diff options
Diffstat (limited to 'compiler')
-rw-r--r-- | compiler/src/dotty/tools/dotc/ast/Trees.scala | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/compiler/src/dotty/tools/dotc/ast/Trees.scala b/compiler/src/dotty/tools/dotc/ast/Trees.scala index 27be8c9d6..669e5429c 100644 --- a/compiler/src/dotty/tools/dotc/ast/Trees.scala +++ b/compiler/src/dotty/tools/dotc/ast/Trees.scala @@ -712,8 +712,11 @@ object Trees { 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.map(_.withPos(pos)) - new Thicket[T](newTrees).asInstanceOf[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 = |