Represent untyped operators as Ident instead of Name

This has two advantages:
- We can distinguish BackquotedIdent from Ident, allowing the user to
  use a defined "type `&`", see testcase.
- We get better positions for the operators. This is useful in IDEs, for
  example to get the type at point.

1 files changed, 5 insertions, 0 deletions

diff --git a/compiler/src/dotty/tools/dotc/ast/Trees.scala b/compiler/src/dotty/tools/dotc/ast/Trees.scala
index 6dc2c9a13..7ab8de39f 100644
--- a/compiler/src/dotty/tools/dotc/ast/Trees.scala
+++ b/compiler/src/dotty/tools/dotc/ast/Trees.scala
@@ -334,10 +334,15 @@ object Trees {
     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)"
   }