A minimal SBT build.

Doesn't execute tests yet.

3 files changed, 0 insertions, 690 deletions

diff --git a/src/async/library/scala/async/Async.scala b/src/async/library/scala/async/Async.scala
deleted file mode 100644
index 2c81bc3..0000000
--- a/src/async/library/scala/async/Async.scala
+++ /dev/null
@@ -1,135 +0,0 @@
-/**
- * Copyright (C) 2012 Typesafe Inc. <http://www.typesafe.com>
- */
-package scala.async
-
-import language.experimental.macros
-
-import scala.reflect.macros.Context
-import scala.collection.mutable.ListBuffer
-import scala.concurrent.{ Future, Promise, ExecutionContext, future }
-import ExecutionContext.Implicits.global
-import scala.util.control.NonFatal
-import scala.util.continuations.{ shift, reset, cpsParam }
-
-/* Extending `ControlThrowable`, by default, also avoids filling in the stack trace. */
-class FallbackToCpsException extends scala.util.control.ControlThrowable
-
-/*
- * @author Philipp Haller
- */
-object Async extends AsyncUtils {
-
-  def async[T](body: T): Future[T] = macro asyncImpl[T]
-  
-  def await[T](awaitable: Future[T]): T = ???
-  
-  /* Fall back for `await` when it is called at an unsupported position.
-   */
-  def awaitCps[T, U](awaitable: Future[T], p: Promise[U]): T @cpsParam[U, Unit] =
-    shift {
-      (k: (T => U)) =>
-        awaitable onComplete {
-          case tr => p.success(k(tr.get))
-        }
-    }
-  
-  def asyncImpl[T: c.WeakTypeTag](c: Context)(body: c.Expr[T]): c.Expr[Future[T]] = {
-    import c.universe._
-    import Flag._
-    
-    val builder = new ExprBuilder[c.type](c)
-    val awaitMethod = awaitSym(c)
-    
-    try {
-      body.tree match {
-        case Block(stats, expr) =>
-          val asyncBlockBuilder = new builder.AsyncBlockBuilder(stats, expr, 0, 1000, 1000, Map())
-
-          vprintln(s"states of current method:")
-          asyncBlockBuilder.asyncStates foreach vprintln
-
-          val handlerExpr = asyncBlockBuilder.mkCombinedHandlerExpr()
-
-          vprintln(s"GENERATED handler expr:")
-          vprintln(handlerExpr)
-
-          val handlerForLastState: c.Expr[PartialFunction[Int, Unit]] = {
-            val tree = Apply(Select(Ident("result"), newTermName("success")),
-              List(asyncBlockBuilder.asyncStates.last.body))
-            builder.mkHandler(asyncBlockBuilder.asyncStates.last.state, c.Expr[Unit](tree))
-          }
-
-          vprintln("GENERATED handler for last state:")
-          vprintln(handlerForLastState)
-
-          val localVarTrees = asyncBlockBuilder.asyncStates.init.flatMap(_.allVarDefs).toList
-          
-          /*
-            def resume(): Unit = {
-              try {
-                (handlerExpr.splice orElse handlerForLastState.splice)(state)
-              } catch {
-                case NonFatal(t) => result.failure(t)
-              }
-            }
-           */
-          val resumeFunTree: c.Tree = DefDef(Modifiers(), newTermName("resume"), List(), List(List()), Ident(definitions.UnitClass),
-            Try(Apply(Select(
-              Apply(Select(handlerExpr.tree, newTermName("orElse")), List(handlerForLastState.tree)),
-              newTermName("apply")), List(Ident(newTermName("state")))),
-              List(
-                CaseDef(
-                  Apply(Select(Select(Select(Ident(newTermName("scala")), newTermName("util")), newTermName("control")), newTermName("NonFatal")), List(Bind(newTermName("t"), Ident(nme.WILDCARD)))),
-                  EmptyTree,
-                  Block(List(
-                    Apply(Select(Ident(newTermName("result")), newTermName("failure")), List(Ident(newTermName("t"))))),
-                    Literal(Constant(()))))), EmptyTree))
-          
-          reify {
-            val result = Promise[T]()
-            var state = 0
-            future {
-              c.Expr(Block(
-                localVarTrees :+ resumeFunTree,
-                Apply(Ident(newTermName("resume")), List()))).splice
-            }
-            result.future
-          }
-
-        case _ =>
-          // issue error message
-          reify {
-            sys.error("expression not supported by async")
-          }
-      }
-    } catch {
-      case _: FallbackToCpsException =>
-        // replace `await` invocations with `awaitCps` invocations
-        val awaitReplacer = new Transformer {
-          val awaitCpsMethod = awaitCpsSym(c)
-          override def transform(tree: Tree): Tree = tree match {
-            case Apply(fun @ TypeApply(_, List(futArgTpt)), args) if fun.symbol == awaitMethod =>
-              val typeApp = treeCopy.TypeApply(fun, Ident(awaitCpsMethod), List(TypeTree(futArgTpt.tpe), TypeTree(body.tree.tpe)))
-              treeCopy.Apply(tree, typeApp, args.map(arg => c.resetAllAttrs(arg.duplicate)) :+ Ident(newTermName("p")))
-              
-            case _ =>
-              super.transform(tree)
-          }
-        }
-        
-        val newBody = awaitReplacer.transform(body.tree)
-        
-        reify {
-          val p = Promise[T]()
-          future {
-            reset {
-              c.Expr(c.resetAllAttrs(newBody.duplicate)).asInstanceOf[c.Expr[T]].splice
-            }
-          }
-          p.future
-        }
-    }
-  }
-
-}
diff --git a/src/async/library/scala/async/AsyncUtils.scala b/src/async/library/scala/async/AsyncUtils.scala
deleted file mode 100644
index 19e9d92..0000000
--- a/src/async/library/scala/async/AsyncUtils.scala
+++ /dev/null
@@ -1,36 +0,0 @@
-/**
- * Copyright (C) 2012 Typesafe Inc. <http://www.typesafe.com>
- */
-package scala.async
-
-import scala.reflect.macros.Context
-
-/*
- * @author Philipp Haller
- */
-trait AsyncUtils {
-
-  val verbose = false
-  
-  protected def vprintln(s: Any): Unit = if (verbose)
-    println("[async] "+s)
-  
-  /* Symbol of the `Async.await` method in context `c`.
-   */
-  protected def awaitSym(c: Context): c.universe.Symbol = {
-    val asyncMod = c.mirror.staticModule("scala.async.Async")
-    val tpe = asyncMod.moduleClass.asType.toType
-    tpe.member(c.universe.newTermName("await"))
-  }
-  
-  protected def awaitCpsSym(c: Context): c.universe.Symbol = {
-    val asyncMod = c.mirror.staticModule("scala.async.Async")
-    val tpe = asyncMod.moduleClass.asType.toType
-    tpe.member(c.universe.newTermName("awaitCps"))
-  }
-  
-  private var cnt = 0
-  protected[async] def freshString(prefix: String): String =
-    prefix + "$async$" + { cnt += 1; cnt }
-
-}
diff --git a/src/async/library/scala/async/ExprBuilder.scala b/src/async/library/scala/async/ExprBuilder.scala
deleted file mode 100644
index b7d6446..0000000
--- a/src/async/library/scala/async/ExprBuilder.scala
+++ /dev/null
@@ -1,519 +0,0 @@
-/**
- * Copyright (C) 2012 Typesafe Inc. <http://www.typesafe.com>
- */
-package scala.async
-
-import scala.reflect.macros.Context
-import scala.collection.mutable.{ ListBuffer, Builder }
-
-/*
- * @author Philipp Haller
- */
-class ExprBuilder[C <: Context with Singleton](val c: C) extends AsyncUtils {
-  builder =>
-  
-  import c.universe._
-  import Flag._
-  
-  private val awaitMethod = awaitSym(c)
-  
-  /* Make a partial function literal handling case #num:
-   * 
-   *     {
-   *       case any if any == num => rhs
-   *     }
-   */
-  def mkHandler(num: Int, rhs: c.Expr[Unit]): c.Expr[PartialFunction[Int, Unit]] = {
-/*
-    val numLiteral = c.Expr[Int](Literal(Constant(num)))
-    
-    reify(new PartialFunction[Int, Unit] {
-      def isDefinedAt(`x$1`: Int) =
-        `x$1` == numLiteral.splice
-      def apply(`x$1`: Int) = `x$1` match {
-        case any: Int if any == numLiteral.splice =>
-          rhs.splice
-      }
-    })
-*/
-    val rhsTree = c.resetAllAttrs(rhs.tree.duplicate)
-    val handlerTree = mkHandlerTree(num, rhsTree)
-    c.Expr(handlerTree).asInstanceOf[c.Expr[PartialFunction[Int, Unit]]]
-  }
-  
-  def mkIncrStateTree(): c.Tree =
-    Assign(
-      Ident(newTermName("state")),
-      Apply(Select(Ident(newTermName("state")), newTermName("$plus")), List(Literal(Constant(1)))))
-  
-  def mkStateTree(nextState: Int): c.Tree =
-    Assign(
-      Ident(newTermName("state")),
-      Literal(Constant(nextState)))
-  
-  def mkVarDefTree(resultType: c.universe.Type, resultName: c.universe.TermName): c.Tree = {
-    val rhs =
-      if (resultType <:< definitions.IntTpe) Literal(Constant(0))
-      else if (resultType <:< definitions.LongTpe) Literal(Constant(0L))
-      else if (resultType <:< definitions.BooleanTpe) Literal(Constant(false))
-      else Literal(Constant(null))
-    ValDef(Modifiers(Flag.MUTABLE), resultName, TypeTree(resultType), rhs)
-  }
-  
-  def mkHandlerCase(num: Int, rhs: c.Tree): CaseDef =
-    CaseDef(
-      // pattern
-      Bind(newTermName("any"), Typed(Ident(nme.WILDCARD), Ident(definitions.IntClass))),
-      // guard
-      Apply(Select(Ident(newTermName("any")), newTermName("$eq$eq")), List(Literal(Constant(num)))),
-      rhs
-    )
-  
-  def mkHandlerTreeFor(cases: List[(CaseDef, Int)]): c.Tree = {
-    val partFunIdent = Ident(c.mirror.staticClass("scala.PartialFunction"))
-    val intIdent = Ident(definitions.IntClass)
-    val unitIdent = Ident(definitions.UnitClass)
-    
-    val caseCheck =
-      Apply(Select(Apply(Select(Ident(newTermName("List")), newTermName("apply")),
-      cases.map(p => Literal(Constant(p._2)))), newTermName("contains")), List(Ident(newTermName("x$1"))))
-    
-    Block(List(
-      // anonymous subclass of PartialFunction[Int, Unit]
-      ClassDef(Modifiers(FINAL), newTypeName("$anon"), List(), Template(List(AppliedTypeTree(partFunIdent, List(intIdent, unitIdent))),
-        emptyValDef, List(
-          DefDef(Modifiers(), nme.CONSTRUCTOR, List(), List(List()), TypeTree(),
-            Block(List(Apply(Select(Super(This(tpnme.EMPTY), tpnme.EMPTY), nme.CONSTRUCTOR), List())), Literal(Constant(())))),
-          
-          DefDef(Modifiers(), newTermName("isDefinedAt"), List(), List(List(ValDef(Modifiers(PARAM), newTermName("x$1"), intIdent, EmptyTree))), TypeTree(),
-              caseCheck),
-          
-          DefDef(Modifiers(), newTermName("apply"), List(), List(List(ValDef(Modifiers(PARAM), newTermName("x$1"), intIdent, EmptyTree))), TypeTree(),
-            Match(Ident(newTermName("x$1")), cases.map(_._1)) // combine all cases into a single match
-          )
-        ))
-      )),
-      Apply(Select(New(Ident(newTypeName("$anon"))), nme.CONSTRUCTOR), List())
-    )
-  }
-  
-  def mkHandlerTree(num: Int, rhs: c.Tree): c.Tree =
-    mkHandlerTreeFor(List(mkHandlerCase(num, rhs) -> num))
-  
-  class AsyncState(stats: List[c.Tree], val state: Int, val nextState: Int) {
-    val body: c.Tree =
-      if (stats.size == 1) stats.head
-      else Block(stats: _*)
-    
-    val varDefs: List[(c.universe.TermName, c.universe.Type)] = List()
-    
-    def mkHandlerCaseForState(): CaseDef =
-      mkHandlerCase(state, Block((stats :+ mkStateTree(nextState) :+ Apply(Ident("resume"), List())): _*))
-    
-    def mkHandlerTreeForState(): c.Tree =
-      mkHandlerTree(state, Block((stats :+ mkStateTree(nextState) :+ Apply(Ident("resume"), List())): _*))
-    
-    def mkHandlerTreeForState(nextState: Int): c.Tree =
-      mkHandlerTree(state, Block((stats :+ mkStateTree(nextState) :+ Apply(Ident("resume"), List())): _*))
-    
-    def varDefForResult: Option[c.Tree] =
-      None
-    
-    def allVarDefs: List[c.Tree] =
-      varDefForResult.toList ++ varDefs.map(p => mkVarDefTree(p._2, p._1))
-    
-    override val toString: String =
-      s"AsyncState #$state, next = $nextState"
-  }
-  
-  class AsyncStateWithIf(stats: List[c.Tree], state: Int)
-      extends AsyncState(stats, state, 0) { // nextState unused, since encoded in then and else branches
-    
-    override def mkHandlerTreeForState(): c.Tree =
-      mkHandlerTree(state, Block(stats: _*))
-    
-    //TODO mkHandlerTreeForState(nextState: Int)
-    
-    override def mkHandlerCaseForState(): CaseDef =
-      mkHandlerCase(state, Block(stats: _*))
-    
-    override val toString: String =
-      s"AsyncStateWithIf #$state, next = $nextState"
-  }
-  
-  abstract class AsyncStateWithAwait(stats: List[c.Tree], state: Int, nextState: Int)
-      extends AsyncState(stats, state, nextState) {
-    val awaitable: c.Tree
-    val resultName: c.universe.TermName
-    val resultType: c.universe.Type
-    
-    override val toString: String =
-      s"AsyncStateWithAwait #$state, next = $nextState"
-    
-    /* Make an `onComplete` invocation:
-     * 
-     *     awaitable.onComplete {
-     *       case tr =>
-     *         resultName = tr.get
-     *         resume()
-     *     }
-     */
-    def mkOnCompleteTree: c.Tree = {
-      val assignTree =
-        Assign(
-          Ident(resultName.toString),
-          Select(Ident("tr"), c.universe.newTermName("get"))
-        )
-      val handlerTree =
-        Match(
-          EmptyTree,
-          List(
-            CaseDef(Bind(c.universe.newTermName("tr"), Ident("_")), EmptyTree,
-              Block(assignTree, Apply(Ident("resume"), List())) // rhs of case
-            )
-          )
-        )
-      Apply(
-        Select(awaitable, c.universe.newTermName("onComplete")),
-        List(handlerTree)
-      )
-    }
-    
-    /* Make an `onComplete` invocation which increments the state upon resuming:
-     * 
-     *     awaitable.onComplete {
-     *       case tr =>
-     *         resultName = tr.get
-     *         state += 1
-     *         resume()
-     *     }
-     */
-    def mkOnCompleteIncrStateTree: c.Tree = {
-      val tryGetTree =
-        Assign(
-          Ident(resultName.toString),
-          Select(Ident("tr"), c.universe.newTermName("get"))
-        )
-      val handlerTree =
-        Match(
-          EmptyTree,
-          List(
-            CaseDef(Bind(c.universe.newTermName("tr"), Ident("_")), EmptyTree,
-              Block(tryGetTree, mkIncrStateTree(), Apply(Ident("resume"), List())) // rhs of case
-            )
-          )
-        )
-      Apply(
-        Select(awaitable, c.universe.newTermName("onComplete")),
-        List(handlerTree)
-      )
-    }
-
-    /* Make an `onComplete` invocation which sets the state to `nextState` upon resuming:
-     * 
-     *     awaitable.onComplete {
-     *       case tr =>
-     *         resultName = tr.get
-     *         state = `nextState`
-     *         resume()
-     *     }
-     */
-    def mkOnCompleteStateTree(nextState: Int): c.Tree = {
-      val tryGetTree =
-        Assign(
-          Ident(resultName.toString),
-          Select(Ident("tr"), c.universe.newTermName("get"))
-        )
-      val handlerTree =
-        Match(
-          EmptyTree,
-          List(
-            CaseDef(Bind(c.universe.newTermName("tr"), Ident("_")), EmptyTree,
-              Block(tryGetTree, mkStateTree(nextState), Apply(Ident("resume"), List())) // rhs of case
-            )
-          )
-        )
-      Apply(
-        Select(awaitable, c.universe.newTermName("onComplete")),
-        List(handlerTree)
-      )
-    }
-
-    /* Make a partial function literal handling case #num:
-     * 
-     *     {
-     *       case any if any == num =>
-     *         stats
-     *         awaitable.onComplete {
-     *           case tr =>
-     *             resultName = tr.get
-     *             resume()
-     *         }
-     *     }
-     */
-    def mkHandlerForState(num: Int): c.Expr[PartialFunction[Int, Unit]] = {
-      assert(awaitable != null)
-      builder.mkHandler(num, c.Expr[Unit](Block((stats :+ mkOnCompleteTree): _*)))
-    }
-    
-    /* Make a partial function literal handling case #num:
-     * 
-     *     {
-     *       case any if any == num =>
-     *         stats
-     *         awaitable.onComplete {
-     *           case tr =>
-     *             resultName = tr.get
-     *             state += 1
-     *             resume()
-     *         }
-     *     }
-     */
-    override def mkHandlerTreeForState(): c.Tree = {
-      assert(awaitable != null)
-      mkHandlerTree(state, Block((stats :+ mkOnCompleteIncrStateTree): _*))
-    }
-    
-    override def mkHandlerTreeForState(nextState: Int): c.Tree = {
-      assert(awaitable != null)
-      mkHandlerTree(state, Block((stats :+ mkOnCompleteStateTree(nextState)): _*))
-    }
-    
-    override def mkHandlerCaseForState(): CaseDef = {
-      assert(awaitable != null)
-      mkHandlerCase(state, Block((stats :+ mkOnCompleteIncrStateTree): _*))
-    }
-    
-    override def varDefForResult: Option[c.Tree] = {
-      val rhs =
-        if (resultType <:< definitions.IntTpe) Literal(Constant(0))
-        else if (resultType <:< definitions.LongTpe) Literal(Constant(0L))
-        else if (resultType <:< definitions.BooleanTpe) Literal(Constant(false))
-        else if (resultType <:< definitions.FloatTpe) Literal(Constant(0.0f))
-        else if (resultType <:< definitions.DoubleTpe) Literal(Constant(0.0d))
-        else if (resultType <:< definitions.CharTpe) Literal(Constant(0.toChar))
-        else if (resultType <:< definitions.ShortTpe) Literal(Constant(0.toShort))
-        else if (resultType <:< definitions.ByteTpe) Literal(Constant(0.toByte))
-        else Literal(Constant(null))
-      Some(
-        ValDef(Modifiers(Flag.MUTABLE), resultName, TypeTree(resultType), rhs)
-      )
-    }
-  }
-  
-  /*
-   * Builder for a single state of an async method.
-   */
-  class AsyncStateBuilder(state: Int, private var nameMap: Map[c.Symbol, c.Name]) extends Builder[c.Tree, AsyncState] {
-    self =>
-    
-    /* Statements preceding an await call. */
-    private val stats = ListBuffer[c.Tree]()
-    
-    /* Argument of an await call. */
-    var awaitable: c.Tree = null
-    
-    /* Result name of an await call. */
-    var resultName: c.universe.TermName = null
-    
-    /* Result type of an await call. */
-    var resultType: c.universe.Type = null
-    
-    var nextState: Int = state + 1
-    
-    private val varDefs = ListBuffer[(c.universe.TermName, c.universe.Type)]()
-    
-    private val renamer = new Transformer {
-      override def transform(tree: Tree) = tree match {
-        case Ident(_) if nameMap.keySet contains tree.symbol =>
-          Ident(nameMap(tree.symbol))
-        case _ =>
-          super.transform(tree)
-      }
-    }
-    
-    def += (stat: c.Tree): this.type = {
-      stats += c.resetAllAttrs(renamer.transform(stat).duplicate)
-      this
-    }
-    
-    //TODO do not ignore `mods`
-    def addVarDef(mods: Any, name: c.universe.TermName, tpt: c.Tree, rhs: c.Tree, extNameMap: Map[c.Symbol, c.Name]): this.type = {
-      varDefs += (name -> tpt.tpe)
-      nameMap ++= extNameMap // update name map
-      this += Assign(Ident(name), c.resetAllAttrs(renamer.transform(rhs).duplicate))
-      this
-    }
-    
-    def result(): AsyncState =
-      if (awaitable == null)
-        new AsyncState(stats.toList, state, nextState) {
-          override val varDefs = self.varDefs.toList
-        }
-      else
-        new AsyncStateWithAwait(stats.toList, state, nextState) {
-          val awaitable = self.awaitable
-          val resultName = self.resultName
-          val resultType = self.resultType
-          override val varDefs = self.varDefs.toList
-        }
-    
-    def clear(): Unit = {
-      stats.clear()
-      awaitable = null
-      resultName = null
-      resultType = null
-    }
-    
-    /* Result needs to be created as a var at the beginning of the transformed method body, so that
-     * it is visible in subsequent states of the state machine.
-     *
-     * @param awaitArg         the argument of await
-     * @param awaitResultName  the name of the variable that the result of await is assigned to
-     * @param awaitResultType  the type of the result of await
-     */
-    def complete(awaitArg: c.Tree, awaitResultName: c.universe.TermName, awaitResultType: Tree, extNameMap: Map[c.Symbol, c.Name], nextState: Int = state + 1): this.type = {
-      nameMap ++= extNameMap
-      awaitable = c.resetAllAttrs(renamer.transform(awaitArg).duplicate)
-      resultName = awaitResultName
-      resultType = awaitResultType.tpe
-      this.nextState = nextState
-      this
-    }
-    
-    def complete(nextState: Int): this.type = {
-      this.nextState = nextState
-      this
-    }
-    
-    def resultWithIf(condTree: c.Tree, thenState: Int, elseState: Int): AsyncState = {
-      // 1. build changed if-else tree
-      // 2. insert that tree at the end of the current state
-      val cond = c.resetAllAttrs(condTree.duplicate)
-      this += If(cond,
-          Block(mkStateTree(thenState), Apply(Ident("resume"), List())),
-          Block(mkStateTree(elseState), Apply(Ident("resume"), List())))
-      new AsyncStateWithIf(stats.toList, state) {
-        override val varDefs = self.varDefs.toList
-      }
-    }
-    
-    override def toString: String = {
-      val statsBeforeAwait = stats.mkString("\n")
-      s"ASYNC STATE:\n$statsBeforeAwait \nawaitable: $awaitable \nresult name: $resultName"
-    }
-  }
-
-  class AsyncBlockBuilder(stats: List[c.Tree], expr: c.Tree, startState: Int, endState: Int, budget: Int, private var toRename: Map[c.Symbol, c.Name]) {
-    val asyncStates = ListBuffer[builder.AsyncState]()
-    
-    private var stateBuilder = new builder.AsyncStateBuilder(startState, toRename) // current state builder
-    private var currState = startState
-    
-    private var remainingBudget = budget
-    
-    /* Fall back to CPS plug-in if tree contains an `await` call. */
-    def checkForUnsupportedAwait(tree: c.Tree) = if (tree exists {
-      case Apply(fun, _) if fun.symbol == awaitMethod => true
-      case _ => false
-    }) throw new FallbackToCpsException
-    
-    // populate asyncStates
-    for (stat <- stats) stat match {
-      // the val name = await(..) pattern
-      case ValDef(mods, name, tpt, Apply(fun, args)) if fun.symbol == awaitMethod =>
-        val newName = newTermName(Async.freshString(name.toString()))
-        toRename += (stat.symbol -> newName)
-        
-        asyncStates += stateBuilder.complete(args(0), newName, tpt, toRename).result // complete with await
-        if (remainingBudget > 0)
-          remainingBudget -= 1
-        else
-          assert(false, "too many invocations of `await` in current method")
-        currState += 1
-        stateBuilder = new builder.AsyncStateBuilder(currState, toRename)
-        
-      case ValDef(mods, name, tpt, rhs) =>
-        checkForUnsupportedAwait(rhs)
-        
-        val newName = newTermName(Async.freshString(name.toString()))
-        toRename += (stat.symbol -> newName)
-        // when adding assignment need to take `toRename` into account
-        stateBuilder.addVarDef(mods, newName, tpt, rhs, toRename)
-        
-      case If(cond, thenp, elsep) =>
-        checkForUnsupportedAwait(cond)
-        
-        val ifBudget: Int = remainingBudget / 2
-        remainingBudget -= ifBudget //TODO test if budget > 0
-        // state that we continue with after if-else: currState + ifBudget
-        
-        val thenBudget: Int = ifBudget / 2
-        val elseBudget = ifBudget - thenBudget
-        
-        asyncStates +=
-          // the two Int arguments are the start state of the then branch and the else branch, respectively
-          stateBuilder.resultWithIf(cond, currState + 1, currState + thenBudget)
-        
-        val thenBuilder = thenp match {
-          case Block(thenStats, thenExpr) =>
-            new AsyncBlockBuilder(thenStats, thenExpr, currState + 1, currState + ifBudget, thenBudget, toRename)
-          case _ =>
-            new AsyncBlockBuilder(List(thenp), Literal(Constant(())), currState + 1, currState + ifBudget, thenBudget, toRename)
-        }
-        asyncStates ++= thenBuilder.asyncStates
-        toRename ++= thenBuilder.toRename
-        
-        val elseBuilder = elsep match {
-          case Block(elseStats, elseExpr) =>
-            new AsyncBlockBuilder(elseStats, elseExpr, currState + thenBudget, currState + ifBudget, elseBudget, toRename)
-          case _ =>
-            new AsyncBlockBuilder(List(elsep), Literal(Constant(())), currState + thenBudget, currState + ifBudget, elseBudget, toRename)
-        }
-        asyncStates ++= elseBuilder.asyncStates
-        toRename ++= elseBuilder.toRename
-        
-        // create new state builder for state `currState + ifBudget`
-        currState = currState + ifBudget
-        stateBuilder = new builder.AsyncStateBuilder(currState, toRename)
-        
-      case _ =>
-        checkForUnsupportedAwait(stat)
-        stateBuilder += stat
-    }
-    // complete last state builder (representing the expressions after the last await)
-    stateBuilder += expr
-    val lastState = stateBuilder.complete(endState).result
-    asyncStates += lastState
-    
-    def mkCombinedHandlerExpr(): c.Expr[PartialFunction[Int, Unit]] = {
-      assert(asyncStates.size > 1)
-      
-      val cases = for (state <- asyncStates.toList) yield state.mkHandlerCaseForState()
-      c.Expr(mkHandlerTreeFor(cases zip asyncStates.init.map(_.state))).asInstanceOf[c.Expr[PartialFunction[Int, Unit]]]
-    }
-    
-    /* Builds the handler expression for a sequence of async states.
-     */
-    def mkHandlerExpr(): c.Expr[PartialFunction[Int, Unit]] = {
-      assert(asyncStates.size > 1)
-      
-      var handlerExpr =
-        c.Expr(asyncStates(0).mkHandlerTreeForState()).asInstanceOf[c.Expr[PartialFunction[Int, Unit]]]
-      
-      if (asyncStates.size == 2)
-        handlerExpr
-      else {
-        for (asyncState <- asyncStates.tail.init) { // do not traverse first or last state
-          val handlerTreeForNextState = asyncState.mkHandlerTreeForState()
-          val currentHandlerTreeNaked = c.resetAllAttrs(handlerExpr.tree.duplicate)
-          handlerExpr = c.Expr(
-            Apply(Select(currentHandlerTreeNaked, newTermName("orElse")),
-                  List(handlerTreeForNextState))).asInstanceOf[c.Expr[PartialFunction[Int, Unit]]]
-        }
-        handlerExpr
-      }
-    }
-
-  }
-}