructure0(that)(_ eq _)
def equalsStructure0(that: Tree)(f: (Tree,Tree) => Boolean): Boolean =
f(this, that) || ((this.productArity == that.productArity) && {
def equals0(this0: Any, that0: Any): Boolean = (this0, that0) match {
case (x: Tree, y: Tree) => f(x, y) || (x equalsStructure0 y)(f)
case (xs: List[_], ys: List[_]) => (xs corresponds ys)(equals0)
case _ => this0 == that0
}
def compareOriginals() = (this, that) match {
case (x: TypeTree, y: TypeTree) if x.original != null && y.original != null =>
(x.original equalsStructure0 y.original)(f)
case _ =>
true
}
(this.productIterator zip that.productIterator forall { case (x, y) => equals0(x, y) }) && compareOriginals()
})
/** The direct child trees of this tree.
* EmptyTrees are always omitted. Lists are flattened.
*/
def children: List[Tree] = {
def subtrees(x: Any): List[Tree] = x match {
case EmptyTree => Nil
case t: Tree => List(t)
case xs: List[_] => xs flatMap subtrees
case _ => Nil
}
productIterator.toList flatMap subtrees
}
/** Make a copy of this tree, keeping all attributes,
* except that all positions are focused (so nothing
* in this tree will be found when searching by position).
*/
def duplicate: this.type =
duplicateTree(this).asInstanceOf[this.type]
private[scala] def copyAttrs(tree: Tree): this.type = {
pos = tree.pos
tpe = tree.tpe
if (hasSymbol) symbol = tree.symbol
this
}
override def toString: String = show(this)
override def hashCode(): Int = System.identityHashCode(this)
override def equals(that: Any) = this eq that.asInstanceOf[AnyRef]
}
/** A tree for a term. Not all terms are TermTrees; use isTerm
* to reliably identify terms.
*/
trait TermTree extends Tree
/** A tree for a type. Not all types are TypTrees; use isType
* to reliably identify types.
*/
trait TypTree extends Tree
/** A tree with a mutable symbol field, initialized to NoSymbol.
*/
trait SymTree extends Tree {
override def hasSymbol = true
override var symbol: Symbol = NoSymbol
}
/** A tree which references a symbol-carrying entity.
* References one, as opposed to defining one; definitions
* are in DefTrees.
*/
trait RefTree extends SymTree {
def name: Name
}
/** A tree which defines a symbol-carrying entity.
*/
abstract class DefTree extends SymTree {
def name: Name
override def isDef = true
}
// ----- tree node alternatives --------------------------------------
/** The empty tree */
case object EmptyTree extends TermTree {
super.tpe_=(NoType)
override def tpe_=(t: Type) =
if (t != NoType) throw new UnsupportedOperationException("tpe_=("+t+") inapplicable for <empty>")
override def isEmpty = true
}
/** Common base class for all member definitions: types, classes,
* objects, packages, vals and vars, defs.
*/
abstract class MemberDef extends DefTree {
def mods: Modifiers
def keyword: String = this match {
case TypeDef(_, _, _, _) => "type"
case ClassDef(mods, _, _, _) => if (mods hasModifier Modifier.`trait`) "trait" else "class"
case DefDef(_, _, _, _, _, _) => "def"
case ModuleDef(_, _, _) => "object"
case PackageDef(_, _) => "package"
case ValDef(mods, _, _, _) => if (mods hasModifier Modifier.mutable) "var" else "val"
case _ => ""
}
// final def hasFlag(mask: Long): Boolean = mods hasFlag mask
}
/** A packaging, such as `package pid { stats }`
*/
case class PackageDef(pid: RefTree, stats: List[Tree])
extends MemberDef {
def name = pid.name
def mods = Modifiers()
}
/** A common base class for class and object definitions.
*/
abstract class ImplDef extends MemberDef {
def impl: Template
}
/** A class definition.
*/
case class ClassDef(mods: Modifiers, name: TypeName, tparams: List[TypeDef], impl: Template)
extends ImplDef
/** An object definition, e.g. `object Foo`. Internally, objects are
* quite frequently called modules to reduce ambiguity.
*/
case class ModuleDef(mods: Modifiers, name: TermName, impl: Template)
extends ImplDef
/** A common base class for ValDefs and DefDefs.
*/
abstract class ValOrDefDef extends MemberDef {
def name: Name // can't be a TermName because macros can be type names.
def tpt: Tree
def rhs: Tree
}
/** A value definition (this includes vars as well, which differ from
* vals only in having the MUTABLE flag set in their Modifiers.)
*/
case class ValDef(mods: Modifiers, name: TermName, tpt: Tree, rhs: Tree) extends ValOrDefDef
/** A method or macro definition.
* @param name The name of the method or macro. Can be a type name in case this is a type macro
*/
case class DefDef(mods: Modifiers, name: Name, tparams: List[TypeDef],
vparamss: List[List[ValDef]], tpt: Tree, rhs: Tree) extends ValOrDefDef
/** An abstract type, a type parameter, or a type alias.
*/
case class TypeDef(mods: Modifiers, name: TypeName, tparams: List[TypeDef], rhs: Tree)
extends MemberDef
/** A labelled expression. Not expressible in language syntax, but
* generated by the compiler to simulate while/do-while loops, and
* also by the pattern matcher.
*
* The label acts much like a nested function, where `params` represents
* the incoming parameters. The symbol given to the LabelDef should have
* a MethodType, as if it were a nested function.
*
* Jumps are apply nodes attributed with a label's symbol. The
* arguments from the apply node will be passed to the label and
* assigned to the Idents.
*
* Forward jumps within a block are allowed.
*/
case class LabelDef(name: TermName, params: List[Ident], rhs: Tree)
extends DefTree with TermTree
/** Import selector
*
* Representation of an imported name its optional rename and their optional positions
*
* @param name the imported name
* @param namePos its position or -1 if undefined
* @param rename the name the import is renamed to (== name if no renaming)
* @param renamePos the position of the rename or -1 if undefined
*/
case class ImportSelector(name: Name, namePos: Int, rename: Name, renamePos: Int)
/** Import clause
*
* @param expr
* @param selectors
*/
case class Import(expr: Tree, selectors: List[ImportSelector])
extends SymTree
// The symbol of an Import is an import symbol @see Symbol.newImport
// It's used primarily as a marker to check that the import has been typechecked.
/** Instantiation template of a class or trait
*
* @param parents
* @param body
*/
case class Template(parents: List[Tree], self: ValDef, body: List[Tree])
extends SymTree {
// the symbol of a template is a local dummy. @see Symbol.newLocalDummy
// the owner of the local dummy is the enclosing trait or class.
// the local dummy is itself the owner of any local blocks
// For example:
//
// class C {
// def foo // owner is C
// {
// def bar // owner is local dummy
// }
// System.err.println("TEMPLATE: " + parents)
}
/** Block of expressions (semicolon separated expressions) */
case class Block(stats: List[Tree], expr: Tree)
extends TermTree
/** Case clause in a pattern match, eliminated during explicitouter
* (except for occurrences in switch statements)
*/
case class CaseDef(pat: Tree, guard: Tree, body: Tree)
extends Tree
/** Alternatives of patterns, eliminated by explicitouter, except for
* occurrences in encoded Switch stmt (=remaining Match(CaseDef(...))
*/
case class Alternative(trees: List[Tree])
extends TermTree
/** Repetition of pattern, eliminated by explicitouter */
case class Star(elem: Tree)
extends TermTree
/** Bind of a variable to a rhs pattern, eliminated by explicitouter
*
* @param name
* @param body
*/
case class Bind(name: Name, body: Tree)
extends DefTree
case class UnApply(fun: Tree, args: List[Tree])
extends TermTree
/** Array of expressions, needs to be translated in backend,
*/
case class ArrayValue(elemtpt: Tree, elems: List[Tree])
extends TermTree
/** Anonymous function, eliminated by analyzer */
case class Function(vparams: List[ValDef], body: Tree)
extends TermTree with SymTree
// The symbol of a Function is a synthetic value of name nme.ANON_FUN_NAME
// It is the owner of the function's parameters.
/** Assignment */
case class Assign(lhs: Tree, rhs: Tree)
extends TermTree
/** Conditional expression */
case class If(cond: Tree, thenp: Tree, elsep: Tree)
extends TermTree
/** - Pattern matching expression (before explicitouter)
* - Switch statements (after explicitouter)
*
* After explicitouter, cases will satisfy the following constraints:
*
* - all guards are `EmptyTree`,
* - all patterns will be either `Literal(Constant(x:Int))`
* or `Alternative(lit|...|lit)`
* - except for an "otherwise" branch, which has pattern
* `Ident(nme.WILDCARD)`
*/
case class Match(selector: Tree, cases: List[CaseDef])
extends TermTree
/** Return expression */
case class Return(expr: Tree)
extends TermTree with SymTree
// The symbol of a Return node is the enclosing method.
case class Try(block: Tree, catches: List[CaseDef], finalizer: Tree)
extends TermTree
/** Throw expression */
case class Throw(expr: Tree)
extends TermTree
/** Object instantiation
* One should always use factory method below to build a user level new.
*
* @param tpt a class type
*/
case class New(tpt: Tree) extends TermTree
/** Type annotation, eliminated by explicit outer */
case class Typed(expr: Tree, tpt: Tree)
extends TermTree
/** Common base class for Apply and TypeApply. This could in principle
* be a SymTree, but whether or not a Tree is a SymTree isn't used
* to settle any interesting questions, and it would add a useless
* field to all the instances (useless, since GenericApply forwards to
* the underlying fun.)
*/
abstract class GenericApply extends TermTree {
val fun: Tree
val args: List[Tree]
}
/** Explicit type application.
* @PP: All signs point toward it being a requirement that args.nonEmpty,
* but I can't find that explicitly stated anywhere. Unless your last name
* is odersky, you should probably treat it as true.
*/
case class TypeApply(fun: Tree, args: List[Tree])
extends GenericApply {
override def symbol: Symbol = fun.symbol
override def symbol_=(sym: Symbol) { fun.symbol = sym }
}
/** Value application */
case class Apply(fun: Tree, args: List[Tree])
extends GenericApply {
override def symbol: Symbol = fun.symbol
override def symbol_=(sym: Symbol) { fun.symbol = sym }
}
class ApplyToImplicitArgs(fun: Tree, args: List[Tree]) extends Apply(fun, args)
class ApplyImplicitView(fun: Tree, args: List[Tree]) extends Apply(fun, args)
/** Dynamic value application.
* In a dynamic application q.f(as)
* - q is stored in qual
* - as is stored in args
* - f is stored as the node's symbol field.
*/
case class ApplyDynamic(qual: Tree, args: List[Tree])
extends TermTree with SymTree
// The symbol of an ApplyDynamic is the function symbol of `qual`, or NoSymbol, if there is none.
/** Super reference, qual = corresponding this reference */
case class Super(qual: Tree, mix: TypeName) extends TermTree {
// The symbol of a Super is the class _from_ which the super reference is made.
// For instance in C.super(...), it would be C.
override def symbol: Symbol = qual.symbol
override def symbol_=(sym: Symbol) { qual.symbol = sym }
}
/** Self reference */
case class This(qual: TypeName)
extends TermTree with SymTree
// The symbol of a This is the class to which the this refers.
// For instance in C.this, it would be C.
/** Designator <qualifier> . <name> */
case class Select(qualifier: Tree, name: Name)
extends RefTree
def Select(qualifier: Tree, name: String): Select =
Select(qualifier, newTermName(name))
def Select(qualifier: Tree, sym: Symbol): Select =
Select(qualifier, sym.name) setSymbol sym
/** Identifier <name> */
case class Ident(name: Name) extends RefTree
def Ident(name: String): Ident =
Ident(newTermName(name))
def Ident(sym: Symbol): Ident =
Ident(sym.name) setSymbol sym
class BackQuotedIdent(name: Name) extends Ident(name)
/** Literal */
case class Literal(value: Constant)
extends TermTree {
assert(value ne null)
}
// @deprecated("will be removed and then be re-introduced with changed semantics, use Literal(Constant(x)) instead")
// def Literal(x: Any) = new Literal(Constant(x))
/** A tree that has an annotation attached to it. Only used for annotated types and
* annotation ascriptions, annotations on definitions are stored in the Modifiers.
* Eliminated by typechecker (typedAnnotated), the annotations are then stored in
* an AnnotatedType.
*/
case class Annotated(annot: Tree, arg: Tree) extends Tree
/** Singleton type, eliminated by RefCheck */
case class SingletonTypeTree(ref: Tree)
extends TypTree
/** Type selection <qualifier> # <name>, eliminated by RefCheck */
case class SelectFromTypeTree(qualifier: Tree, name: TypeName)
extends TypTree with RefTree
/** Intersection type <parent1> with ... with <parentN> { <decls> }, eliminated by RefCheck */
case class CompoundTypeTree(templ: Template)
extends TypTree
/** Applied type <tpt> [ <args> ], eliminated by RefCheck */
case class AppliedTypeTree(tpt: Tree, args: List[Tree])
extends TypTree {
override def symbol: Symbol = tpt.symbol
override def symbol_=(sym: Symbol) { tpt.symbol = sym }
}
case class TypeBoundsTree(lo: Tree, hi: Tree)
extends TypTree
case class ExistentialTypeTree(tpt: Tree, whereClauses: List[Tree])
extends TypTree
/** A synthetic tree holding an arbitrary type. Not to be confused with
* with TypTree, the trait for trees that are only used for type trees.
* TypeTree's are inserted in several places, but most notably in
* `RefCheck`, where the arbitrary type trees are all replaced by
* TypeTree's. */
case class TypeTree() extends TypTree {
private var orig: Tree = null
private[scala] var wasEmpty: Boolean = false
override def symbol = if (tpe == null) null else tpe.typeSymbol
override def isEmpty = (tpe eq null) || tpe == NoType
def original: Tree = orig
def setOriginal(tree: Tree): this.type = {
def followOriginal(t: Tree): Tree = t match {
case tt: TypeTree => followOriginal(tt.original)
case t => t
}
orig = followOriginal(tree); setPos(tree.pos);
this
}
override def defineType(tp: Type): this.type = {
wasEmpty = isEmpty
setType(tp)
}
}
def TypeTree(tp: Type): TypeTree = TypeTree() setType tp
/** An empty deferred value definition corresponding to:
* val _: _
* This is used as a placeholder in the `self` parameter Template if there is
* no definition of a self value of self type.
*/
def emptyValDef: ValDef
// ------ traversers, copiers, and transformers ---------------------------------------------
val treeCopy = newLazyTreeCopier
class Traverser {
protected var currentOwner: Symbol = definitions.RootClass
def traverse(tree: Tree): Unit = tree match {
case EmptyTree =>
;
case PackageDef(pid, stats) =>
traverse(pid)
atOwner(tree.symbol.moduleClass) {
traverseTrees(stats)
}
case ClassDef(mods, name, tparams, impl) =>
atOwner(tree.symbol) {
traverseTrees(mods.annotations); traverseTrees(tparams); traverse(impl)
}
case ModuleDef(mods, name, impl) =>
atOwner(tree.symbol.moduleClass) {
traverseTrees(mods.annotations); traverse(impl)
}
case ValDef(mods, name, tpt, rhs) =>
atOwner(tree.symbol) {
traverseTrees(mods.annotations); traverse(tpt); traverse(rhs)
}
case DefDef(mods, name, tparams, vparamss, tpt, rhs) =>
atOwner(tree.symbol) {
traverseTrees(mods.annotations); traverseTrees(tparams); traverseTreess(vparamss); traverse(tpt); traverse(rhs)
}
case TypeDef(mods, name, tparams, rhs) =>
atOwner(tree.symbol) {
traverseTrees(mods.annotations); traverseTrees(tparams); traverse(rhs)
}
case LabelDef(name, params, rhs) =>
traverseTrees(params); traverse(rhs)
case Import(expr, selectors) =>
traverse(expr)
case Annotated(annot, arg) =>
traverse(annot); traverse(arg)
case Template(parents, self, body) =>
traverseTrees(parents)
if (!self.isEmpty) traverse(self)
traverseStats(body, tree.symbol)
case Block(stats, expr) =>
traverseTrees(stats); traverse(expr)
case CaseDef(pat, guard, body) =>
traverse(pat); traverse(guard); traverse(body)
case Alternative(trees) =>
traverseTrees(trees)
case Star(elem) =>
traverse(elem)
case Bind(name, body) =>
traverse(body)
case UnApply(fun, args) =>
traverse(fun); traverseTrees(args)
case ArrayValue(elemtpt, trees) =>
traverse(elemtpt); traverseTrees(trees)
case Function(vparams, body) =>
atOwner(tree.symbol) {
traverseTrees(vparams); traverse(body)
}
case Assign(lhs, rhs) =>
traverse(lhs); traverse(rhs)
case If(cond, thenp, elsep) =>
traverse(cond); traverse(thenp); traverse(elsep)
case Match(selector, cases) =>
traverse(selector); traverseTrees(cases)
case Return(expr) =>
traverse(expr)
case Try(block, catches, finalizer) =>
traverse(block); traverseTrees(catches); traverse(finalizer)
case Throw(expr) =>
traverse(expr)
case New(tpt) =>
traverse(tpt)
case Typed(expr, tpt) =>
traverse(expr); traverse(tpt)
case TypeApply(fun, args) =>
traverse(fun); traverseTrees(args)
case Apply(fun, args) =>
traverse(fun); traverseTrees(args)
case ApplyDynamic(qual, args) =>
traverse(qual); traverseTrees(args)
case Super(qual, _) =>
traverse(qual)
case This(_) =>
;
case Select(qualifier, selector) =>
traverse(qualifier)
case Ident(_) =>
;
case Literal(_) =>
;
case TypeTree() =>
;
case SingletonTypeTree(ref) =>
traverse(ref)
case SelectFromTypeTree(qualifier, selector) =>
traverse(qualifier)
case CompoundTypeTree(templ) =>
traverse(templ)
case AppliedTypeTree(tpt, args) =>
traverse(tpt); traverseTrees(args)
case TypeBoundsTree(lo, hi) =>
traverse(lo); traverse(hi)
case ExistentialTypeTree(tpt, whereClauses) =>
traverse(tpt); traverseTrees(whereClauses)
case _ => xtraverse(this, tree)
}
def traverseTrees(trees: List[Tree]) {
trees foreach traverse
}
def traverseTreess(treess: List[List[Tree]]) {
treess foreach traverseTrees
}
def traverseStats(stats: List[Tree], exprOwner: Symbol) {
stats foreach (stat =>
if (exprOwner != currentOwner) atOwner(exprOwner)(traverse(stat))
else traverse(stat)
)
}
def atOwner(owner: Symbol)(traverse: => Unit) {
val prevOwner = currentOwner
currentOwner = owner
traverse
currentOwner = prevOwner
}
/** Leave apply available in the generic traverser to do something else.
*/
def apply[T <: Tree](tree: T): T = { traverse(tree); tree }
}
protected def xtraverse(traverser: Traverser, tree: Tree): Unit = throw new MatchError(tree)
// to be implemented in subclasses:
type TreeCopier <: TreeCopierOps
def newStrictTreeCopier: TreeCopier
def newLazyTreeCopier: TreeCopier
trait TreeCopierOps {
def ClassDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], impl: Template): ClassDef
def PackageDef(tree: Tree, pid: RefTree, stats: List[Tree]): PackageDef
def ModuleDef(tree: Tree, mods: Modifiers, name: Name, impl: Template): ModuleDef
def ValDef(tree: Tree, mods: Modifiers, name: Name, tpt: Tree, rhs: Tree): ValDef
def DefDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], vparamss: List[List[ValDef]], tpt: Tree, rhs: Tree): DefDef
def TypeDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], rhs: Tree): TypeDef
def LabelDef(tree: Tree, name: Name, params: List[Ident], rhs: Tree): LabelDef
def Import(tree: Tree, expr: Tree, selectors: List[ImportSelector]): Import
def Template(tree: Tree, parents: List[Tree], self: ValDef, body: List[Tree]): Template
def Block(tree: Tree, stats: List[Tree], expr: Tree): Block
def CaseDef(tree: Tree, pat: Tree, guard: Tree, body: Tree): CaseDef
def Alternative(tree: Tree, trees: List[Tree]): Alternative
def Star(tree: Tree, elem: Tree): Star
def Bind(tree: Tree, name: Name, body: Tree): Bind
def UnApply(tree: Tree, fun: Tree, args: List[Tree]): UnApply
def ArrayValue(tree: Tree, elemtpt: Tree, trees: List[Tree]): ArrayValue
def Function(tree: Tree, vparams: List[ValDef], body: Tree): Function
def Assign(tree: Tree, lhs: Tree, rhs: Tree): Assign
def If(tree: Tree, cond: Tree, thenp: Tree, elsep: Tree): If
def Match(tree: Tree, selector: Tree, cases: List[CaseDef]): Match
def Return(tree: Tree, expr: Tree): Return
def Try(tree: Tree, block: Tree, catches: List[CaseDef], finalizer: Tree): Try
def Throw(tree: Tree, expr: Tree): Throw
def New(tree: Tree, tpt: Tree): New
def Typed(tree: Tree, expr: Tree, tpt: Tree): Typed
def TypeApply(tree: Tree, fun: Tree, args: List[Tree]): TypeApply
def Apply(tree: Tree, fun: Tree, args: List[Tree]): Apply
def ApplyDynamic(tree: Tree, qual: Tree, args: List[Tree]): ApplyDynamic
def Super(tree: Tree, qual: Tree, mix: TypeName): Super
def This(tree: Tree, qual: Name): This
def Select(tree: Tree, qualifier: Tree, selector: Name): Select
def Ident(tree: Tree, name: Name): Ident
def Literal(tree: Tree, value: Constant): Literal
def TypeTree(tree: Tree): TypeTree
def Annotated(tree: Tree, annot: Tree, arg: Tree): Annotated
def SingletonTypeTree(tree: Tree, ref: Tree): SingletonTypeTree
def SelectFromTypeTree(tree: Tree, qualifier: Tree, selector: Name): SelectFromTypeTree
def CompoundTypeTree(tree: Tree, templ: Template): CompoundTypeTree
def AppliedTypeTree(tree: Tree, tpt: Tree, args: List[Tree]): AppliedTypeTree
def TypeBoundsTree(tree: Tree, lo: Tree, hi: Tree): TypeBoundsTree
def ExistentialTypeTree(tree: Tree, tpt: Tree, whereClauses: List[Tree]): ExistentialTypeTree
}
class StrictTreeCopier extends TreeCopierOps {
def ClassDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], impl: Template) =
new ClassDef(mods, name.toTypeName, tparams, impl).copyAttrs(tree)
def PackageDef(tree: Tree, pid: RefTree, stats: List[Tree]) =
new PackageDef(pid, stats).copyAttrs(tree)
def ModuleDef(tree: Tree, mods: Modifiers, name: Name, impl: Template) =
new ModuleDef(mods, name.toTermName, impl).copyAttrs(tree)
def ValDef(tree: Tree, mods: Modifiers, name: Name, tpt: Tree, rhs: Tree) =
new ValDef(mods, name.toTermName, tpt, rhs).copyAttrs(tree)
def DefDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], vparamss: List[List[ValDef]], tpt: Tree, rhs: Tree) =
new DefDef(mods, name.toTermName, tparams, vparamss, tpt, rhs).copyAttrs(tree)
def TypeDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], rhs: Tree) =
new TypeDef(mods, name.toTypeName, tparams, rhs).copyAttrs(tree)
def LabelDef(tree: Tree, name: Name, params: List[Ident], rhs: Tree) =
new LabelDef(name.toTermName, params, rhs).copyAttrs(tree)
def Import(tree: Tree, expr: Tree, selectors: List[ImportSelector]) =
new Import(expr, selectors).copyAttrs(tree)
def Template(tree: Tree, parents: List[Tree], self: ValDef, body: List[Tree]) =
new Template(parents, self, body).copyAttrs(tree)
def Block(tree: Tree, stats: List[Tree], expr: Tree) =
new Block(stats, expr).copyAttrs(tree)
def CaseDef(tree: Tree, pat: Tree, guard: Tree, body: Tree) =
new CaseDef(pat, guard, body).copyAttrs(tree)
def Alternative(tree: Tree, trees: List[Tree]) =
new Alternative(trees).copyAttrs(tree)
def Star(tree: Tree, elem: Tree) =
new Star(elem).copyAttrs(tree)
def Bind(tree: Tree, name: Name, body: Tree) =
new Bind(name, body).copyAttrs(tree)
def UnApply(tree: Tree, fun: Tree, args: List[Tree]) =
new UnApply(fun, args).copyAttrs(tree)
def ArrayValue(tree: Tree, elemtpt: Tree, trees: List[Tree]) =
new ArrayValue(elemtpt, trees).copyAttrs(tree)
def Function(tree: Tree, vparams: List[ValDef], body: Tree) =
new Function(vparams, body).copyAttrs(tree)
def Assign(tree: Tree, lhs: Tree, rhs: Tree) =
new Assign(lhs, rhs).copyAttrs(tree)
def If(tree: Tree, cond: Tree, thenp: Tree, elsep: Tree) =
new If(cond, thenp, elsep).copyAttrs(tree)
def Match(tree: Tree, selector: Tree, cases: List[CaseDef]) =
new Match(selector, cases).copyAttrs(tree)
def Return(tree: Tree, expr: Tree) =
new Return(expr).copyAttrs(tree)
def Try(tree: Tree, block: Tree, catches: List[CaseDef], finalizer: Tree) =
new Try(block, catches, finalizer).copyAttrs(tree)
def Throw(tree: Tree, expr: Tree) =
new Throw(expr).copyAttrs(tree)
def New(tree: Tree, tpt: Tree) =
new New(tpt).copyAttrs(tree)
def Typed(tree: Tree, expr: Tree, tpt: Tree) =
new Typed(expr, tpt).copyAttrs(tree)
def TypeApply(tree: Tree, fun: Tree, args: List[Tree]) =
new TypeApply(fun, args).copyAttrs(tree)
def Apply(tree: Tree, fun: Tree, args: List[Tree]) =
(tree match {
case _: ApplyToImplicitArgs => new ApplyToImplicitArgs(fun, args)
case _: ApplyImplicitView => new ApplyImplicitView(fun, args)
case _ => new Apply(fun, args)
}).copyAttrs(tree)
def ApplyDynamic(tree: Tree, qual: Tree, args: List[Tree]) =
new ApplyDynamic(qual, args).copyAttrs(tree)
def Super(tree: Tree, qual: Tree, mix: TypeName) =
new Super(qual, mix).copyAttrs(tree)
def This(tree: Tree, qual: Name) =
new This(qual.toTypeName).copyAttrs(tree)
def Select(tree: Tree, qualifier: Tree, selector: Name) =
new Select(qualifier, selector).copyAttrs(tree)
def Ident(tree: Tree, name: Name) =
new Ident(name).copyAttrs(tree)
def Literal(tree: Tree, value: Constant) =
new Literal(value).copyAttrs(tree)
def TypeTree(tree: Tree) =
new TypeTree().copyAttrs(tree)
def Annotated(tree: Tree, annot: Tree, arg: Tree) =
new Annotated(annot, arg).copyAttrs(tree)
def SingletonTypeTree(tree: Tree, ref: Tree) =
new SingletonTypeTree(ref).copyAttrs(tree)
def SelectFromTypeTree(tree: Tree, qualifier: Tree, selector: Name) =
new SelectFromTypeTree(qualifier, selector.toTypeName).copyAttrs(tree)
def CompoundTypeTree(tree: Tree, templ: Template) =
new CompoundTypeTree(templ).copyAttrs(tree)
def AppliedTypeTree(tree: Tree, tpt: Tree, args: List[Tree]) =
new AppliedTypeTree(tpt, args).copyAttrs(tree)
def TypeBoundsTree(tree: Tree, lo: Tree, hi: Tree) =
new TypeBoundsTree(lo, hi).copyAttrs(tree)
def ExistentialTypeTree(tree: Tree, tpt: Tree, whereClauses: List[Tree]) =
new ExistentialTypeTree(tpt, whereClauses).copyAttrs(tree)
}
class LazyTreeCopier extends TreeCopierOps {
val treeCopy: TreeCopier = newStrictTreeCopier
def ClassDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], impl: Template) = tree match {
case t @ ClassDef(mods0, name0, tparams0, impl0)
if (mods0 == mods) && (name0 == name) && (tparams0 == tparams) && (impl0 == impl) => t
case _ => treeCopy.ClassDef(tree, mods, name, tparams, impl)
}
def PackageDef(tree: Tree, pid: RefTree, stats: List[Tree]) = tree match {
case t @ PackageDef(pid0, stats0)
if (pid0 == pid) && (stats0 == stats) => t
case _ => treeCopy.PackageDef(tree, pid, stats)
}
def ModuleDef(tree: Tree, mods: Modifiers, name: Name, impl: Template) = tree match {
case t @ ModuleDef(mods0, name0, impl0)
if (mods0 == mods) && (name0 == name) && (impl0 == impl) => t
case _ => treeCopy.ModuleDef(tree, mods, name, impl)
}
def ValDef(tree: Tree, mods: Modifiers, name: Name, tpt: Tree, rhs: Tree) = tree match {
case t @ ValDef(mods0, name0, tpt0, rhs0)
if (mods0 == mods) && (name0 == name) && (tpt0 == tpt) && (rhs0 == rhs) => t
case _ => treeCopy.ValDef(tree, mods, name, tpt, rhs)
}
def DefDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], vparamss: List[List[ValDef]], tpt: Tree, rhs: Tree) = tree match {
case t @ DefDef(mods0, name0, tparams0, vparamss0, tpt0, rhs0)
if (mods0 == mods) && (name0 == name) && (tparams0 == tparams) &&
(vparamss0 == vparamss) && (tpt0 == tpt) && (rhs == rhs0) => t
case _ => treeCopy.DefDef(tree, mods, name, tparams, vparamss, tpt, rhs)
}
def TypeDef(tree: Tree, mods: Modifiers, name: Name, tparams: List[TypeDef], rhs: Tree) = tree match {
case t @ TypeDef(mods0, name0, tparams0, rhs0)
if (mods0 == mods) && (name0 == name) && (tparams0 == tparams) && (rhs0 == rhs) => t
case _ => treeCopy.TypeDef(tree, mods, name, tparams, rhs)
}
def LabelDef(tree: Tree, name: Name, params: List[Ident], rhs: Tree) = tree match {
case t @ LabelDef(name0, params0, rhs0)
if (name0 == name) && (params0 == params) && (rhs0 == rhs) => t
case _ => treeCopy.LabelDef(tree, name, params, rhs)
}
def Import(tree: Tree, expr: Tree, selectors: List[ImportSelector]) = tree match {
case t @ Import(expr0, selectors0)
if (expr0 == expr) && (selectors0 == selectors) => t
case _ => treeCopy.Import(tree, expr, selectors)
}
def Template(tree: Tree, parents: List[Tree], self: ValDef, body: List[Tree]) = tree match {
case t @ Template(parents0, self0, body0)
if (parents0 == parents) && (self0 == self) && (body0 == body) => t
case _ => treeCopy.Template(tree, parents, self, body)
}
def Block(tree: Tree, stats: List[Tree], expr: Tree) = tree match {
case t @ Block(stats0, expr0)
if ((stats0 == stats) && (expr0 == expr)) => t
case _ => treeCopy.Block(tree, stats, expr)
}
def CaseDef(tree: Tree, pat: Tree, guard: Tree, body: Tree) = tree match {
case t @ CaseDef(pat0, guard0, body0)
if (pat0 == pat) && (guard0 == guard) && (body0 == body) => t
case _ => treeCopy.CaseDef(tree, pat, guard, body)
}
def Alternative(tree: Tree, trees: List[Tree]) = tree match {
case t @ Alternative(trees0)
if trees0 == trees => t
case _ => treeCopy.Alternative(tree, trees)
}
def Star(tree: Tree, elem: Tree) = tree match {
case t @ Star(elem0)
if elem0 == elem => t
case _ => treeCopy.Star(tree, elem)
}
def Bind(tree: Tree, name: Name, body: Tree) = tree match {
case t @ Bind(name0, body0)
if (name0 == name) && (body0 == body) => t
case _ => treeCopy.Bind(tree, name, body)
}
def UnApply(tree: Tree, fun: Tree, args: List[Tree]) = tree match {
case t @ UnApply(fun0, args0)
if (fun0 == fun) && (args0 == args) => t
case _ => treeCopy.UnApply(tree, fun, args)
}
def ArrayValue(tree: Tree, elemtpt: Tree, trees: List[Tree]) = tree match {
case t @ ArrayValue(elemtpt0, trees0)
if (elemtpt0 == elemtpt) && (trees0 == trees) => t
case _ => treeCopy.ArrayValue(tree, elemtpt, trees)
}
def Function(tree: Tree, vparams: List[ValDef], body: Tree) = tree match {
case t @ Function(vparams0, body0)
if (vparams0 == vparams) && (body0 == body) => t
case _ => treeCopy.Function(tree, vparams, body)
}
def Assign(tree: Tree, lhs: Tree, rhs: Tree) = tree match {
case t @ Assign(lhs0, rhs0)
if (lhs0 == lhs) && (rhs0 == rhs) => t
case _ => treeCopy.Assign(tree, lhs, rhs)
}
def If(tree: Tree, cond: Tree, thenp: Tree, elsep: Tree) = tree match {
case t @ If(cond0, thenp0, elsep0)
if (cond0 == cond) && (thenp0 == thenp) && (elsep0 == elsep) => t
case _ => treeCopy.If(tree, cond, thenp, elsep)
}
def Match(tree: Tree, selector: Tree, cases: List[CaseDef]) = tree match {
case t @ Match(selector0, cases0)
if (selector0 == selector) && (cases0 == cases) => t
case _ => treeCopy.Match(tree, selector, cases)
}
def Return(tree: Tree, expr: Tree) = tree match {
case t @ Return(expr0)
if expr0 == expr => t
case _ => treeCopy.Return(tree, expr)
}
def Try(tree: Tree, block: Tree, catches: List[CaseDef], finalizer: Tree) = tree match {
case t @ Try(block0, catches0, finalizer0)
if (block0 == block) && (catches0 == catches) && (finalizer0 == finalizer) => t
case _ => treeCopy.Try(tree, block, catches, finalizer)
}
def Throw(tree: Tree, expr: Tree) = tree match {
case t @ Throw(expr0)
if expr0 == expr => t
case _ => treeCopy.Throw(tree, expr)
}
def New(tree: Tree, tpt: Tree) = tree match {
case t @ New(tpt0)
if tpt0 == tpt => t
case _ => treeCopy.New(tree, tpt)
}
def Typed(tree: Tree, expr: Tree, tpt: Tree) = tree match {
case t @ Typed(expr0, tpt0)
if (expr0 == expr) && (tpt0 == tpt) => t
case _ => treeCopy.Typed(tree, expr, tpt)
}
def TypeApply(tree: Tree, fun: Tree, args: List[Tree]) = tree match {
case t @ TypeApply(fun0, args0)
if (fun0 == fun) && (args0 == args) => t
case _ => treeCopy.TypeApply(tree, fun, args)
}
def Apply(tree: Tree, fun: Tree, args: List[Tree]) = tree match {
case t @ Apply(fun0, args0)
if (fun0 == fun) && (args0 == args) => t
case _ => treeCopy.Apply(tree, fun, args)
}
def ApplyDynamic(tree: Tree, qual: Tree, args: List[Tree]) = tree match {
case t @ ApplyDynamic(qual0, args0)
if (qual0 == qual) && (args0 == args) => t
case _ => treeCopy.ApplyDynamic(tree, qual, args)
}
def Super(tree: Tree, qual: Tree, mix: TypeName) = tree match {
case t @ Super(qual0, mix0)
if (qual0 == qual) && (mix0 == mix) => t
case _ => treeCopy.Super(tree, qual, mix)
}
def This(tree: Tree, qual: Name) = tree match {
case t @ This(qual0)
if qual0 == qual => t
case _ => treeCopy.This(tree, qual)
}
def Select(tree: Tree, qualifier: Tree, selector: Name) = tree match {
case t @ Select(qualifier0, selector0)
if (qualifier0 == qualifier) && (selector0 == selector) => t
case _ => treeCopy.Select(tree, qualifier, selector)
}
def Ident(tree: Tree, name: Name) = tree match {
case t @ Ident(name0)
if name0 == name => t
case _ => treeCopy.Ident(tree, name)
}
def Literal(tree: Tree, value: Constant) = tree match {
case t @ Literal(value0)
if value0 == value => t
case _ => treeCopy.Literal(tree, value)
}
def TypeTree(tree: Tree) = tree match {
case t @ TypeTree() => t
case _ => treeCopy.TypeTree(tree)
}
def Annotated(tree: Tree, annot: Tree, arg: Tree) = tree match {
case t @ Annotated(annot0, arg0)
if (annot0==annot) => t
case _ => treeCopy.Annotated(tree, annot, arg)
}
def SingletonTypeTree(tree: Tree, ref: Tree) = tree match {
case t @ SingletonTypeTree(ref0)
if ref0 == ref => t
case _ => treeCopy.SingletonTypeTree(tree, ref)
}
def SelectFromTypeTree(tree: Tree, qualifier: Tree, selector: Name) = tree match {
case t @ SelectFromTypeTree(qualifier0, selector0)
if (qualifier0 == qualifier) && (selector0 == selector) => t
case _ => treeCopy.SelectFromTypeTree(tree, qualifier, selector)
}
def CompoundTypeTree(tree: Tree, templ: Template) = tree match {
case t @ CompoundTypeTree(templ0)
if templ0 == templ => t
case _ => treeCopy.CompoundTypeTree(tree, templ)
}
def AppliedTypeTree(tree: Tree, tpt: Tree, args: List[Tree]) = tree match {
case t @ AppliedTypeTree(tpt0, args0)
if (tpt0 == tpt) && (args0 == args) => t
case _ => treeCopy.AppliedTypeTree(tree, tpt, args)
}
def TypeBoundsTree(tree: Tree, lo: Tree, hi: Tree) = tree match {
case t @ TypeBoundsTree(lo0, hi0)
if (lo0 == lo) && (hi0 == hi) => t
case _ => treeCopy.TypeBoundsTree(tree, lo, hi)
}
def ExistentialTypeTree(tree: Tree, tpt: Tree, whereClauses: List[Tree]) = tree match {
case t @ ExistentialTypeTree(tpt0, whereClauses0)
if (tpt0 == tpt) && (whereClauses0 == whereClauses) => t
case _ => treeCopy.ExistentialTypeTree(tree, tpt, whereClauses)
}
}
abstract class Transformer {
val treeCopy: TreeCopier = newLazyTreeCopier
protected var currentOwner: Symbol = definitions.RootClass
protected def currentMethod = currentOwner.enclMethod
protected def currentClass = currentOwner.enclClass
protected def currentPackage = currentOwner.toplevelClass.owner
def transform(tree: Tree): Tree = tree match {
case EmptyTree =>
tree
case PackageDef(pid, stats) =>
treeCopy.PackageDef(
tree, transform(pid).asInstanceOf[RefTree],
atOwner(tree.symbol.moduleClass) {
transformStats(stats, currentOwner)
}
)
case ClassDef(mods, name, tparams, impl) =>
atOwner(tree.symbol) {
treeCopy.ClassDef(tree, transformModifiers(mods), name,
transformTypeDefs(tparams), transformTemplate(impl))
}
case ModuleDef(mods, name, impl) =>
atOwner(tree.symbol.moduleClass) {
treeCopy.ModuleDef(tree, transformModifiers(mods),
name, transformTemplate(impl))
}
case ValDef(mods, name, tpt, rhs) =>
atOwner(tree.symbol) {
treeCopy.ValDef(tree, transformModifiers(mods),
name, transform(tpt), transform(rhs))
}
case DefDef(mods, name, tparams, vparamss, tpt, rhs) =>
atOwner(tree.symbol) {
treeCopy.DefDef(tree, transformModifiers(mods), name,
transformTypeDefs(tparams), transformValDefss(vparamss),
transform(tpt), transform(rhs))
}
case TypeDef(mods, name, tparams, rhs) =>
atOwner(tree.symbol) {
treeCopy.TypeDef(tree, transformModifiers(mods), name,
transformTypeDefs(tparams), transform(rhs))
}
case LabelDef(name, params, rhs) =>
treeCopy.LabelDef(tree, name, transformIdents(params), transform(rhs)) //bq: Martin, once, atOwner(...) works, also change `LamdaLifter.proxy'
case Import(expr, selectors) =>
treeCopy.Import(tree, transform(expr), selectors)
case Template(parents, self, body) =>
treeCopy.Template(tree, transformTrees(parents), transformValDef(self), transformStats(body, tree.symbol))
case Block(stats, expr) =>
treeCopy.Block(tree, transformStats(stats, currentOwner), transform(expr))
case CaseDef(pat, guard, body) =>
treeCopy.CaseDef(tree, transform(pat), transform(guard), transform(body))
case Alternative(trees) =>
treeCopy.Alternative(tree, transformTrees(trees))
case Star(elem) =>
treeCopy.Star(tree, transform(elem))
case Bind(name, body) =>
treeCopy.Bind(tree, name, transform(body))
case UnApply(fun, args) =>
treeCopy.UnApply(tree, fun, transformTrees(args)) // bq: see test/.../unapplyContexts2.scala
case ArrayValue(elemtpt, trees) =>
treeCopy.ArrayValue(tree, transform(elemtpt), transformTrees(trees))
case Function(vparams, body) =>
atOwner(tree.symbol) {
treeCopy.Function(tree, transformValDefs(vparams), transform(body))
}
case Assign(lhs, rhs) =>
treeCopy.Assign(tree, transform(lhs), transform(rhs))
case If(cond, thenp, elsep) =>
treeCopy.If(tree, transform(cond), transform(thenp), transform(elsep))
case Match(selector, cases) =>
treeCopy.Match(tree, transform(selector), transformCaseDefs(cases))
case Return(expr) =>
treeCopy.Return(tree, transform(expr))
case Try(block, catches, finalizer) =>
treeCopy.Try(tree, transform(block), transformCaseDefs(catches), transform(finalizer))
case Throw(expr) =>
treeCopy.Throw(tree, transform(expr))
case New(tpt) =>
treeCopy.New(tree, transform(tpt))
case Typed(expr, tpt) =>
treeCopy.Typed(tree, transform(expr), transform(tpt))
case TypeApply(fun, args) =>
treeCopy.TypeApply(tree, transform(fun), transformTrees(args))
case Apply(fun, args) =>
treeCopy.Apply(tree, transform(fun), transformTrees(args))
case ApplyDynamic(qual, args) =>
treeCopy.ApplyDynamic(tree, transform(qual), transformTrees(args))
case Super(qual, mix) =>
treeCopy.Super(tree, transform(qual), mix)
case This(qual) =>
treeCopy.This(tree, qual)
case Select(qualifier, selector) =>
treeCopy.Select(tree, transform(qualifier), selector)
case Ident(name) =>
treeCopy.Ident(tree, name)
case Literal(value) =>
treeCopy.Literal(tree, value)
case TypeTree() =>
treeCopy.TypeTree(tree)
case Annotated(annot, arg) =>
treeCopy.Annotated(tree, transform(annot), transform(arg))
case SingletonTypeTree(ref) =>
treeCopy.SingletonTypeTree(tree, transform(ref))
case SelectFromTypeTree(qualifier, selector) =>
treeCopy.SelectFromTypeTree(tree, transform(qualifier), selector)
case CompoundTypeTree(templ) =>
treeCopy.CompoundTypeTree(tree, transformTemplate(templ))
case AppliedTypeTree(tpt, args) =>
treeCopy.AppliedTypeTree(tree, transform(tpt), transformTrees(args))
case TypeBoundsTree(lo, hi) =>
treeCopy.TypeBoundsTree(tree, transform(lo), transform(hi))
case ExistentialTypeTree(tpt, whereClauses) =>
treeCopy.ExistentialTypeTree(tree, transform(tpt), transformTrees(whereClauses))
case _ =>
xtransform(this, tree)
}
def transformTrees(trees: List[Tree]): List[Tree] =
trees mapConserve (transform(_))
def transformTemplate(tree: Template): Template =
transform(tree: Tree).asInstanceOf[Template]
def transformTypeDefs(trees: List[TypeDef]): List[TypeDef] =
trees mapConserve (tree => transform(tree).asInstanceOf[TypeDef])
def transformValDef(tree: ValDef): ValDef =
if (tree.isEmpty) tree else transform(tree).asInstanceOf[ValDef]
def transformValDefs(trees: List[ValDef]): List[ValDef] =
trees mapConserve (transformValDef(_))
def transformValDefss(treess: List[List[ValDef]]): List[List[ValDef]] =
treess mapConserve (transformValDefs(_))
def transformCaseDefs(trees: List[CaseDef]): List[CaseDef] =
trees mapConserve (tree => transform(tree).asInstanceOf[CaseDef])
def transformIdents(trees: List[Ident]): List[Ident] =
trees mapConserve (tree => transform(tree).asInstanceOf[Ident])
def transformStats(stats: List[Tree], exprOwner: Symbol): List[Tree] =
stats mapConserve (stat =>
if (exprOwner != currentOwner && stat.isTerm) atOwner(exprOwner)(transform(stat))
else transform(stat)) filter (EmptyTree !=)
def transformModifiers(mods: Modifiers): Modifiers =
mods.mapAnnotations(transformTrees)
def atOwner[A](owner: Symbol)(trans: => A): A = {
val prevOwner = currentOwner
currentOwner = owner
val result = trans
currentOwner = prevOwner
result
}
}
protected def xtransform(transformer: Transformer, tree: Tree): Tree = throw new MatchError(tree)
class ForeachTreeTraverser(f: Tree => Unit) extends Traverser {
override def traverse(t: Tree) {
f(t)
super.traverse(t)
}
}
class FilterTreeTraverser(p: Tree => Boolean) extends Traverser {
val hits = new ListBuffer[Tree]
override def traverse(t: Tree) {
if (p(t)) hits += t
super.traverse(t)
}
}
class FindTreeTraverser(p: Tree => Boolean) extends Traverser {
var result: Option[Tree] = None
override def traverse(t: Tree) {
if (result.isEmpty) {
if (p(t)) result = Some(t)
super.traverse(t)
}
}
}
protected def duplicateTree(tree: Tree): Tree
/* A standard pattern match
case EmptyTree =>
case PackageDef(pid, stats) =>
// package pid { stats }
case ClassDef(mods, name, tparams, impl) =>
// mods class name [tparams] impl where impl = extends parents { defs }
case ModuleDef(mods, name, impl) => (eliminated by refcheck)
// mods object name impl where impl = extends parents { defs }
case ValDef(mods, name, tpt, rhs) =>
// mods val name: tpt = rhs
// note missing type information is expressed by tpt = TypeTree()
case DefDef(mods, name, tparams, vparamss, tpt, rhs) =>
// mods def name[tparams](vparams_1)...(vparams_n): tpt = rhs
// note missing type information is expressed by tpt = TypeTree()
case TypeDef(mods, name, tparams, rhs) => (eliminated by erasure)
// mods type name[tparams] = rhs
// mods type name[tparams] >: lo <: hi, where lo, hi are in a TypeBoundsTree,
and DEFERRED is set in mods
case LabelDef(name, params, rhs) =>
// used for tailcalls and like
// while/do are desugared to label defs as follows:
// while (cond) body ==> LabelDef($L, List(), if (cond) { body; L$() } else ())
// do body while (cond) ==> LabelDef($L, List(), body; if (cond) L$() else ())
case Import(expr, selectors) => (eliminated by typecheck)
// import expr.{selectors}
// Selectors are a list of pairs of names (from, to).
// The last (and maybe only name) may be a nme.WILDCARD
// for instance
// import qual.{x, y => z, _} would be represented as
// Import(qual, List(("x", "x"), ("y", "z"), (WILDCARD, null)))
case Template(parents, self, body) =>
// extends parents { self => body }
// if self is missing it is represented as emptyValDef
case Block(stats, expr) =>
// { stats; expr }
case CaseDef(pat, guard, body) => (eliminated by transmatch/explicitouter)
// case pat if guard => body
case Alternative(trees) => (eliminated by transmatch/explicitouter)
// pat1 | ... | patn
case Star(elem) => (eliminated by transmatch/explicitouter)
// pat*
case Bind(name, body) => (eliminated by transmatch/explicitouter)
// name @ pat
case UnApply(fun: Tree, args) (introduced by typer, eliminated by transmatch/explicitouter)
// used for unapply's
case ArrayValue(elemtpt, trees) => (introduced by uncurry)
// used to pass arguments to vararg arguments
// for instance, printf("%s%d", foo, 42) is translated to after uncurry to:
// Apply(
// Ident("printf"),
// Literal("%s%d"),
// ArrayValue(<Any>, List(Ident("foo"), Literal(42))))
case Function(vparams, body) => (eliminated by lambdaLift)
// vparams => body where vparams:List[ValDef]
case Assign(lhs, rhs) =>
// lhs = rhs
case If(cond, thenp, elsep) =>
// if (cond) thenp else elsep
case Match(selector, cases) =>
// selector match { cases }
case Return(expr) =>
// return expr
case Try(block, catches, finalizer) =>
// try block catch { catches } finally finalizer where catches: List[CaseDef]
case Throw(expr) =>
// throw expr
case New(tpt) =>
// new tpt always in the context: (new tpt).<init>[targs](args)
case Typed(expr, tpt) => (eliminated by erasure)
// expr: tpt
case TypeApply(fun, args) =>
// fun[args]
case Apply(fun, args) =>
// fun(args)
// for instance fun[targs](args) is expressed as Apply(TypeApply(fun, targs), args)
case ApplyDynamic(qual, args) (introduced by erasure, eliminated by cleanup)
// fun(args)
case Super(qual, mix) =>
// qual.super[mix] if qual and/or mix is empty, ther are tpnme.EMPTY
case This(qual) =>
// qual.this
case Select(qualifier, selector) =>
// qualifier.selector
case Ident(name) =>
// name
// note: type checker converts idents that refer to enclosing fields or methods
// to selects; name ==> this.name
case Literal(value) =>
// value
case TypeTree() => (introduced by refcheck)
// a type that's not written out, but given in the tpe attribute
case Annotated(annot, arg) => (eliminated by typer)
// arg @annot for types, arg: @annot for exprs
case SingletonTypeTree(ref) => (eliminated by uncurry)
// ref.type
case SelectFromTypeTree(qualifier, selector) => (eliminated by uncurry)
// qualifier # selector, a path-dependent type p.T is expressed as p.type # T
case CompoundTypeTree(templ: Template) => (eliminated by uncurry)
// parent1 with ... with parentN { refinement }
case AppliedTypeTree(tpt, args) => (eliminated by uncurry)
// tpt[args]
case TypeBoundsTree(lo, hi) => (eliminated by uncurry)
// >: lo <: hi
case ExistentialTypeTree(tpt, whereClauses) => (eliminated by uncurry)
// tpt forSome { whereClauses }
*/
}
